feat(tui): add agent picker preview

Co-authored-by: Dax Raad <d@ironbay.co>

.opencode/skills/opencode-drive/SKILL.md

@@ -0,0 +1,254 @@
+---
+name: opencode-drive
+description: Use when an agent needs drive OpenCode via a script or interact with an isolated instance
+---
+
+# OpenCode Drive
+
+Use `opencode-drive` to launch an isolated OpenCode instance and control it via commands or a script.
+
+There are two modes. Always default to using a script unless specifically directed to be interactive (connect
+to an existing running instance, or start a new one, and make a few changes to the UI and read it, and iterate
+on changes).
+
+Scripts allow you to run a full walkthrough in one run. When the script is done opencode-drive exits,
+stops all processes, and cleans up all artifacts.
+
+# Prepare The Environment
+
+Use `init` when files must be added to the isolated home or project before OpenCode starts. It prints the artifact directory without launching OpenCode. A later `start` with the same name reuses it.
+
+```bash
+artifacts=$(opencode-drive init --name demo)
+cp -R ./fixtures/home/. "$artifacts/"
+cp -R ./fixtures/project/. "$artifacts/files/"
+opencode-drive start --name demo --dev ~/projects/opencode
+```
+
+The simulated project is under `$artifacts/files`. Running `start` without a prior `init` initializes the artifacts automatically.
+
+# Scripted usage
+
+You can write scripts that walk through entire flows, and gives you full access to controlling
+the backend too. See examples of the script API at the bottom of this file.
+
+After creating or editing a script, always typecheck it before running. Never skip this step:
+
+```bash
+opencode-drive check ./reproduce-stale-exploring-empty.ts
+```
+
+Run it by passing `--script` to start:
+
+```bash
+opencode-drive start --name auto-stop-reproduction --script ./reproduce-stale-exploring-empty.ts
+```
+
+It will output information about the run, including paths to log files which you can read
+to inspect what happened. If you need to dig into failures that aren't clear, read those log
+files. If the script is unsuccessful, automatically fix the script and run it again.
+
+Scripts use one typed definition object. `setup` runs before OpenCode starts,
+and `fs.writeFile` always writes inside the simulated project.
+
+You can read the full typed API here: https://raw.githubusercontent.com/jlongster/opencode-drive/refs/heads/main/src/script/types.ts
+
+```ts
+import { defineScript } from "opencode-drive"
+
+export default defineScript({
+  async setup({ fs, config }) {
+    config.autoupdate = false
+    await fs.writeFile("src/example.ts", "export const value = 1\n")
+  },
+
+  async run({ ui, llm }) {
+    await ui.submit("Open src/example.ts")
+    await llm.send(llm.text("The file exports `value`."))
+    await ui.waitFor("The file exports `value`.")
+  },
+})
+```
+
+`setup` receives the current OpenCode config object, which starts from the
+default drive config unless the prepared instance already has one. When a script
+needs custom config, mutate this `config` parameter instead of generating and
+writing a new config object from scratch, so the script keeps the default
+provider/model settings unless it intentionally changes them.
+
+Note that the simulated model is a GPT model type, and opencode uses the `patch` tool for working with files Do not use a `edit` or `write` tool to edit files.
+
+Use `launch: "manual"` when the script needs to launch the server and every TUI
+itself (this is extremely rare, do not use this unless explicitly asked). In this
+mode `ui` is typed as `null`; call `server.launch()` exactly
+once before launching clients. Each `clients.launch(name)` result provides the
+same UI methods as the automatic client. You can see an example of this API
+here: https://raw.githubusercontent.com/jlongster/opencode-drive/refs/heads/main/examples/multiple-clients.ts
+
+Use the exported `wait(milliseconds)` utility for an unconditional delay.
+
+`await llm.send(...)` waits for the next request and resolves after OpenCode
+acknowledges its complete response. `llm.queue(...)` declares responses in
+advance. Chunks may be built with `text`, `reasoning`, `toolCall`, `raw`,
+`finish`, and `disconnect`. A normal response receives `finish("stop")`
+automatically unless it yields or queues an explicit terminal event.
+
+`llm.text(text, { delay, chunkSize })` defaults to a 2 ms delay and a
+15-character target varied by plus or minus 5 per chunk.
+
+`llm.reasoning` accepts the same options, and `llm.pause(milliseconds)` adds a
+delay between any two outputs.
+
+Use `llm.serve` for an ongoing typed response generator:
+
+```ts
+llm.serve(async function* (request, index) {
+  yield llm.reasoning(`Handling request ${index + 1}`)
+  yield llm.text(`Received ${request.id}`)
+  yield llm.finish("stop")
+})
+```
+
+The backend connection, response cleanup, cancellation, and recording
+completion are automatic.
+
+You can see some example scripts here:
+
+- https://raw.githubusercontent.com/jlongster/opencode-drive/refs/heads/main/examples/simple.ts
+- https://raw.githubusercontent.com/jlongster/opencode-drive/refs/heads/main/examples/serve.ts
+
+## Prune
+
+- `prune` removes artifact directories. These are always cleaned up after running a script
+  successfully, but leftover on failed runs. Always call this if a script fails.
+
+```bash
+opencode-drive prune --name demo
+
+// --force cleans up all artifcat directories
+opencode-dirve prune --force
+```
+
+# Live interaction usage
+
+- Always give headless instances a unique `--name`. Visible instances may omit it.
+- A normal headless `start` detaches automatically and returns after the instance is ready.
+- Do not add `&`; the long-running owner already runs in the background.
+- Configure simulated model responses after startup when needed.
+- Send ordered UI commands with `send`.
+- Always stop the instance when finished.
+
+```bash
+opencode-drive start --name demo
+
+opencode-drive send --name demo \
+  --command.ui.type '{"text":"Explain this project"}' \
+  --command.ui.enter
+
+opencode-drive stop --name demo
+```
+
+## Send UI Commands
+
+- Every `send` opens a connection to the named instance, runs its commands in order, and exits.
+- Combine typing and Enter in one command when submitting a prompt.
+- JSON-valued commands require one JSON argument.
+- Multiple command flags execute from left to right.
+
+Commands:
+
+- `--command.ui.type <json>` types into the focused editor. Arguments: `text` string.
+- `--command.ui.press <json>` presses a key. Arguments: `key` string; optional `modifiers` object with boolean `ctrl`, `shift`, `meta`, `super`, or `hyper`.
+- `--command.ui.enter` presses Enter. Arguments: none.
+- `--command.ui.arrow <json>` presses an arrow key. Arguments: `direction` is `up`, `down`, `left`, or `right`.
+- `--command.ui.focus <json>` focuses an element. Arguments: `target` is the numeric element `num` returned by `ui.state`.
+- `--command.ui.click <json>` clicks an element. Arguments: numeric `target`, `x`, and `y`; use the element `num` returned by `ui.state` as `target`.
+- `--command.ui.state` prints focus and interactive element metadata as JSON. Arguments: none.
+- `--command.ui.matches <json>` prints whether literal, case-sensitive text appears on screen. Arguments: `text` string.
+
+```bash
+opencode-drive send --name demo \
+  --command.ui.type '{"text":"Find the relevant code and explain it"}' \
+  --command.ui.enter
+
+opencode-drive send --name demo \
+  --command.ui.press '{"key":"p","modifiers":{"ctrl":true}}'
+
+opencode-drive send --name demo \
+  --command.ui.arrow '{"direction":"down"}'
+
+opencode-drive send --name demo \
+  --command.ui.focus '{"target":12}'
+
+opencode-drive send --name demo \
+  --command.ui.click '{"target":12,"x":4,"y":1}'
+
+opencode-drive send --name demo \
+  --command.ui.matches '{"text":"OpenCode"}'
+```
+
+To read the UI state and see information about interactable elements, use the `ui.state` command:
+
+```bash
+opencode-drive send --name demo --command.ui.state
+```
+
+## Configure LLM Responses
+
+- `responses` controls what the LLM responds with
+- Only use this if you are wanting to reproduce an exact type of response
+- Defaults are `text,reasoning,diff,tool` with `write,apply_patch`.
+- Supported types are `text`, `reasoning`, `diff`, and `tool`.
+- `--tools` limits generated tool calls to names offered by OpenCode.
+
+```bash
+opencode-drive responses --name demo \
+  --types text,reasoning,diff,tool \
+  --tools write,apply_patch
+
+opencode-drive responses --name demo \
+  --types tool \
+  --tools read,glob,grep
+```
+
+## Inspect The UI
+
+- `ui.state` prints focus and interactive element metadata as JSON.
+- `ui.matches` checks for literal, case-sensitive screen text.
+- `screenshot` prints the generated image path.
+
+```bash
+opencode-drive screenshot --name demo
+```
+
+## Lifecycle
+
+- `stop` waits for recording export and owner cleanup before returning.
+
+```bash
+opencode-drive stop --name demo
+```
+
+# Record The UI
+
+- Start with `--record` to capture a headless instance from its first rendered frame.
+- `stop` finishes the recording, exports an MP4, and prints its path.
+
+```bash
+opencode-drive start --name demo --record
+
+opencode-drive send --name demo \
+  --command.ui.type '{"text":"Show me the current architecture"}' \
+  --command.ui.enter
+
+opencode-drive stop --name demo
+```
+
+# Artifacts dir
+
+- `dir` prints the artifact directory for the instance.
+
+```bash
+opencode-drive dir --name demo
+```
+

AGENTS.md

@@ -164,5 +164,5 @@ const table = sqliteTable("session", {
 - Keep delivery vocabulary explicit. Prompts steer by default and promote at the next safe step boundary while the current drain requires continuation. An explicit `queue` input remains pending until the Session would otherwise become idle; promote one queued input at that boundary, then reevaluate continuation before promoting another. Promoting any new user input resets the selected agent's step allowance; a batch of steers resets it once.
 - One step is one logical LLM call; its durable record covers only the model-visible span. Do not write "provider turn", and do not use bare "turn" for a single call: "turn" is reserved for the future assistant-turn unit containing all steps from prompt promotion until the session would go idle.
 - Keep EventV2 replay owner claims separate from clustered Session execution ownership.
-- Keep the Instructions algebra and built-ins in `src/instructions`; keep instruction producers with their observed domains, and keep Session History selection plus `InstructionCheckpoint` and `InstructionEntry` persistence Session-owned. `InstructionDiscovery` observes ambient global and upward-project instructions. The runner composes built-ins, discovery, guidance, and entries explicitly in `loadInstructions`; there is no instruction registry.
-- The durable `Instructions.Applied` record is what the model was last told, per instruction source. Reconciliation narrates drift through `session.instructions.updated` and never rewrites the baseline; only completed compaction rebaselines, while Session movement or committed revert resets the `InstructionCheckpoint`. Unavailable sources keep the model's prior belief, blocking only a Session's first instruction baseline.
+- Keep the Instructions algebra and built-ins in `src/instructions`; keep instruction producers with their observed domains, and keep Session History selection plus `InstructionState` and `InstructionEntry` persistence Session-owned. `InstructionDiscovery` observes ambient global and upward-project instructions. The runner composes built-ins, discovery, guidance, and entries explicitly in `loadInstructions`; there is no instruction registry.
+- `session.instructions.updated` stores only changed source keys and content hashes. Blob values live once in `instruction_blob`; `instruction_state` is a rebuildable fold cache, never primary state. Render initial instructions and chronological updates from values during request assembly. Completed compaction moves the instruction epoch; Session movement and committed revert clear it. Unavailable sources retain the last value and block only the initial complete delta.

CONTEXT.md

@@ -13,11 +13,11 @@ The opaque algebra of independently refreshable typed instruction sources that r
 _Avoid_: Model Context, System Context
 
 **Session History**:
-The projected chronological conversation selected for a **Step** after applying the active compaction and **InstructionCheckpoint** baseline cutoffs.
+The projected chronological conversation selected for a **Step** after applying the active compaction boundary and interleaving derived **Instruction Updates** from the current **Instruction Epoch**.
 _Avoid_: Session Context
 
 **Instruction Source**:
-One independently observed typed value within **Instructions**, represented by a stable namespaced key, JSON codec, loader, pure baseline/update renderers, and an optional removal renderer.
+One independently read typed value within **Instructions**, represented by a stable namespaced key, canonical JSON codec, pure first/changed renderers, and an optional removal renderer.
 _Avoid_: Prompt fragment
 
 **InstructionEntry**:
@@ -26,22 +26,25 @@ One API-managed, durable, per-Session instruction value. Its slash-free client k
 **InstructionDiscovery**:
 The Location-scoped service that observes ambient global and upward-project `AGENTS.md` files as one ordered aggregate **Instruction Source**.
 
-**InstructionCheckpoint**:
-The Session-owned durable instruction baseline, baseline sequence, and `Instructions.Applied` record used to prepare later Steps.
+**Instruction State**:
+The Session-owned projection cache of one instruction log fold: epoch start, values at that start, current values, and the last folded sequence. It is rebuilt from durable events and never authors model-visible facts.
 
 **Instruction Update**:
-A durable chronological System message published as `session.instructions.updated` that tells the model the newly effective state of one or more changed **Instruction Sources**.
-_Avoid_: System notification, raw text diff
+A durable `session.instructions.updated` value delta admitted at a **Safe Step Boundary**. Its model-visible System text is rendered from stored values at request assembly and is never persisted verbatim.
+_Avoid_: Correction, stored prose, raw text diff
 
-**Instruction Baseline**:
-The exact joined instruction text stored by **InstructionCheckpoint** and sent as immutable provider-cache prefix state until completed compaction rebaselines it or Session movement or committed revert resets it.
+**Initial Instructions**:
+The deterministic instruction text rendered from values at the current **Instruction Epoch** start and sent as provider-cache prefix state until completed compaction moves the epoch or Session movement or committed revert resets it.
 _Avoid_: Live system prompt
 
-**Applied Instructions**:
-The overwriteable model-hidden `Instructions.Applied` record in **InstructionCheckpoint**, containing what the model was last told per **Instruction Source**.
+**Instruction Epoch**:
+The span between completed compactions. Its start is the last `session.compaction.ended` sequence, or the initial complete instruction delta when no prior epoch exists.
+
+**Instruction Values**:
+The key-to-hash map produced by folding instruction deltas in durable sequence order. Hash bodies live once in the content-addressed instruction blob store.
 
 **Unavailable Instruction Source**:
-An expected temporary inability to observe an **Instruction Source** value; the runtime retains its prior effective state and emits no update, while an unavailable source blocks creation of the first complete **Instruction Baseline**.
+An expected temporary inability to read an **Instruction Source** value; the runtime retains its prior effective value and emits no update, while an unavailable source blocks the initial complete delta.
 
 **Safe Step Boundary**:
 The point during Step preparation, after prior tool settlement and before durable input promotion, where instruction changes may be admitted chronologically.
@@ -53,7 +56,7 @@ A durable user input accepted into the Session inbox but not yet included in **S
 The durable transition that removes an **Admitted Prompt** from pending input and appends its user message to **Session History**.
 
 **Step**:
-One logical LLM call spanning pre-flight instruction checkpoint preparation, input promotion, request build, and compaction check; the provider stream; and tool settlement.
+One logical LLM call spanning pre-flight instruction synchronization, input promotion, request build, and compaction check; the provider stream; and tool settlement.
 _Avoid_: provider turn, turn (unqualified)
 
 **Physical Attempt**:
@@ -108,18 +111,16 @@ _Avoid_: Response envelope
 ## Relationships
 
 - **Instructions** is an opaque carrier composed from zero or more **Instruction Sources**.
-- **Model Context** is broader than **Instructions**. For each **Step**, the runner assembles the selected agent or provider system text, the **Instruction Baseline**, **Session History**, available tools, and step-local additions into one model request.
-- **Session History** contains projected conversational messages and admitted **Instruction Updates**; the active **Instruction Baseline** remains separate provider-request state.
+- **Model Context** is broader than **Instructions**. For each **Step**, the runner assembles the selected agent or provider system text, **Initial Instructions**, **Session History**, available tools, and step-local additions into one model request.
+- **Session History** persists conversational messages. The runner derives model-facing **Instruction Update** messages from value deltas and interleaves them by durable sequence; **Initial Instructions** remain separate provider-request state.
 - The runner explicitly loads and combines instruction built-ins, **InstructionDiscovery**, selected-agent skill guidance, reference guidance, MCP guidance, and **InstructionEntry** values. There is no instruction registry.
 - `Instructions.combine(...)` preserves caller order and rejects duplicate stable namespaced source keys. The runner loads its producers concurrently, then combines them in its fixed declared order.
-- Each **Instruction Source** loader returns one coherent typed value or explicitly reports unavailability. `Instructions.make(...)` hides the value type so differently typed sources compose uniformly; its codec compares and stores the value, while pure renderers produce baseline, update, and optional removal text.
-- `Instructions.initialize(...)` observes composed **Instructions** once and produces a complete **Instruction Baseline** with **Applied Instructions**.
-- `Instructions.reconcile(...)` observes composed **Instructions** once and returns either unchanged or one combined chronological update. It never rewrites the baseline.
-- `Instructions.rebaseline(...)` renders a fresh baseline after completed compaction, recalling previously applied values for sources that are temporarily unavailable.
-- A changed **Instruction Source** may contribute text to one **Instruction Update** containing the newly effective state.
-- An **Instruction Update** persists the exact combined rendered text sent to the model through `session.instructions.updated`.
-- **Applied Instructions** advances atomically with the corresponding durable **Instruction Update**.
-- **Applied Instructions** stores one codec-encoded JSON value and, for removable sources, a pre-rendered removal message per stable **Instruction Source** key.
+- Each **Instruction Source** read returns one coherent typed value, explicit removal, or temporary unavailability. `Instructions.make(...)` hides the value type so differently typed sources compose uniformly; its canonical codec defines storage and hash equivalence, while pure renderers produce first, changed, and optional removal text.
+- `Instructions.read(...)` reads every composed source concurrently and exactly once at the boundary. `Instructions.diff(...)` compares encoded-value hashes with current **Instruction Values** and returns one delta plus new blob bodies.
+- `Instructions.renderInitial(...)` renders values at the **Instruction Epoch** start. `Instructions.renderUpdate(...)` renders one hydrated delta against the values immediately before it.
+- A changed **Instruction Source** contributes its hash to one **Instruction Update**; explicit removal contributes the `"removed"` sentinel.
+- An **Instruction Update** persists only its value delta. Rendered text is derived during request assembly and excluded from compaction summaries.
+- The instruction blob insert, durable delta, and **Instruction State** advance commit atomically.
 - Changes from multiple **Instruction Sources** admitted at one safe boundary combine into one **Instruction Update**.
 - Instruction changes are sampled and admitted lazily at a **Safe Step Boundary**, never pushed asynchronously when their source changes.
 - At a **Safe Step Boundary**, prior tool results are already settled; instruction preparation completes before newly admitted user input promotes.
@@ -130,28 +131,27 @@ _Avoid_: Response envelope
 - A **Session Drain** is process-local coordination rather than a durable domain entity. Durable recovery must reason from prompts, projected history, physical attempts, and tool state rather than inventing an enclosing execution identity.
 - An **Execution** contains one or more **Session Drains**; a **Session Drain** contains one reserved assistant-turn span at a time; that span contains **Steps**; and each **Step** contains one or more **Physical Attempts** plus any tool calls it requires.
 - A **Step** record covers only the model-visible span from first assistant output through tool settlement; pre-flight leaves no record, and one Step settles at most one record.
-- The first **Step** renders the latest complete **Instruction Baseline** and creates its **InstructionCheckpoint** without emitting a redundant **Instruction Update**; an unavailable initial source blocks the Step instead of persisting an incomplete baseline.
+- The first **Step** admits one complete delta and renders **Initial Instructions** without narrating that delta in history; an unavailable initial source blocks the Step instead of persisting incomplete values.
 - Instruction preparation precedes durable input promotion on every Step so an unavailable first baseline leaves pending input untouched and later updates enter history before newly promoted input.
-- Completed compaction rebaselines the **InstructionCheckpoint** from current **Instructions** and removes earlier **Instruction Updates** from active projected model history while preserving durable audit history.
-- A newly composed **Instruction Source** absent from **Applied Instructions** emits its baseline rendering once at the next **Safe Step Boundary**.
+- Completed compaction moves the **Instruction Epoch** to the exact `session.compaction.ended` sequence and copies current hashes to the epoch's initial values. Earlier updates leave active model history while durable deltas remain.
+- A newly composed **Instruction Source** absent from current **Instruction Values** emits its first rendering once at the next **Safe Step Boundary**.
 - **Unavailable Instruction Source** uses stale-while-revalidate semantics and is distinct from a successfully loaded absence, which may emit removal text.
 - **InstructionDiscovery** observes ambient instructions as one ordered aggregate **Instruction Source**.
 - Ambient discovery reads global and upward-project `AGENTS.md` files and honors `OPENCODE_DISABLE_PROJECT_CONFIG` for project files.
 - After a successful internal file or directory read, nearby `AGENTS.md` files toward the Location root are injected once per Session as durable synthetic instruction messages.
 - **InstructionEntry** stores API-managed per-Session JSON values. Each entry contributes one `api/<key>` **Instruction Source**, so adding, replacing, or removing an entry is reconciled at the next **Safe Step Boundary**.
 - Location-scoped instruction producers naturally re-resolve when a moved Session next runs in its destination Location.
-- Moving a Session resets its **InstructionCheckpoint**, so the destination must initialize a complete baseline before another prompt can promote. Committed revert also resets the checkpoint.
+- Moving a Session clears its **Instruction State**, so the destination must admit a complete delta before another prompt can promote. Committed revert does the same; replay derives both resets from their durable events.
 - Selected-agent available-skill guidance is an **Instruction Source** composed explicitly by the runner. It lists only names and descriptions permitted for that agent; skill bodies and locations are exposed only through the permission-checked `skill` tool.
 - The selected agent and model are sampled when a **Step** starts. Changes admitted after that boundary apply to the next Step and do not restart the current Step.
 - An agent switch that changes selected-agent guidance produces an **Instruction Update** while preserving the current baseline.
 - Local tool authorization and pending permission requests retain the effective agent of the **Step** that issued the call; a later agent switch cannot change that call's policy.
 - Instruction source changes never wake idle Sessions; the next naturally scheduled **Safe Step Boundary** loads and compares current values lazily.
 - Once admitted, an **Instruction Update** remains durable even if the following **Physical Attempt** fails and is replayed unchanged on retry.
-- **Instruction Updates** remain durable Session-message history; normal user-facing transcript surfaces may hide them.
+- **Instruction Updates** remain durable value history but are not `session_message` rows. Clients display changed keys rather than model-facing prose.
 - The date **Instruction Source** initially preserves host-local calendar-date behavior; a configured user timezone may replace that default later.
-- An **Instruction Baseline** is stored durably and reused verbatim across process restarts until rebaseline or reset.
-- An **Instruction Baseline** durably preserves the exact joined text used for its part of the active provider-cache prefix.
-- A model/provider switch preserves the current **InstructionCheckpoint** and chronological conversation history; the new selection applies to the next **Step**.
+- **Initial Instructions** are recomputed deterministically from durable values for every request; rendered bytes are not stored.
+- A model/provider switch preserves current **Instruction Values**, the **Instruction Epoch**, and chronological conversation history; the new selection applies to the next **Step**.
 - **Native Continuation Metadata** remains in durable history. Step projection includes it only for a successful exact originating provider/model match; failed Steps and incompatible models omit opaque metadata, while non-empty visible reasoning lowers to ordinary assistant text after a model switch. This conservative relation may widen only when recorded provider tests establish compatibility.
 - **Model Request Options** remain provider-semantic through Catalog resolution. The Session runner maps them into the LLM package's provider-option namespace; the selected protocol adapter alone owns provider wire encoding.
 - **Generation Controls**, protocol-semantic **Model Request Options**, and compatibility request body fields are separate Catalog domains. A shared ingestion adapter partitions legacy and models.dev AI-SDK-shaped options before routing.
@@ -195,7 +195,7 @@ _Avoid_: Response envelope
 - `sessions.message({ sessionID, messageID })` is a required resource lookup. An unknown Session fails with `SessionNotFoundError`; a known Session with an absent or differently owned message fails with `MessageNotFoundError` without disclosing cross-Session ownership. Absence is not represented as `undefined` across the public HTTP boundary.
 - `sessions.interrupt({ sessionID })` first verifies that the durable Session exists, failing with `SessionNotFoundError` otherwise. For a known Session, interruption is idempotent: idle, already-settled, or locally unowned execution is a no-op.
 - `sessions.active()` snapshots the current process's foreground Session drain registry as a record of Session IDs to `{ type: "running" }`. Missing IDs are inactive; background subagents and tasks do not make their parent Session active, and process restart clears the registry.
-- `sessions.context({ sessionID })` preserves the existing message-only operation. It returns projected **Session History**; it does not include or represent the complete **Model Context**, whose system text, **Instruction Baseline**, tools, and step-local additions remain separate.
+- `sessions.context({ sessionID })` preserves the existing message-only operation. It returns projected **Session History**; it does not include or represent the complete **Model Context**, whose agent system text, **Initial Instructions**, tools, and step-local additions remain separate.
 - **Open question**: Should a future, separately named operation expose complete **Model Context**, including the instruction baseline, applied instruction metadata, tools, and step-local additions?
 - `sessions.prompt(...)` exposes `resume?: boolean`. Omitting it preserves durable admission followed by an advisory execution wake; `resume: false` requests durable admit-only behavior.
 - The public operation remains `sessions.prompt(...)`; `SessionPending.admit` is the internal primitive, while the public `Admission` result and `resume` option express its durable admission semantics.

artifacts/glm52-rise-video/sst-env.d.ts

@@ -0,0 +1,10 @@
+/* This file is auto-generated by SST. Do not edit. */
+/* tslint:disable */
+/* eslint-disable */
+/* deno-fmt-ignore-file */
+/* biome-ignore-all lint: auto-generated */
+
+/// <reference path="../../sst-env.d.ts" />
+
+import "sst"
+export {}

infra/lake.ts

@@ -67,6 +67,10 @@ const athenaWorkgroup = new aws.athena.Workgroup("LakeAthenaWorkgroup", {
   configuration: {
     enforceWorkgroupConfiguration: true,
     publishCloudwatchMetricsEnabled: true,
+    // Athena bills $5/TB scanned; kill any query that would scan more than 2 TB
+    // so a regression cannot silently burn money. Stats sync full passes scan
+    // ~250 GB as of 2026-07.
+    bytesScannedCutoffPerQuery: 2 * 1024 ** 4,
     resultConfiguration: {
       outputLocation: $interpolate`s3://${athenaResultsBucket.bucket}/`,
     },

infra/stats.ts

@@ -185,7 +185,9 @@ export const statSync = new sst.aws.Service("StatsSyncService", {
   cluster: lakeCluster,
   architecture: "arm64",
   cpu: "0.25 vCPU",
-  memory: "0.5 GB",
+  // 0.5 GB caused an OOM crash loop: every restart immediately re-ran the 4 Athena
+  // stats queries (~$5/pass) every ~5 minutes instead of hourly.
+  memory: "2 GB",
   image: {
     context: ".",
     dockerfile: "packages/stats/server/Dockerfile",

packages/app/e2e/regression/review-open-file.spec.ts

@@ -74,6 +74,10 @@ test("opens and searches project files inline", async ({ page }) => {
         "opencode.global.dat:layout",
         JSON.stringify({ review: { diffStyle: "split", panelOpened: true } }),
       )
+      localStorage.setItem(
+        "opencode.global.dat:review-panel-v2",
+        JSON.stringify({ sidebarOpened: false, sidebarWidth: 240, expandMode: "collapse" }),
+      )
       localStorage.setItem(
         "opencode.window.browser.dat:tabs",
         JSON.stringify([{ type: "session", server, sessionId: sessionID }]),
@@ -86,13 +90,16 @@ test("opens and searches project files inline", async ({ page }) => {
   await expectSessionTitle(page, title)
 
   const panel = page.locator("#review-panel")
+  const sidebar = panel.locator('[data-slot="session-review-v2-sidebar"]')
   const contextButton = page.getByRole("button", { name: "View context usage" })
   await contextButton.click()
   await expect(panel.getByRole("tab", { name: "Context" })).toHaveAttribute("data-selected", "")
   await panel.getByRole("button", { name: "Open file" }).click()
   await expect(panel.getByRole("tab", { name: "Open file" })).toHaveAttribute("data-selected", "")
+  await expect(sidebar).toBeVisible()
   await contextButton.click()
   await expect(panel.getByRole("tab", { name: "Context" })).toHaveAttribute("data-selected", "")
+  await expect(sidebar).toHaveCount(0)
   await panel.getByRole("button", { name: "Open file" }).click()
   const filter = panel.getByRole("combobox", { name: "Filter files" })
   await expect(filter).toBeFocused()
@@ -102,9 +109,11 @@ test("opens and searches project files inline", async ({ page }) => {
   await panel.getByRole("button", { name: "README.md" }).click()
   await expect(panel.getByRole("tab", { name: "README.md" })).toHaveAttribute("data-selected", "")
   await expect(panel.getByText("contents:README.md", { exact: true })).toBeVisible()
+  await expect(sidebar).toHaveCount(0)
 
   await panel.getByRole("button", { name: "Open file" }).click()
   await expect(panel.getByRole("tab", { name: "README.md" })).toHaveCount(0)
+  await expect(sidebar).toBeVisible()
   await filter.fill("nested")
   const result = panel.getByRole("option", { name: /nested\.ts/ })
   await expect(result).toBeVisible()

packages/app/e2e/regression/session-timeline-shell-outline.spec.ts

@@ -0,0 +1,228 @@
+import { expect, test, type Locator, type Page } from "@playwright/test"
+import {
+  assistantMessage,
+  setupTimeline,
+  shell,
+  textPart,
+  toolPart,
+  userMessage,
+} from "../performance/timeline-stability/fixture"
+
+for (const deviceScaleFactor of [1.25, 1.5]) {
+  test(`keeps the shell outline inside a fractionally short virtual row at ${deviceScaleFactor}x`, async ({ page }) => {
+    const shellID = "prt_shell_outline"
+    const timeline = await setupTimeline(page, {
+      messages: [userMessage(), assistantMessage([shell(shellID, "completed", "shell output")])],
+      settings: { newLayoutDesigns: true, shellToolPartsExpanded: true },
+      reducedMotion: true,
+      deviceScaleFactor,
+    })
+    const part = page.locator(`[data-timeline-part-id="${shellID}"]`)
+    const output = part.locator('[data-component="bash-output"]')
+    const row = page.locator("[data-timeline-key]", { has: part })
+    await expect(output).toBeVisible()
+    await timeline.settle()
+
+    const geometry = await row.evaluate((element) => {
+      const output = element.querySelector<HTMLElement>('[data-component="bash-output"]')
+      if (!output) throw new Error("Shell output is unavailable")
+      const rowRect = element.getBoundingClientRect()
+      const outputRect = output.getBoundingClientRect()
+      // Match a rounded-down measurement at a fractional device-pixel phase.
+      element.style.height = `${outputRect.bottom - rowRect.top - 0.49}px`
+      element.style.transform = "translateY(0.25px)"
+      output.style.setProperty("--v2-border-border-base", "rgb(255, 0, 255)")
+      output.style.setProperty("background", "rgb(0, 0, 0)", "important")
+      const style = getComputedStyle(output)
+      return {
+        outputWidth: outputRect.width,
+        outputHeight: outputRect.height,
+        borderColor: style.borderTopColor,
+        boxShadow: style.boxShadow,
+        clipMargin: getComputedStyle(element).overflowClipMargin,
+      }
+    })
+    await timeline.settle()
+
+    const clipped = await row.evaluate((element) => {
+      const output = element.querySelector<HTMLElement>('[data-component="bash-output"]')!
+      return output.getBoundingClientRect().bottom - element.getBoundingClientRect().bottom
+    })
+    expect(clipped).toBeCloseTo(0.49, 1)
+
+    expect(await page.evaluate(() => devicePixelRatio)).toBe(deviceScaleFactor)
+    const edges = await captureCardEdges(page, output)
+
+    expect(edges.box.width).toBeCloseTo(geometry.outputWidth, 2)
+    expect(edges.box.height).toBeCloseTo(geometry.outputHeight, 2)
+    expect(geometry.borderColor).toBe("rgb(255, 0, 255)")
+    expect(geometry.boxShadow).toBe("none")
+    expect(geometry.clipMargin).toBe("0.5px")
+    expect(edges.magenta.top).toBeGreaterThan(0.75)
+    expect(edges.magenta.bottom).toBeGreaterThan(0.75)
+    expect(edges.magenta.vertical).toBeGreaterThanOrEqual(2)
+  })
+}
+
+test("keeps the patch card inside a fractionally short virtual row", async ({ page }) => {
+  const patchID = "prt_patch_outline"
+  const file = {
+    filePath: "src/outline.ts",
+    relativePath: "src/outline.ts",
+    type: "update",
+    additions: 1,
+    deletions: 1,
+    before: "const outline = false\n",
+    after: "const outline = true\n",
+  }
+  const timeline = await setupTimeline(page, {
+    messages: [
+      userMessage(),
+      assistantMessage([
+        toolPart(patchID, "apply_patch", "completed", { files: [file.filePath] }, { metadata: { files: [file] } }),
+      ]),
+    ],
+    settings: { editToolPartsExpanded: true, newLayoutDesigns: true },
+    reducedMotion: true,
+  })
+  const part = page.locator(`[data-timeline-part-id="${patchID}"]`)
+  const card = part.locator('[data-component="accordion"][data-scope="apply-patch"]')
+  const row = page.locator("[data-timeline-key]", { has: part })
+  await expect(card).toBeVisible()
+  await timeline.settle()
+
+  const geometry = await row.evaluate((element) => {
+    const card = element.querySelector<HTMLElement>('[data-component="accordion"][data-scope="apply-patch"]')
+    if (!card) throw new Error("Patch card is unavailable")
+    const rowRect = element.getBoundingClientRect()
+    const cardRect = card.getBoundingClientRect()
+    element.style.height = `${cardRect.bottom - rowRect.top - 0.49}px`
+    const clipMargin = getComputedStyle(element).overflowClipMargin
+    const bottom = element.getBoundingClientRect().bottom
+    return {
+      overflow: card.getBoundingClientRect().bottom - bottom,
+      paintOverflow: card.getBoundingClientRect().bottom - bottom - Number.parseFloat(clipMargin),
+      clipMargin,
+      cardWidth: cardRect.width,
+      cardHeight: cardRect.height,
+    }
+  })
+  await timeline.settle()
+
+  expect(geometry.overflow).toBeCloseTo(0.49, 1)
+  expect(geometry.paintOverflow).toBeLessThanOrEqual(0)
+  const edges = await captureCardEdges(page, card)
+  expect(edges.box.width).toBeCloseTo(geometry.cardWidth, 2)
+  expect(edges.box.height).toBeCloseTo(geometry.cardHeight, 2)
+  expect(edges.luminance.top).toBeLessThan(245)
+  expect(edges.luminance.bottom).toBeLessThan(245)
+  expect(Math.abs(edges.luminance.bottom - edges.luminance.top)).toBeLessThan(10)
+  expect(geometry.clipMargin).toBe("0.5px")
+})
+
+test("allows paint rounding for every framed row but not fixed turn gaps", async ({ page }) => {
+  const secondUserID = "msg_outline_second_user"
+  await setupTimeline(page, {
+    messages: [
+      userMessage(undefined, {
+        summary: {
+          diffs: [
+            {
+              file: "src/summary.ts",
+              additions: 1,
+              deletions: 1,
+              patch: "@@ -1 +1 @@\n-export const value = 1\n+export const value = 2",
+            },
+          ],
+        },
+      }),
+      assistantMessage([textPart("prt_outline_text", "Assistant text")]),
+      userMessage(undefined, { id: secondUserID, created: 1700000010000 }),
+      assistantMessage([], {
+        id: "msg_outline_second_assistant",
+        parentID: secondUserID,
+        created: 1700000011000,
+      }),
+    ],
+  })
+  await expect(page.locator('[data-timeline-row="DiffSummary"]')).toBeVisible()
+  await expect(page.locator('[data-timeline-row="TurnGap"]')).toBeVisible()
+
+  const rows = await page.locator("[data-timeline-key]").evaluateAll((elements) =>
+    elements.map((element) => ({
+      tag: element.querySelector<HTMLElement>("[data-timeline-row]")?.dataset.timelineRow,
+      clipMargin: getComputedStyle(element).overflowClipMargin,
+    })),
+  )
+  expect(rows.filter((row) => row.tag !== "TurnGap").every((row) => row.clipMargin === "0.5px")).toBe(true)
+  expect(rows.filter((row) => row.tag === "TurnGap")).toEqual([{ tag: "TurnGap", clipMargin: "0px" }])
+})
+
+async function captureCardEdges(page: Page, card: Locator) {
+  const box = await card.boundingBox()
+  if (!box) throw new Error("Tool card bounds are unavailable")
+  const viewport = page.viewportSize()
+  if (!viewport) throw new Error("Viewport bounds are unavailable")
+  const screenshot = await page.screenshot()
+  return page.evaluate(
+    async ({ source, box, viewport }) => {
+      const image = new Image()
+      image.src = source
+      await image.decode()
+      const canvas = document.createElement("canvas")
+      canvas.width = image.naturalWidth
+      canvas.height = image.naturalHeight
+      const context = canvas.getContext("2d")
+      if (!context) throw new Error("2D canvas is unavailable")
+      context.drawImage(image, 0, 0)
+      const scale = {
+        x: image.naturalWidth / viewport.width,
+        y: image.naturalHeight / viewport.height,
+      }
+      const rows = (candidates: number[]) => {
+        const left = Math.floor((box.x + 8) * scale.x)
+        const width = Math.floor((box.width - 16) * scale.x)
+        return candidates.map((row) => {
+          const pixels = context.getImageData(left, row, width, 1).data
+          const indexes = Array.from({ length: width }, (_, index) => index * 4)
+          return {
+            luminance:
+              indexes
+                .map((index) => (pixels[index]! + pixels[index + 1]! + pixels[index + 2]!) / 3)
+                .reduce((sum, value) => sum + value, 0) / width,
+            magenta:
+              indexes.filter((index) => pixels[index]! > 200 && pixels[index + 1]! < 180 && pixels[index + 2]! > 200)
+                .length / width,
+          }
+        })
+      }
+      const pixels = context.getImageData(0, 0, image.naturalWidth, image.naturalHeight).data
+      const columns = new Uint32Array(image.naturalWidth)
+      for (let index = 0; index < pixels.length; index += 4) {
+        if (pixels[index]! <= 200 || pixels[index + 1]! >= 180 || pixels[index + 2]! <= 200) continue
+        columns[(index / 4) % image.naturalWidth] = columns[(index / 4) % image.naturalWidth]! + 1
+      }
+      const top = box.y * scale.y
+      const bottom = (box.y + box.height) * scale.y
+      const topRows = rows([Math.floor(top) - 1, Math.floor(top), Math.ceil(top)])
+      const bottomRows = rows([Math.floor(bottom) - 2, Math.floor(bottom) - 1, Math.ceil(bottom) - 1])
+      return {
+        box,
+        luminance: {
+          top: Math.min(...topRows.map((row) => row.luminance)),
+          bottom: rows([Math.ceil(bottom) - 1])[0]!.luminance,
+        },
+        magenta: {
+          top: Math.max(...topRows.map((row) => row.magenta)),
+          bottom: Math.max(...bottomRows.map((row) => row.magenta)),
+          vertical: Array.from(columns).filter((count) => count > box.height * scale.y * 0.75).length,
+        },
+      }
+    },
+    {
+      source: `data:image/png;base64,${screenshot.toString("base64")}`,
+      viewport,
+      box,
+    },
+  )
+}

packages/app/src/components/prompt-input.tsx

@@ -36,6 +36,8 @@ import { Icon } from "@opencode-ai/ui/icon"
 import { ProviderIcon } from "@opencode-ai/ui/provider-icon"
 import { Tooltip, TooltipKeybind } from "@opencode-ai/ui/tooltip"
 import { ButtonV2 } from "@opencode-ai/ui/v2/button-v2"
+import { Icon as IconV2 } from "@opencode-ai/ui/v2/icon"
+import { IconButtonV2 } from "@opencode-ai/ui/v2/icon-button-v2"
 import { KeybindV2 } from "@opencode-ai/ui/v2/keybind-v2"
 import { MenuV2 } from "@opencode-ai/ui/v2/menu-v2"
 import { TooltipV2 } from "@opencode-ai/ui/v2/tooltip-v2"
@@ -1333,6 +1335,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
       onQueue: props.onQueue,
       onAbort: props.onAbort,
       onSubmit: props.onSubmit,
+      model: props.controls.model.selection,
     })
 
   const handleKeyDown = (event: KeyboardEvent) => {
@@ -1704,22 +1707,19 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
                   >
                     <MenuV2 gutter={6} modal={false} placement="top-start">
                       <MenuV2.Trigger
-                        as={IconButton}
+                        as={IconButtonV2}
                         data-action="prompt-attach"
                         type="button"
-                        icon="plus"
-                        variant="ghost"
-                        class="size-7 rounded-md p-[6px] text-v2-icon-icon-muted"
+                        icon={<IconV2 name="plus" />}
+                        variant="ghost-muted"
+                        size="large"
                         style={buttons()}
                         disabled={store.mode !== "normal"}
                         tabIndex={store.mode === "normal" ? undefined : -1}
                         aria-label={language.t("prompt.menu.addImagesAndFiles")}
                       />
                       <MenuV2.Portal>
-                        <MenuV2.Content
-                          class="[&_[data-slot=menu-v2-item-shortcut]]:w-5 [&_[data-slot=menu-v2-item-shortcut]]:justify-center"
-                          style={{ "min-width": "180px" }}
-                        >
+                        <MenuV2.Content style={{ "min-width": "180px" }}>
                           <MenuV2.Item onSelect={pick} shortcut={command.keybind("file.attach")}>
                             {language.t("prompt.menu.imagesAndFiles")}
                           </MenuV2.Item>

packages/app/src/components/prompt-input/submit.test.ts

@@ -1,5 +1,6 @@
 import { beforeAll, beforeEach, describe, expect, mock, test } from "bun:test"
 import type { Prompt } from "@/context/prompt"
+import type { ModelSelection } from "@/context/local"
 
 let createPromptSubmit: typeof import("./submit").createPromptSubmit
 
@@ -33,6 +34,10 @@ const prompt = {
   current: () => promptValue,
   cursor: () => 0,
   dirty: () => true,
+  model: {
+    current: () => undefined,
+    set: () => undefined,
+  },
   reset: () => undefined,
   set: () => undefined,
   context: {
@@ -378,6 +383,39 @@ describe("prompt submit worktree selection", () => {
     })
   })
 
+  test("uses an injected model selection", async () => {
+    params = { id: "session-1" }
+    const model = {
+      current: () => ({ id: "draft-model", provider: { id: "draft-provider" } }),
+      variant: { current: () => "draft-variant" },
+    } as unknown as ModelSelection
+    const submit = createPromptSubmit({
+      prompt,
+      info: () => ({ id: "session-1" }),
+      imageAttachments: () => [],
+      commentCount: () => 0,
+      autoAccept: () => false,
+      mode: () => "normal",
+      working: () => false,
+      editor: () => undefined,
+      queueScroll: () => undefined,
+      promptLength: (value) => value.reduce((sum, part) => sum + ("content" in part ? part.content.length : 0), 0),
+      addToHistory: () => undefined,
+      resetHistoryNavigation: () => undefined,
+      setMode: () => undefined,
+      setPopover: () => undefined,
+      model,
+    })
+
+    await submit.handleSubmit({ preventDefault: () => undefined } as unknown as Event)
+
+    expect(optimistic[0]).toMatchObject({
+      message: {
+        model: { providerID: "draft-provider", modelID: "draft-model", variant: "draft-variant" },
+      },
+    })
+  })
+
   test("seeds new sessions before optimistic prompts are added", async () => {
     const submit = createPromptSubmit({
       prompt,

packages/app/src/components/prompt-input/submit.ts

@@ -3,12 +3,12 @@ import { showToast } from "@/utils/toast"
 import { base64Encode } from "@opencode-ai/core/util/encode"
 import { Binary } from "@opencode-ai/core/util/binary"
 import { useNavigate, useParams, useSearchParams } from "@solidjs/router"
-import { batch, type Accessor } from "solid-js"
+import { batch, startTransition, type Accessor } from "solid-js"
 import { useTabs } from "@/context/tabs"
 import { useServerSync, type ServerSync } from "@/context/server-sync"
 import { useLanguage } from "@/context/language"
 import { useLayout } from "@/context/layout"
-import { useLocal } from "@/context/local"
+import { useLocal, type ModelSelection } from "@/context/local"
 import { usePermission } from "@/context/permission"
 import { type ContextItem, type ImageAttachmentPart, type Prompt, type usePrompt } from "@/context/prompt"
 import { useSDK, type DirectorySDK } from "@/context/sdk"
@@ -191,6 +191,7 @@ type PromptSubmitInput = {
   onQueue?: (draft: FollowupDraft) => void
   onAbort?: () => void
   onSubmit?: () => void
+  model?: ModelSelection
 }
 
 export function createPromptSubmit(input: PromptSubmitInput) {
@@ -296,9 +297,10 @@ export function createPromptSubmit(input: PromptSubmitInput) {
       return
     }
 
-    const currentModel = local.model.current()
+    const modelSelection = input.model ?? local.model
+    const currentModel = modelSelection.current()
     const currentAgent = local.agent.current()
-    const variant = local.model.variant.current()
+    const variant = modelSelection.variant.current()
     if (!currentModel || !currentAgent) {
       showToast({
         title: language.t("prompt.toast.modelAgentRequired.title"),
@@ -372,13 +374,20 @@ export function createPromptSubmit(input: PromptSubmitInput) {
       if (created) {
         seed(sessionDirectory, created)
         session = created
-        if (shouldAutoAccept) permission.enableAutoAccept(session.id, sessionDirectory)
-        local.session.promote(sessionDirectory, session.id)
-        layout.handoff.setTabs(base64Encode(sessionDirectory), session.id)
-        const draftID = search.draftId
-        if (draftID) tabs.promoteDraft(draftID, { server: tabs.draft(draftID).server, sessionId: session.id })
-        else navigate(`/${base64Encode(sessionDirectory)}/session/${session.id}`)
-        submission.retarget(prompt.capture({ dir: base64Encode(sessionDirectory), id: session.id }))
+        await startTransition(() => {
+          if (!session) return
+          if (shouldAutoAccept) permission.enableAutoAccept(session.id, sessionDirectory)
+          local.session.promote(sessionDirectory, session.id, {
+            agent: currentAgent.name,
+            model: { providerID: currentModel.provider.id, modelID: currentModel.id },
+            variant: variant ?? null,
+          })
+          layout.handoff.setTabs(base64Encode(sessionDirectory), session.id)
+          const draftID = search.draftId
+          if (draftID) tabs.promoteDraft(draftID, { server: tabs.draft(draftID).server, sessionId: session.id })
+          else navigate(`/${base64Encode(sessionDirectory)}/session/${session.id}`)
+          submission.retarget(prompt.capture({ dir: base64Encode(sessionDirectory), id: session.id }))
+        })
       }
     }
     if (!session) {

packages/app/src/components/session-context-usage.tsx

@@ -12,7 +12,7 @@ import { useSync } from "@/context/sync"
 import { useLanguage } from "@/context/language"
 import { useProviders } from "@/hooks/use-providers"
 import { useSDK } from "@/context/sdk"
-import { getSessionContext, getSessionTokenTotal } from "@/components/session/session-context-metrics"
+import { getSessionContext } from "@/components/session/session-context-metrics"
 import { useSessionLayout } from "@/pages/session/session-layout"
 import { createSessionTabs } from "@/pages/session/helpers"
 import { useSettings } from "@/context/settings"
@@ -74,7 +74,6 @@ export function SessionContextUsage(props: SessionContextUsageProps) {
   )
 
   const context = createMemo(() => getSessionContext(messages(), [...providers.all().values()]))
-  const tokens = createMemo(() => info()?.tokens)
   const cost = createMemo(() => {
     return usd().format(info()?.cost ?? 0)
   })
@@ -132,7 +131,7 @@ export function SessionContextUsage(props: SessionContextUsageProps) {
       <ContextTooltipRow name={language.t("context.usage.usage")} value={`${context()?.usage ?? 0}%`} />
       <ContextTooltipRow
         name={language.t("context.usage.tokens")}
-        value={getSessionTokenTotal(tokens())?.toLocaleString(language.intl()) ?? "0"}
+        value={context()?.total.toLocaleString(language.intl()) ?? "0"}
       />
     </div>
   )

packages/app/src/components/session/session-context-metrics.test.ts

@@ -1,6 +1,6 @@
 import { describe, expect, test } from "bun:test"
 import type { Message } from "@opencode-ai/sdk/v2/client"
-import { getSessionContext, getSessionTokenTotal } from "./session-context-metrics"
+import { getSessionContext } from "./session-context-metrics"
 
 const assistant = (
   id: string,
@@ -38,10 +38,10 @@ const user = (id: string) => {
 }
 
 describe("getSessionContext", () => {
-  test("computes usage from latest assistant with tokens", () => {
+  test("computes token totals and usage from latest assistant with tokens", () => {
     const messages = [
       user("u1"),
-      assistant("a1", { input: 0, output: 0, reasoning: 0, read: 0, write: 0 }, 0.5),
+      assistant("a1", { input: 600, output: 200, reasoning: 100, read: 50, write: 50 }, 0.5),
       assistant("a2", { input: 300, output: 100, reasoning: 50, read: 25, write: 25 }, 1.25),
     ]
     const providers = [
@@ -60,6 +60,8 @@ describe("getSessionContext", () => {
     const ctx = getSessionContext(messages, providers)
 
     expect(ctx?.message.id).toBe("a2")
+    expect(ctx?.total).toBe(500)
+    expect(ctx?.input).toBe(300)
     expect(ctx?.usage).toBe(50)
     expect(ctx?.providerLabel).toBe("OpenAI")
     expect(ctx?.modelLabel).toBe("GPT-4.1")
@@ -94,15 +96,4 @@ describe("getSessionContext", () => {
 
     expect(ctx).toBeUndefined()
   })
-
-  test("computes stored session token totals", () => {
-    expect(
-      getSessionTokenTotal({
-        input: 10,
-        output: 20,
-        reasoning: 30,
-        cache: { read: 40, write: 50 },
-      }),
-    ).toBe(150)
-  })
 })

packages/app/src/components/session/session-context-metrics.ts

@@ -1,4 +1,4 @@
-import type { AssistantMessage, Message, Session } from "@opencode-ai/sdk/v2/client"
+import type { AssistantMessage, Message } from "@opencode-ai/sdk/v2/client"
 
 type Provider = {
   id: string
@@ -21,6 +21,7 @@ type Context = {
   modelLabel: string
   limit: number | undefined
   input: number
+  total: number
   usage: number | null
 }
 
@@ -54,6 +55,7 @@ const build = (messages: Message[] = [], providers: Provider[] = []): Context |
     modelLabel: model?.name ?? message.modelID,
     limit,
     input: message.tokens.input,
+    total,
     usage: limit ? Math.round((total / limit) * 100) : null,
   }
 }
@@ -61,8 +63,3 @@ const build = (messages: Message[] = [], providers: Provider[] = []): Context |
 export function getSessionContext(messages: Message[] = [], providers: Provider[] = []) {
   return build(messages, providers)
 }
-
-export function getSessionTokenTotal(tokens: Session["tokens"] | undefined) {
-  if (!tokens) return undefined
-  return tokens.input + tokens.output + tokens.reasoning + tokens.cache.read + tokens.cache.write
-}

packages/app/src/components/session/session-context-tab.tsx

@@ -15,7 +15,7 @@ import { useLanguage } from "@/context/language"
 import { useProviders } from "@/hooks/use-providers"
 import { useSDK } from "@/context/sdk"
 import { useSessionLayout } from "@/pages/session/session-layout"
-import { getSessionContext, getSessionTokenTotal } from "./session-context-metrics"
+import { getSessionContext } from "./session-context-metrics"
 import { estimateSessionContextBreakdown, type SessionContextBreakdownKey } from "./session-context-breakdown"
 import { createSessionContextFormatter } from "./session-context-format"
 
@@ -135,7 +135,6 @@ export function SessionContextTab() {
   )
 
   const ctx = createMemo(() => getSessionContext(messages(), [...providers.all().values()]))
-  const tokens = createMemo(() => info()?.tokens)
   const formatter = createMemo(() => createSessionContextFormatter(language.intl()))
 
   const cost = createMemo(() => {
@@ -204,14 +203,15 @@ export function SessionContextTab() {
     { label: "context.stats.provider", value: providerLabel },
     { label: "context.stats.model", value: modelLabel },
     { label: "context.stats.limit", value: () => formatter().number(ctx()?.limit) },
-    { label: "context.stats.totalTokens", value: () => formatter().number(getSessionTokenTotal(tokens())) },
+    { label: "context.stats.totalTokens", value: () => formatter().number(ctx()?.total) },
     { label: "context.stats.usage", value: () => formatter().percent(ctx()?.usage) },
-    { label: "context.stats.inputTokens", value: () => formatter().number(tokens()?.input) },
-    { label: "context.stats.outputTokens", value: () => formatter().number(tokens()?.output) },
-    { label: "context.stats.reasoningTokens", value: () => formatter().number(tokens()?.reasoning) },
+    { label: "context.stats.inputTokens", value: () => formatter().number(ctx()?.input) },
+    { label: "context.stats.outputTokens", value: () => formatter().number(ctx()?.message.tokens.output) },
+    { label: "context.stats.reasoningTokens", value: () => formatter().number(ctx()?.message.tokens.reasoning) },
     {
       label: "context.stats.cacheTokens",
-      value: () => `${formatter().number(tokens()?.cache.read)} / ${formatter().number(tokens()?.cache.write)}`,
+      value: () =>
+        `${formatter().number(ctx()?.message.tokens.cache.read)} / ${formatter().number(ctx()?.message.tokens.cache.write)}`,
     },
     { label: "context.stats.userMessages", value: () => counts().user.toLocaleString(language.intl()) },
     { label: "context.stats.assistantMessages", value: () => counts().assistant.toLocaleString(language.intl()) },

packages/app/src/components/session/session-sortable-terminal-tab-v2.tsx

@@ -211,7 +211,17 @@ export function SortableTerminalTabV2(props: {
           <MenuV2.Context.Trigger class="relative" as="div">
             <Tabs.Trigger
               value={props.terminal.id}
-              onClick={focus}
+              onMouseDown={(e) => {
+                // Switch on mousedown to shave the press-release delay off tab switches.
+                if (e.button !== 0) return
+                if (store.editing) return
+                focus()
+              }}
+              onClick={(e) => {
+                // Mouse navigation already happened on mousedown; detail 0 means keyboard activation.
+                if (e.detail > 0) return
+                focus()
+              }}
               closeButton={
                 <IconButton
                   icon="close-small"

packages/app/src/components/settings-v2/settings-v2.css

@@ -20,6 +20,11 @@
   height: 100%;
   overflow-y: auto;
   scrollbar-width: none;
+  user-select: none;
+}
+
+.settings-v2-panel :is(input, textarea, [contenteditable="true"]) {
+  user-select: text;
 }
 
 .settings-v2-panel::-webkit-scrollbar {
@@ -181,6 +186,7 @@
   flex-direction: column;
   gap: 8px;
   padding: 4px 0 4px 4px;
+  user-select: none;
 }
 
 .settings-v2-nav-footer > span {

packages/app/src/components/terminal.tsx

@@ -1,7 +1,8 @@
 import { withAlpha } from "@opencode-ai/ui/theme/color"
 import { useTheme } from "@opencode-ai/ui/theme/context"
 import { resolveThemeVariant } from "@opencode-ai/ui/theme/resolve"
-import type { HexColor } from "@opencode-ai/ui/theme/types"
+import { resolveThemeVariantV2 } from "@opencode-ai/ui/theme/v2/resolve"
+import type { HexColor, ResolvedV2Theme } from "@opencode-ai/ui/theme/types"
 import { showToast } from "@/utils/toast"
 import type { FitAddon, Ghostty, Terminal as Term } from "ghostty-web"
 import { type ComponentProps, createEffect, createMemo, onCleanup, onMount, splitProps } from "solid-js"
@@ -68,6 +69,19 @@ const debugTerminal = (...values: unknown[]) => {
   console.debug("[terminal]", ...values)
 }
 
+const resolveV2Token = (tokens: ResolvedV2Theme, key: string) => {
+  let current = tokens[key]
+  for (let i = 0; i < 8 && current; i++) {
+    const match = /^var\(--([^)]+)\)$/.exec(current.trim())
+    if (!match) {
+      const hex = current.trim()
+      if (/^#[0-9a-fA-F]{8}$/.test(hex)) return hex.slice(0, 7)
+      return hex
+    }
+    current = tokens[match[1]]
+  }
+}
+
 const useTerminalUiBindings = (input: {
   container: HTMLDivElement
   term: Term
@@ -238,7 +252,10 @@ export const Terminal = (props: TerminalProps) => {
     if (!variant?.seeds && !variant?.palette) return fallback
     const resolved = resolveThemeVariant(variant, mode === "dark")
     const text = resolved["text-stronger"] ?? fallback.foreground
-    const background = resolved["background-stronger"] ?? fallback.background
+    const background = settings.general.newLayoutDesigns()
+      ? (resolveV2Token(resolveThemeVariantV2(variant, mode === "dark"), "v2-background-bg-base") ??
+        fallback.background)
+      : (resolved["background-stronger"] ?? fallback.background)
     const alpha = mode === "dark" ? 0.25 : 0.2
     const base = text.startsWith("#") ? (text as HexColor) : (fallback.foreground as HexColor)
     const selectionBackground = withAlpha(base, alpha)

packages/app/src/components/titlebar.tsx

@@ -25,6 +25,7 @@ import { readSessionTabsRemovedDetail, SESSION_TABS_REMOVED_EVENT } from "@/comp
 import { useGlobal } from "@/context/global"
 import { ServerConnection, useServer } from "@/context/server"
 import { tabKey, useTabs } from "@/context/tabs"
+import type { PromptSession } from "@/context/prompt"
 import "./titlebar.css"
 import { newTabTooltipKeybind } from "./command-tooltip-keybind"
 
@@ -324,13 +325,20 @@ export function Titlebar(props: { update?: TitlebarUpdate }) {
               const route = layout.route()
               const activeSession = session()
               if (route.type === "session" && activeSession) {
-                tabs.newDraft({ server: route.server ?? server.key, directory: activeSession.directory }, "")
+                const sessionTab = {
+                  type: "session" as const,
+                  server: route.server ?? server.key,
+                  sessionId: activeSession.id,
+                }
+                const model = tabs.stateValue<PromptSession>(sessionTab, "prompt")?.model.current()
+                tabs.newDraft({ server: sessionTab.server, directory: activeSession.directory }, "", model)
                 return
               }
 
               const activeTab = currentTab()
               if (activeTab?.type === "draft") {
-                tabs.newDraft({ server: activeTab.server, directory: activeTab.directory }, "")
+                const model = tabs.stateValue<PromptSession>(activeTab, "prompt")?.model.current()
+                tabs.newDraft({ server: activeTab.server, directory: activeTab.directory }, "", model)
                 return
               }
 

packages/app/src/context/local.tsx

@@ -67,7 +67,7 @@ export const { use: useLocal, provider: LocalProvider } = createSimpleContext({
     const list = createMemo(() => sync().data.agent.filter((item) => item.mode !== "subagent" && !item.hidden))
     const connected = createMemo(() => new Set(providers.connected().map((item) => item.id)))
 
-    const [saved, setSaved] = persisted(
+    const [saved, setSaved, , savedReady] = persisted(
       {
         ...Persist.serverWorkspace(serverSDK().scope, sdk().directory, "model-selection", ["model-selection.v1"]),
         migrate,
@@ -375,11 +375,12 @@ export const { use: useLocal, provider: LocalProvider } = createSimpleContext({
       model,
       agent,
       session: {
+        ready: savedReady,
         reset() {
           setStore({ draft: undefined, promoting: undefined })
         },
-        promote(dir: string, session: string) {
-          const next = clone(snapshot())
+        promote(dir: string, session: string, state?: State) {
+          const next = clone(state ?? snapshot())
           if (!next) return
           const key = handoffKey(serverSDK().scope, dir, session)
           handoff.set(key, next)
@@ -409,3 +410,5 @@ export const { use: useLocal, provider: LocalProvider } = createSimpleContext({
     return result
   },
 })
+
+export type ModelSelection = ReturnType<typeof useLocal>["model"]

packages/app/src/context/prompt-state.test.ts

@@ -0,0 +1,29 @@
+import { describe, expect, test } from "bun:test"
+import { createRoot } from "solid-js"
+import { createPromptState, DEFAULT_PROMPT } from "./prompt-state"
+
+describe("prompt state initialization", () => {
+  test("initializes prompt text, cursor, and model together", () => {
+    createRoot((dispose) => {
+      const model = { providerID: "anthropic", modelID: "claude", variant: "high" }
+      const prompt = createPromptState({ prompt: "hello", model })
+
+      expect(prompt.current()).toEqual([{ type: "text", content: "hello", start: 0, end: 5 }])
+      expect(prompt.cursor()).toBe(5)
+      expect(prompt.model.current()).toEqual(model)
+      expect(prompt.model.current()).not.toBe(model)
+      dispose()
+    })
+  })
+
+  test("uses the default prompt without initial values", () => {
+    createRoot((dispose) => {
+      const prompt = createPromptState()
+
+      expect(prompt.current()).toEqual(DEFAULT_PROMPT)
+      expect(prompt.cursor()).toBeUndefined()
+      expect(prompt.model.current()).toBeUndefined()
+      dispose()
+    })
+  })
+})

packages/app/src/context/prompt-state.ts

@@ -0,0 +1,265 @@
+import { checksum } from "@opencode-ai/core/util/encode"
+import type { FilePartSource } from "@opencode-ai/sdk/v2/client"
+import { batch, createMemo, type Accessor } from "solid-js"
+import { createStore, type SetStoreFunction } from "solid-js/store"
+import type { FileSelection } from "@/context/file"
+import { Persist, persisted } from "@/utils/persist"
+import type { ServerScope } from "@/utils/server-scope"
+
+interface PartBase {
+  content: string
+  start: number
+  end: number
+}
+
+export interface TextPart extends PartBase {
+  type: "text"
+}
+
+export interface FileAttachmentPart extends PartBase {
+  type: "file"
+  path: string
+  selection?: FileSelection
+  mime?: string
+  filename?: string
+  url?: string
+  source?: FilePartSource
+}
+
+export interface AgentPart extends PartBase {
+  type: "agent"
+  name: string
+}
+
+export interface ImageAttachmentPart {
+  type: "image"
+  id: string
+  filename: string
+  sourcePath?: string
+  mime: string
+  dataUrl: string
+}
+
+export type ContentPart = TextPart | FileAttachmentPart | AgentPart | ImageAttachmentPart
+export type Prompt = ContentPart[]
+
+export type PromptModel = {
+  providerID: string
+  modelID: string
+  variant?: string | null
+}
+
+export type FileContextItem = {
+  type: "file"
+  path: string
+  selection?: FileSelection
+  comment?: string
+  commentID?: string
+  commentOrigin?: "review" | "file"
+  preview?: string
+}
+
+export type ContextItem = FileContextItem
+export type PromptScope = { draftID: string } | { dir: string; id?: string }
+
+export const DEFAULT_PROMPT: Prompt = [{ type: "text", content: "", start: 0, end: 0 }]
+
+type PromptStore = {
+  prompt: Prompt
+  cursor?: number
+  model?: PromptModel
+  context: {
+    items: (ContextItem & { key: string })[]
+  }
+}
+
+type InitialPrompt = {
+  prompt?: string
+  model?: PromptModel
+}
+
+function isSelectionEqual(a?: FileSelection, b?: FileSelection) {
+  if (!a && !b) return true
+  if (!a || !b) return false
+  return (
+    a.startLine === b.startLine && a.startChar === b.startChar && a.endLine === b.endLine && a.endChar === b.endChar
+  )
+}
+
+function isPartEqual(partA: ContentPart, partB: ContentPart) {
+  switch (partA.type) {
+    case "text":
+      return partB.type === "text" && partA.content === partB.content
+    case "file":
+      return (
+        partB.type === "file" &&
+        partA.path === partB.path &&
+        partA.mime === partB.mime &&
+        partA.filename === partB.filename &&
+        isSelectionEqual(partA.selection, partB.selection)
+      )
+    case "agent":
+      return partB.type === "agent" && partA.name === partB.name
+    case "image":
+      return partB.type === "image" && partA.id === partB.id
+  }
+}
+
+export function isPromptEqual(promptA: Prompt, promptB: Prompt): boolean {
+  if (promptA.length !== promptB.length) return false
+  for (let i = 0; i < promptA.length; i++) {
+    if (!isPartEqual(promptA[i], promptB[i])) return false
+  }
+  return true
+}
+
+function cloneSelection(selection?: FileSelection) {
+  if (!selection) return undefined
+  return { ...selection }
+}
+
+function clonePart(part: ContentPart): ContentPart {
+  if (part.type === "text") return { ...part }
+  if (part.type === "image") return { ...part }
+  if (part.type === "agent") return { ...part }
+  return {
+    ...part,
+    selection: cloneSelection(part.selection),
+  }
+}
+
+function clonePrompt(prompt: Prompt): Prompt {
+  return prompt.map(clonePart)
+}
+
+function contextItemKey(item: ContextItem) {
+  if (item.type !== "file") return item.type
+  const start = item.selection?.startLine
+  const end = item.selection?.endLine
+  const key = `${item.type}:${item.path}:${start}:${end}`
+
+  if (item.commentID) return `${key}:c=${item.commentID}`
+  const comment = item.comment?.trim()
+  if (!comment) return key
+  const digest = checksum(comment) ?? comment
+  return `${key}:c=${digest.slice(0, 8)}`
+}
+
+function isCommentItem(item: ContextItem | (ContextItem & { key: string })) {
+  return item.type === "file" && !!item.comment?.trim()
+}
+
+function createPromptActions(setStore: SetStoreFunction<PromptStore>) {
+  return {
+    set(prompt: Prompt, cursorPosition?: number) {
+      const next = clonePrompt(prompt)
+      batch(() => {
+        setStore("prompt", next)
+        if (cursorPosition !== undefined) setStore("cursor", cursorPosition)
+      })
+    },
+    reset() {
+      batch(() => {
+        setStore("prompt", clonePrompt(DEFAULT_PROMPT))
+        setStore("cursor", 0)
+      })
+    },
+  }
+}
+
+function promptTarget(serverScope: ServerScope, scope: PromptScope) {
+  if ("draftID" in scope) return Persist.draft(scope.draftID, "prompt")
+  const legacy = `${scope.dir}/prompt${scope.id ? "/" + scope.id : ""}.v2`
+  return Persist.serverScoped(serverScope, scope.dir, scope.id, "prompt", [legacy])
+}
+
+function promptStore(initial?: InitialPrompt): PromptStore {
+  const text = initial?.prompt
+  return {
+    prompt:
+      text === undefined ? clonePrompt(DEFAULT_PROMPT) : [{ type: "text", content: text, start: 0, end: text.length }],
+    cursor: text === undefined ? undefined : text.length,
+    model: initial?.model ? { ...initial.model } : undefined,
+    context: {
+      items: [],
+    },
+  }
+}
+
+function createPromptStateValue(store: PromptStore, setStore: SetStoreFunction<PromptStore>) {
+  const actions = createPromptActions(setStore)
+  const value = {
+    current: () => store.prompt,
+    cursor: createMemo(() => store.cursor),
+    dirty: () => !isPromptEqual(store.prompt, DEFAULT_PROMPT),
+    model: {
+      current: () => store.model,
+      set: (model: PromptModel | undefined) => setStore("model", model),
+    },
+    context: {
+      items: createMemo(() => store.context.items),
+      add(item: ContextItem) {
+        const key = contextItemKey(item)
+        if (store.context.items.find((x) => x.key === key)) return
+        setStore("context", "items", (items) => [...items, { key, ...item }])
+      },
+      remove(key: string) {
+        setStore("context", "items", (items) => items.filter((x) => x.key !== key))
+      },
+      removeComment(path: string, commentID: string) {
+        setStore("context", "items", (items) =>
+          items.filter((item) => !(item.type === "file" && item.path === path && item.commentID === commentID)),
+        )
+      },
+      updateComment(path: string, commentID: string, next: Partial<FileContextItem> & { comment?: string }) {
+        setStore("context", "items", (items) =>
+          items.map((item) => {
+            if (item.type !== "file" || item.path !== path || item.commentID !== commentID) return item
+            const value = { ...item, ...next }
+            return { ...value, key: contextItemKey(value) }
+          }),
+        )
+      },
+      replaceComments(items: FileContextItem[]) {
+        setStore("context", "items", (current) => [
+          ...current.filter((item) => !isCommentItem(item)),
+          ...items.map((item) => ({ ...item, key: contextItemKey(item) })),
+        ])
+      },
+    },
+    set: actions.set,
+    reset: actions.reset,
+    capture: () => value,
+  }
+  return value
+}
+
+function createPersistedPrompt(target: ReturnType<typeof promptTarget>, initial?: InitialPrompt) {
+  const [store, setStore, _, ready] = persisted(target, createStore<PromptStore>(promptStore(initial)))
+  return { ready, ...createPromptStateValue(store, setStore) }
+}
+
+export function createPromptSession(serverScope: ServerScope, scope: PromptScope, initial?: InitialPrompt) {
+  return createPersistedPrompt(promptTarget(serverScope, scope), initial)
+}
+
+export function createDraftPromptSession(draftID: string, initial?: InitialPrompt) {
+  return createPersistedPrompt(Persist.draft(draftID, "prompt"), initial)
+}
+
+export type PromptSession = ReturnType<typeof createPromptSession>
+
+export function createPromptReady(session: Accessor<PromptSession>) {
+  return Object.defineProperty(() => session().ready(), "promise", {
+    get: () => session().ready.promise,
+  }) as (() => boolean) & { readonly promise: Promise<unknown> | undefined }
+}
+
+export function createPromptState(initial?: InitialPrompt) {
+  const [store, setStore] = createStore<PromptStore>(promptStore(initial))
+  const ready = Object.assign(() => true, { promise: Promise.resolve(true) })
+  return {
+    ready,
+    ...createPromptStateValue(store, setStore),
+  }
+}

packages/app/src/context/prompt.tsx

@@ -1,186 +1,49 @@
+import { base64Encode } from "@opencode-ai/core/util/encode"
 import { createSimpleContext } from "@opencode-ai/ui/context"
-import { base64Encode, checksum } from "@opencode-ai/core/util/encode"
 import { useParams, useSearchParams } from "@solidjs/router"
-import { batch, createMemo, createRoot, getOwner, onCleanup, type Accessor } from "solid-js"
-import { createStore, type SetStoreFunction } from "solid-js/store"
-import type { FileSelection } from "@/context/file"
-import { Persist, persisted } from "@/utils/persist"
+import { createMemo, createRoot, getOwner, onCleanup } from "solid-js"
+import { requireServerKey } from "@/utils/session-route"
+import { ServerConnection } from "./server"
 import { useServerSDK } from "./server-sdk"
-import type { ServerScope } from "@/utils/server-scope"
+import { useSettings } from "./settings"
 import { useSDK } from "./sdk"
 import { useTabs, type Tab } from "./tabs"
-import { ServerConnection } from "./server"
-import { requireServerKey } from "@/utils/session-route"
-import { useSettings } from "./settings"
-import type { FilePartSource } from "@opencode-ai/sdk/v2/client"
+import {
+  createPromptReady,
+  createPromptSession,
+  type ContextItem,
+  type FileContextItem,
+  type Prompt,
+  type PromptModel,
+  type PromptScope,
+  type PromptSession,
+} from "./prompt-state"
 
-interface PartBase {
-  content: string
-  start: number
-  end: number
-}
-
-export interface TextPart extends PartBase {
-  type: "text"
-}
-
-export interface FileAttachmentPart extends PartBase {
-  type: "file"
-  path: string
-  selection?: FileSelection
-  mime?: string
-  filename?: string
-  url?: string
-  source?: FilePartSource
-}
-
-export interface AgentPart extends PartBase {
-  type: "agent"
-  name: string
-}
-
-export interface ImageAttachmentPart {
-  type: "image"
-  id: string
-  filename: string
-  sourcePath?: string
-  mime: string
-  dataUrl: string
-}
-
-export type ContentPart = TextPart | FileAttachmentPart | AgentPart | ImageAttachmentPart
-export type Prompt = ContentPart[]
-
-export type FileContextItem = {
-  type: "file"
-  path: string
-  selection?: FileSelection
-  comment?: string
-  commentID?: string
-  commentOrigin?: "review" | "file"
-  preview?: string
-}
-
-export type ContextItem = FileContextItem
-
-export const DEFAULT_PROMPT: Prompt = [{ type: "text", content: "", start: 0, end: 0 }]
-
-function isSelectionEqual(a?: FileSelection, b?: FileSelection) {
-  if (!a && !b) return true
-  if (!a || !b) return false
-  return (
-    a.startLine === b.startLine && a.startChar === b.startChar && a.endLine === b.endLine && a.endChar === b.endChar
-  )
-}
-
-function isPartEqual(partA: ContentPart, partB: ContentPart) {
-  switch (partA.type) {
-    case "text":
-      return partB.type === "text" && partA.content === partB.content
-    case "file":
-      return (
-        partB.type === "file" &&
-        partA.path === partB.path &&
-        partA.mime === partB.mime &&
-        partA.filename === partB.filename &&
-        isSelectionEqual(partA.selection, partB.selection)
-      )
-    case "agent":
-      return partB.type === "agent" && partA.name === partB.name
-    case "image":
-      return partB.type === "image" && partA.id === partB.id
-  }
-}
-
-export function isPromptEqual(promptA: Prompt, promptB: Prompt): boolean {
-  if (promptA.length !== promptB.length) return false
-  for (let i = 0; i < promptA.length; i++) {
-    if (!isPartEqual(promptA[i], promptB[i])) return false
-  }
-  return true
-}
-
-function cloneSelection(selection?: FileSelection) {
-  if (!selection) return undefined
-  return { ...selection }
-}
-
-function clonePart(part: ContentPart): ContentPart {
-  if (part.type === "text") return { ...part }
-  if (part.type === "image") return { ...part }
-  if (part.type === "agent") return { ...part }
-  return {
-    ...part,
-    selection: cloneSelection(part.selection),
-  }
-}
-
-function clonePrompt(prompt: Prompt): Prompt {
-  return prompt.map(clonePart)
-}
-
-function contextItemKey(item: ContextItem) {
-  if (item.type !== "file") return item.type
-  const start = item.selection?.startLine
-  const end = item.selection?.endLine
-  const key = `${item.type}:${item.path}:${start}:${end}`
-
-  if (item.commentID) {
-    return `${key}:c=${item.commentID}`
-  }
-
-  const comment = item.comment?.trim()
-  if (!comment) return key
-  const digest = checksum(comment) ?? comment
-  return `${key}:c=${digest.slice(0, 8)}`
-}
-
-function isCommentItem(item: ContextItem | (ContextItem & { key: string })) {
-  return item.type === "file" && !!item.comment?.trim()
-}
-
-function createPromptActions(
-  setStore: SetStoreFunction<{
-    prompt: Prompt
-    cursor?: number
-    context: {
-      items: (ContextItem & { key: string })[]
-    }
-  }>,
-) {
-  return {
-    set(prompt: Prompt, cursorPosition?: number) {
-      const next = clonePrompt(prompt)
-      batch(() => {
-        setStore("prompt", next)
-        if (cursorPosition !== undefined) setStore("cursor", cursorPosition)
-      })
-    },
-    reset() {
-      batch(() => {
-        setStore("prompt", clonePrompt(DEFAULT_PROMPT))
-        setStore("cursor", 0)
-      })
-    },
-  }
-}
+export {
+  createPromptReady,
+  createPromptSession,
+  createPromptState,
+  DEFAULT_PROMPT,
+  isPromptEqual,
+} from "./prompt-state"
+export type {
+  AgentPart,
+  ContentPart,
+  ContextItem,
+  FileAttachmentPart,
+  FileContextItem,
+  ImageAttachmentPart,
+  Prompt,
+  PromptModel,
+  PromptScope,
+  PromptSession,
+  TextPart,
+} from "./prompt-state"
 
 const WORKSPACE_KEY = "__workspace__"
 const MAX_PROMPT_SESSIONS = 20
 
-type PromptSession = ReturnType<typeof createPromptSession>
-
-type PromptStore = {
-  prompt: Prompt
-  cursor?: number
-  context: {
-    items: (ContextItem & { key: string })[]
-  }
-}
-
-type Scope = { draftID: string } | { dir: string; id?: string }
-
-export function selectPromptTab(tabs: Tab[], scope: Scope, server: ServerConnection.Key) {
+export function selectPromptTab(tabs: Tab[], scope: PromptScope, server: ServerConnection.Key) {
   if ("draftID" in scope) return tabs.find((tab) => tab.type === "draft" && tab.draftID === scope.draftID)
   if (!scope.id) return
   return (
@@ -189,7 +52,7 @@ export function selectPromptTab(tabs: Tab[], scope: Scope, server: ServerConnect
   )
 }
 
-function scopeKey(scope: Scope) {
+function scopeKey(scope: PromptScope) {
   if ("draftID" in scope) return `draft:${scope.draftID}`
   return `${scope.dir}:${scope.id ?? WORKSPACE_KEY}`
 }
@@ -199,91 +62,6 @@ type PromptCacheEntry = {
   dispose: VoidFunction
 }
 
-function promptTarget(serverScope: ServerScope, scope: Scope) {
-  if ("draftID" in scope) return Persist.draft(scope.draftID, "prompt")
-  const legacy = `${scope.dir}/prompt${scope.id ? "/" + scope.id : ""}.v2`
-  return Persist.serverScoped(serverScope, scope.dir, scope.id, "prompt", [legacy])
-}
-
-export function createPromptSession(serverScope: ServerScope, scope: Scope) {
-  const [store, setStore, _, ready] = persisted(
-    promptTarget(serverScope, scope),
-    createStore<PromptStore>(promptStore()),
-  )
-
-  return { ready, ...createPromptStateValue(store, setStore) }
-}
-
-export function createPromptReady(session: Accessor<PromptSession>) {
-  return Object.defineProperty(() => session().ready(), "promise", {
-    get: () => session().ready.promise,
-  }) as (() => boolean) & { readonly promise: Promise<unknown> | undefined }
-}
-
-function promptStore(): PromptStore {
-  return {
-    prompt: clonePrompt(DEFAULT_PROMPT),
-    cursor: undefined,
-    context: {
-      items: [],
-    },
-  }
-}
-
-function createPromptStateValue(store: PromptStore, setStore: SetStoreFunction<PromptStore>) {
-  const actions = createPromptActions(setStore)
-
-  const value = {
-    current: () => store.prompt,
-    cursor: createMemo(() => store.cursor),
-    dirty: () => !isPromptEqual(store.prompt, DEFAULT_PROMPT),
-    context: {
-      items: createMemo(() => store.context.items),
-      add(item: ContextItem) {
-        const key = contextItemKey(item)
-        if (store.context.items.find((x) => x.key === key)) return
-        setStore("context", "items", (items) => [...items, { key, ...item }])
-      },
-      remove(key: string) {
-        setStore("context", "items", (items) => items.filter((x) => x.key !== key))
-      },
-      removeComment(path: string, commentID: string) {
-        setStore("context", "items", (items) =>
-          items.filter((item) => !(item.type === "file" && item.path === path && item.commentID === commentID)),
-        )
-      },
-      updateComment(path: string, commentID: string, next: Partial<FileContextItem> & { comment?: string }) {
-        setStore("context", "items", (items) =>
-          items.map((item) => {
-            if (item.type !== "file" || item.path !== path || item.commentID !== commentID) return item
-            const value = { ...item, ...next }
-            return { ...value, key: contextItemKey(value) }
-          }),
-        )
-      },
-      replaceComments(items: FileContextItem[]) {
-        setStore("context", "items", (current) => [
-          ...current.filter((item) => !isCommentItem(item)),
-          ...items.map((item) => ({ ...item, key: contextItemKey(item) })),
-        ])
-      },
-    },
-    set: actions.set,
-    reset: actions.reset,
-    capture: () => value,
-  }
-  return value
-}
-
-export function createPromptState() {
-  const [store, setStore] = createStore<PromptStore>(promptStore())
-  const ready = Object.assign(() => true, { promise: Promise.resolve(true) })
-  return {
-    ready,
-    ...createPromptStateValue(store, setStore),
-  }
-}
-
 export const createTabPromptState = (
   tabs: ReturnType<typeof useTabs>,
   tab: Tab,
@@ -303,9 +81,7 @@ export const { use: usePrompt, provider: PromptProvider } = createSimpleContext(
     const cache = new Map<string, PromptCacheEntry>()
 
     const disposeAll = () => {
-      for (const entry of cache.values()) {
-        entry.dispose()
-      }
+      for (const entry of cache.values()) entry.dispose()
       cache.clear()
     }
 
@@ -324,13 +100,11 @@ export const { use: usePrompt, provider: PromptProvider } = createSimpleContext(
     const owner = getOwner()
     const serverKey = () =>
       params.serverKey ? requireServerKey(params.serverKey) : ServerConnection.key(serverSDK().server)
-    const scope = () =>
+    const scope = (): PromptScope =>
       search.draftId ? { draftID: search.draftId } : { dir: base64Encode(sdk().directory), id: params.id }
-    const load = (scope: Scope) => {
+    const load = (scope: PromptScope) => {
       const current = settings.general.newLayoutDesigns() ? selectPromptTab(tabs.store, scope, serverKey()) : undefined
-      if (current) {
-        return createTabPromptState(tabs, current, serverSDK().scope, scope)
-      }
+      if (current) return createTabPromptState(tabs, current, serverSDK().scope, scope)
 
       const key = scopeKey(scope)
       const existing = cache.get(key)
@@ -354,15 +128,19 @@ export const { use: usePrompt, provider: PromptProvider } = createSimpleContext(
     }
 
     const session = createMemo(() => load(scope()))
-    const pick = (scope?: Scope) => (scope ? load(scope) : session())
+    const pick = (scope?: PromptScope) => (scope ? load(scope) : session())
     const ready = createPromptReady(session)
 
     return {
       ready,
-      capture: (scope?: Scope) => pick(scope).capture(),
+      capture: (scope?: PromptScope) => pick(scope).capture(),
       current: () => session().current(),
       cursor: () => session().cursor(),
       dirty: () => session().dirty(),
+      model: {
+        current: () => session().model.current(),
+        set: (model: PromptModel | undefined) => session().model.set(model),
+      },
       context: {
         items: () => session().context.items(),
         add: (item: ContextItem) => session().context.add(item),
@@ -372,8 +150,8 @@ export const { use: usePrompt, provider: PromptProvider } = createSimpleContext(
           session().context.updateComment(path, commentID, next),
         replaceComments: (items: FileContextItem[]) => session().context.replaceComments(items),
       },
-      set: (prompt: Prompt, cursorPosition?: number, scope?: Scope) => pick(scope).set(prompt, cursorPosition),
-      reset: (scope?: Scope) => pick(scope).reset(),
+      set: (prompt: Prompt, cursorPosition?: number, scope?: PromptScope) => pick(scope).set(prompt, cursorPosition),
+      reset: (scope?: PromptScope) => pick(scope).reset(),
     }
   },
 })

packages/app/src/context/tab-memory.ts

@@ -16,6 +16,9 @@ export function createTabMemory(owner: Owner | null) {
   }
 
   return {
+    get<T>(key: string, name: string) {
+      return entries.get(key)?.get(name)?.value as T | undefined
+    },
     ensure<T>(key: string, name: string, init: () => T) {
       const state = entries.get(key) ?? new Map<string, Entry>()
       if (!entries.has(key)) entries.set(key, state)

packages/app/src/context/tabs.test.ts

@@ -22,6 +22,8 @@ describe("tab memory", () => {
       })
 
       expect(memory.ensure("tab", "prompt", () => ({ value: "other" }))).toBe(first)
+      expect(memory.get<typeof first>("tab", "prompt")).toBe(first)
+      expect(memory.get("missing", "prompt")).toBeUndefined()
       expect(memory.ensure("other", "prompt", () => ({ value: "other" }))).not.toBe(first)
 
       memory.remove("tab")

packages/app/src/context/tabs.tsx

@@ -11,6 +11,7 @@ import { SessionTabsRemovedDetail } from "@/components/titlebar-session-events"
 import { sessionHref } from "@/utils/session-route"
 import { createTabMemory } from "./tab-memory"
 import { nextTabAfterClose, pushClosedTab, removeClosedTabs, takeClosedTab, type ClosedTab } from "./closed-tabs"
+import { createDraftPromptSession, type PromptModel } from "./prompt-state"
 
 export type SessionTab = {
   type: "session"
@@ -207,15 +208,17 @@ export const { use: useTabs, provider: TabsProvider } = createSimpleContext({
         if (!tab || tab.type !== "draft") throw new Error(`Draft not found: ${draftID}`)
         return tab
       },
-      newDraft(draft: Omit<DraftTab, "type" | "draftID">, prompt?: string) {
+      newDraft(draft: Omit<DraftTab, "type" | "draftID">, prompt?: string, model?: PromptModel) {
         const draftID = uuid()
+        const tab = { type: "draft" as const, draftID, ...draft }
+        memory.ensure(tabKey(tab), "prompt", () => createDraftPromptSession(draftID, { prompt, model }))
         void startTransition(() => {
           setStore(
             produce((tabs) => {
-              tabs.push({ type: "draft", draftID, ...draft })
+              tabs.push(tab)
             }),
           )
-          navigate(prompt ? `${draftHref(draftID)}&prompt=${encodeURIComponent(prompt)}` : draftHref(draftID))
+          navigate(draftHref(draftID))
         })
       },
       updateDraft(draftID: string, draft: Partial<Omit<DraftTab, "type" | "draftID">>) {
@@ -373,6 +376,9 @@ export const { use: useTabs, provider: TabsProvider } = createSimpleContext({
       state<T>(tab: Tab, name: string, init: () => T) {
         return memory.ensure(tabKey(tab), name, init)
       },
+      stateValue<T>(tab: Tab, name: string) {
+        return memory.get<T>(tabKey(tab), name)
+      },
     }
 
     return { ...actions, store, info, ready, recentReady }

packages/app/src/pages/new-session.tsx

@@ -26,10 +26,13 @@ import { useComposerCommands } from "@/pages/session/use-composer-commands"
 import { NEW_SESSION_CONTENT_WIDTH } from "@/pages/session/new-session-layout"
 import { PromptWorkspaceSelector } from "@/components/prompt-workspace-selector"
 import { useTitlebarRightMount } from "@/components/titlebar"
+import { useCommand } from "@/context/command"
 import { useProviders } from "@/hooks/use-providers"
 import { useSettingsDialog } from "@/components/settings-dialog"
 import { Persist, persisted } from "@/utils/persist"
 import createPresence from "solid-presence"
+import { useLocal } from "@/context/local"
+import { createPromptModelSelection } from "@/pages/session/composer/prompt-model-selection"
 
 const workspaceBarEnabled = import.meta.env.VITE_OPENCODE_CHANNEL !== "prod"
 const providerTipDismissalDuration = 30 * 24 * 60 * 60 * 1000
@@ -48,12 +51,15 @@ export default function NewSessionPage() {
   const comments = useComments()
   const language = useLanguage()
   const settings = useSettings()
+  const command = useCommand()
   const providers = useProviders(() => sdk().directory)
   const openProviderSettings = useSettingsDialog("providers")
   const route = useSessionKey()
   const [searchParams, setSearchParams] = useSearchParams<{ draftId?: string; prompt?: string }>()
+  const local = useLocal()
+  const model = createPromptModelSelection({ agent: local.agent.current })
 
-  useComposerCommands()
+  useComposerCommands({ model })
 
   let inputRef: HTMLDivElement | undefined
 
@@ -61,6 +67,7 @@ export default function NewSessionPage() {
     sessionKey: route.sessionKey,
     sessionID: () => route.params.id,
     queryOptions: serverSync().queryOptions,
+    model,
   })
   const projectControls = createPromptProjectControls()
   const projectController = createPromptProjectController({
@@ -68,6 +75,16 @@ export default function NewSessionPage() {
     onDone: () => inputRef?.focus(),
   })
 
+  command.register("new-session", () => [
+    {
+      id: "input.focus",
+      title: language.t("command.input.focus"),
+      category: language.t("command.category.view"),
+      keybind: "ctrl+l",
+      onSelect: () => inputRef?.focus(),
+    },
+  ])
+
   const [store, setStore] = createStore<{ worktree?: string }>({})
   const rightMount = useTitlebarRightMount()
 

packages/app/src/pages/session.tsx

@@ -69,7 +69,7 @@ import { MessageTimeline } from "@/pages/session/timeline/message-timeline"
 import { createTimelineModel } from "@/pages/session/timeline/model"
 import { type DiffStyle, SessionReviewTab, type SessionReviewTabProps } from "@/pages/session/review-tab"
 import { useSessionLayout } from "@/pages/session/session-layout"
-import { syncSessionModel } from "@/pages/session/session-model-helpers"
+import { restorePromptModel, syncPromptModel, syncSessionModel } from "@/pages/session/session-model-helpers"
 import {
   clampSessionPanelWidth,
   SESSION_PANEL_WIDTH_MIN,
@@ -483,7 +483,7 @@ export default function Page() {
     if (desktopSessionResizeOpen()) return `${sessionPanelResizedWidth()}px`
     return `calc(100% - ${layout.fileTree.width()}px)`
   })
-  const centered = createMemo(() => isDesktop() && !desktopReviewOpen())
+  const centered = createMemo(() => isDesktop() && (newSessionDesign() || !desktopReviewOpen()))
   const desktopV2PanelLayout = createMemo(() =>
     sessionPanelLayout({
       review: desktopV2ReviewOpen(),
@@ -557,6 +557,17 @@ export default function Page() {
     ),
   )
 
+  let restoredModelSession: string | undefined
+  createEffect(() => {
+    const id = params.id
+    if (!id || !prompt.ready() || !local.session.ready()) return
+    if (restoredModelSession !== id) {
+      restoredModelSession = id
+      if (restorePromptModel(local, prompt)) return
+    }
+    syncPromptModel(local, prompt)
+  })
+
   createEffect(
     on(
       () => ({ dir: sdk().directory, id: params.id }),
@@ -1267,7 +1278,7 @@ export default function Page() {
   const reviewPanelV2Rendered = createMemo<boolean>((prev) => prev || !store.deferRender, false)
 
   const reviewPanelV2 = () => (
-    <div class="flex flex-col h-full overflow-hidden bg-background-stronger contain-strict">
+    <div class="flex flex-col h-full overflow-hidden bg-v2-background-bg-base contain-strict">
       <Show when={reviewPanelV2Rendered()}>
         <ReviewPanelV2 {...reviewPanelV2Props()} />
       </Show>

packages/app/src/pages/session/composer/prompt-model-selection.ts

@@ -0,0 +1,133 @@
+import { batch, createMemo, startTransition } from "solid-js"
+import { useModels } from "@/context/models"
+import type { ModelKey, ModelSelection } from "@/context/local"
+import { cycleModelVariant, getConfiguredAgentVariant, resolveModelVariant } from "@/context/model-variant"
+import { usePrompt } from "@/context/prompt"
+import { useSDK } from "@/context/sdk"
+import { useSync } from "@/context/sync"
+import { useProviders } from "@/hooks/use-providers"
+
+export function createPromptModelSelection(input: { agent: () => { model?: ModelKey; variant?: string } | undefined }) {
+  const sdk = useSDK()
+  const sync = useSync()
+  const models = useModels()
+  const prompt = usePrompt()
+  const providers = useProviders(() => sdk().directory)
+  const connected = createMemo(() => new Set(providers.connected().map((item) => item.id)))
+
+  const valid = (model: ModelKey) => {
+    const provider = providers.all().get(model.providerID)
+    return !!provider?.models[model.modelID] && connected().has(model.providerID)
+  }
+
+  const configured = () => {
+    const value = sync().data.config.model
+    if (!value) return
+    const [providerID, modelID] = value.split("/")
+    const model = { providerID, modelID }
+    if (valid(model)) return model
+  }
+
+  const recent = () => models.recent.list().find(valid)
+  const fallback = () => {
+    const defaults = providers.default()
+    return providers.connected().flatMap((provider) => {
+      const modelID = defaults[provider.id] ?? Object.values(provider.models)[0]?.id
+      return modelID ? [{ providerID: provider.id, modelID }] : []
+    })[0]
+  }
+
+  const current = () => {
+    const key = [prompt.model.current(), input.agent()?.model, configured(), recent(), fallback()].find(
+      (item): item is ModelKey => !!item && valid(item),
+    )
+    if (!key) return
+    return models.find(key)
+  }
+  const recentModels = createMemo(() =>
+    models.recent
+      .list()
+      .map(models.find)
+      .filter((item): item is NonNullable<typeof item> => !!item),
+  )
+
+  const selection = {
+    ready: models.ready,
+    current,
+    recent: recentModels,
+    list: models.list,
+    cycle(direction: 1 | -1) {
+      const items = recentModels()
+      const item = current()
+      if (!item) return
+      const index = items.findIndex((entry) => entry.provider.id === item.provider.id && entry.id === item.id)
+      if (index === -1) return
+      const next = items[(index + direction + items.length) % items.length]
+      if (next) selection.set({ providerID: next.provider.id, modelID: next.id })
+    },
+    set(item: ModelKey | undefined, options?: { recent?: boolean }) {
+      startTransition(() =>
+        batch(() => {
+          prompt.model.set(item ? { ...item, variant: prompt.model.current()?.variant } : undefined)
+          if (!item) return
+          models.setVisibility(item, true)
+          if (options?.recent) models.recent.push(item)
+        }),
+      )
+    },
+    visible: models.visible,
+    setVisibility: models.setVisibility,
+    variant: {
+      configured() {
+        const item = input.agent()
+        const model = current()
+        if (!item || !model) return
+        return getConfiguredAgentVariant({
+          agent: { model: item.model, variant: item.variant },
+          model: { providerID: model.provider.id, modelID: model.id, variants: model.variants },
+        })
+      },
+      selected() {
+        return prompt.model.current()?.variant
+      },
+      current() {
+        const resolved = resolveModelVariant({
+          variants: this.list(),
+          selected: this.selected(),
+          configured: this.configured(),
+        })
+        if (resolved) return resolved
+        const model = current()
+        if (!model) return
+        const saved = models.variant.get({ providerID: model.provider.id, modelID: model.id })
+        if (saved && this.list().includes(saved)) return saved
+      },
+      list() {
+        return Object.keys(current()?.variants ?? {})
+      },
+      set(value: string | undefined) {
+        startTransition(() =>
+          batch(() => {
+            const model = current()
+            if (!model) return
+            prompt.model.set({ providerID: model.provider.id, modelID: model.id, variant: value ?? null })
+            models.variant.set({ providerID: model.provider.id, modelID: model.id }, value)
+          }),
+        )
+      },
+      cycle() {
+        const variants = this.list()
+        if (variants.length === 0) return
+        this.set(
+          cycleModelVariant({
+            variants,
+            selected: this.selected(),
+            configured: this.configured(),
+          }),
+        )
+      },
+    },
+  } satisfies ModelSelection
+
+  return selection
+}

packages/app/src/pages/session/composer/session-composer-controls.ts

@@ -7,7 +7,7 @@ import type { PromptProjectControls } from "@/components/prompt-project-selector
 import { useDirectoryPicker } from "@/components/directory-picker"
 import { useGlobal } from "@/context/global"
 import { useLayout } from "@/context/layout"
-import { useLocal } from "@/context/local"
+import { useLocal, type ModelSelection } from "@/context/local"
 import type { QueryOptionsApi } from "@/context/server-sync"
 import { useServerSDK } from "@/context/server-sdk"
 import { serverName, ServerConnection, useServer } from "@/context/server"
@@ -22,6 +22,7 @@ export function createPromptInputController(input: {
   sessionKey: Accessor<string>
   sessionID: Accessor<string | undefined>
   queryOptions: Pick<QueryOptionsApi, "agents" | "providers">
+  model?: ModelSelection
 }) {
   const layout = useLayout()
   const local = useLocal()
@@ -44,7 +45,7 @@ export function createPromptInputController(input: {
       select: local.agent.set,
     },
     model: {
-      selection: local.model,
+      selection: input.model ?? local.model,
       paid: providers.paid().length > 0,
       loading: agentsQuery.isLoading || providersQuery.isLoading || globalProvidersQuery.isLoading,
     },

packages/app/src/pages/session/session-model-helpers.test.ts

@@ -1,6 +1,6 @@
 import { describe, expect, test } from "bun:test"
 import type { UserMessage } from "@opencode-ai/sdk/v2"
-import { resetSessionModel, syncSessionModel } from "./session-model-helpers"
+import { resetSessionModel, restorePromptModel, syncPromptModel, syncSessionModel } from "./session-model-helpers"
 
 const message = (input?: { agent?: string; model?: UserMessage["model"] }) =>
   ({
@@ -50,3 +50,102 @@ describe("resetSessionModel", () => {
     expect(calls).toEqual(["reset"])
   })
 })
+
+describe("syncPromptModel", () => {
+  test("stores the effective session model in prompt state", () => {
+    const calls: unknown[] = []
+
+    syncPromptModel(
+      {
+        model: {
+          current: () => ({ id: "claude-sonnet-4", provider: { id: "anthropic" } }),
+          set() {},
+          variant: { current: () => "high", set() {} },
+        },
+      },
+      {
+        model: {
+          current: () => undefined,
+          set: (model) => calls.push(model),
+        },
+      },
+    )
+
+    expect(calls).toEqual([{ providerID: "anthropic", modelID: "claude-sonnet-4", variant: "high" }])
+  })
+
+  test("does not rewrite an unchanged prompt model", () => {
+    const calls: unknown[] = []
+    const model = { providerID: "anthropic", modelID: "claude-sonnet-4", variant: "high" }
+
+    syncPromptModel(
+      {
+        model: {
+          current: () => ({ id: model.modelID, provider: { id: model.providerID } }),
+          set() {},
+          variant: { current: () => model.variant, set() {} },
+        },
+      },
+      {
+        model: {
+          current: () => model,
+          set: (value) => calls.push(value),
+        },
+      },
+    )
+
+    expect(calls).toEqual([])
+  })
+})
+
+describe("restorePromptModel", () => {
+  test("restores the persisted prompt model into session selection", () => {
+    const calls: unknown[] = []
+    const restored = restorePromptModel(
+      {
+        model: {
+          current: () => ({ id: "gpt", provider: { id: "openai" } }),
+          set: (model) => calls.push(model),
+          variant: {
+            current: () => undefined,
+            set: (variant) => calls.push(variant),
+          },
+        },
+      },
+      {
+        model: {
+          current: () => ({ providerID: "anthropic", modelID: "claude", variant: "high" }),
+          set() {},
+        },
+      },
+    )
+
+    expect(restored).toBe(true)
+    expect(calls).toEqual([{ providerID: "anthropic", modelID: "claude" }, "high"])
+  })
+
+  test("does nothing without a persisted prompt model", () => {
+    const calls: unknown[] = []
+    const restored = restorePromptModel(
+      {
+        model: {
+          current: () => ({ id: "gpt", provider: { id: "openai" } }),
+          set: (model) => calls.push(model),
+          variant: {
+            current: () => undefined,
+            set: (variant) => calls.push(variant),
+          },
+        },
+      },
+      {
+        model: {
+          current: () => undefined,
+          set() {},
+        },
+      },
+    )
+
+    expect(restored).toBe(false)
+    expect(calls).toEqual([])
+  })
+})

packages/app/src/pages/session/session-model-helpers.ts

@@ -7,6 +7,24 @@ type Local = {
   }
 }
 
+type ModelSelection = {
+  model: {
+    current(): { id: string; provider: { id: string } } | undefined
+    set(model: { providerID: string; modelID: string }): void
+    variant: {
+      current(): string | undefined
+      set(variant: string | undefined): void
+    }
+  }
+}
+
+type PromptState = {
+  model: {
+    current(): { providerID: string; modelID: string; variant?: string | null } | undefined
+    set(model: { providerID: string; modelID: string; variant?: string | null }): void
+  }
+}
+
 export const resetSessionModel = (local: Local) => {
   local.session.reset()
 }
@@ -14,3 +32,32 @@ export const resetSessionModel = (local: Local) => {
 export const syncSessionModel = (local: Local, msg: UserMessage) => {
   local.session.restore(msg)
 }
+
+export const syncPromptModel = (local: ModelSelection, prompt: PromptState) => {
+  const model = local.model.current()
+  if (!model) return
+  const next = {
+    providerID: model.provider.id,
+    modelID: model.id,
+    variant: local.model.variant.current(),
+  }
+  const current = prompt.model.current()
+  if (current?.providerID === next.providerID && current.modelID === next.modelID && current.variant === next.variant)
+    return
+  prompt.model.set(next)
+}
+
+export const restorePromptModel = (local: ModelSelection, prompt: PromptState) => {
+  const model = prompt.model.current()
+  if (!model) return false
+  const current = local.model.current()
+  if (
+    current?.provider.id === model.providerID &&
+    current.id === model.modelID &&
+    local.model.variant.current() === (model.variant ?? undefined)
+  )
+    return true
+  local.model.set({ providerID: model.providerID, modelID: model.modelID })
+  local.model.variant.set(model.variant ?? undefined)
+  return true
+}

packages/app/src/pages/session/session-side-panel.tsx

@@ -249,8 +249,10 @@ export function SessionSidePanel(props: {
         aria-label={language.t("session.panel.reviewAndFiles")}
         aria-hidden={!open()}
         inert={!open()}
-        class="relative min-w-0 flex overflow-hidden bg-background-base"
+        class="relative min-w-0 flex overflow-hidden"
         classList={{
+          "bg-v2-background-bg-base": settings.general.newLayoutDesigns(),
+          "bg-background-base": !settings.general.newLayoutDesigns(),
           "h-full shrink-0": !props.stacked,
           "h-full min-h-0": props.stacked,
           "pointer-events-none": !open(),
@@ -269,8 +271,20 @@ export function SessionSidePanel(props: {
             }}
           >
             <Show when={reviewOpen()}>
-              <div class="relative min-w-0 h-full flex-1 overflow-hidden bg-background-base">
-                <div class="size-full min-w-0 h-full bg-background-base">
+              <div
+                class="relative min-w-0 h-full flex-1 overflow-hidden"
+                classList={{
+                  "bg-v2-background-bg-base": settings.general.newLayoutDesigns(),
+                  "bg-background-base": !settings.general.newLayoutDesigns(),
+                }}
+              >
+                <div
+                  class="size-full min-w-0 h-full"
+                  classList={{
+                    "bg-v2-background-bg-base": settings.general.newLayoutDesigns(),
+                    "bg-background-base": !settings.general.newLayoutDesigns(),
+                  }}
+                >
                   <DragDropProvider
                     onDragStart={handleDragStart}
                     onDragEnd={handleDragEnd}
@@ -373,7 +387,13 @@ export function SessionSidePanel(props: {
                               )}
                             </For>
                           </SortableProvider>
-                          <div class="bg-background-stronger h-full shrink-0 sticky right-0 z-10 flex items-center justify-center pr-3">
+                          <div
+                            class="h-full shrink-0 sticky right-0 z-10 flex items-center justify-center pr-3"
+                            classList={{
+                              "bg-v2-background-bg-base": settings.general.newLayoutDesigns(),
+                              "bg-background-stronger": !settings.general.newLayoutDesigns(),
+                            }}
+                          >
                             <TooltipKeybind
                               title={language.t("command.file.open")}
                               keybind={command.keybind("file.open")}

packages/app/src/pages/session/terminal-panel-v2.tsx

@@ -195,7 +195,7 @@ export function TerminalPanelV2(props: { stacked?: boolean } = {}) {
       aria-label={language.t("terminal.title")}
       aria-hidden={!opened()}
       inert={!opened()}
-      class="relative shrink-0 overflow-hidden bg-background-stronger"
+      class="relative shrink-0 overflow-hidden bg-v2-background-bg-base"
       classList={{
         "w-full": !isDesktop() || stacked(),
         "min-w-0 h-full flex-1": isDesktop() && opened() && !stacked(),
@@ -237,7 +237,7 @@ export function TerminalPanelV2(props: { stacked?: boolean } = {}) {
           when={terminal.ready()}
           fallback={
             <div class="flex flex-col h-full pointer-events-none">
-              <div class="h-10 flex items-center gap-2 px-2 border-b border-border-weaker-base bg-background-stronger overflow-hidden">
+              <div class="h-10 flex items-center gap-2 px-2 border-b border-border-weaker-base bg-v2-background-bg-base overflow-hidden">
                 <For each={handoff()}>
                   {(title) => (
                     <div class="px-2 py-1 rounded-md bg-surface-base text-14-regular text-text-weak truncate max-w-40">

packages/app/src/pages/session/timeline/message-timeline.tsx

@@ -1243,12 +1243,13 @@ export function MessageTimeline(props: {
     const initialRow = timelineRowByKey().get(props.rowKey)!
     const item = createMemo(() => virtualItemByKey().get(props.rowKey) ?? initialItem)
     const row = createMemo(() => timelineRowByKey().get(props.rowKey) ?? initialRow)
-    const asyncFile = () => {
+    const tool = () => {
       const value = row()
-      if (value._tag !== "AssistantPart" || value.group.type !== "part") return false
+      if (value._tag !== "AssistantPart" || value.group.type !== "part") return
       const part = getMsgPart(value.group.ref.messageID, value.group.ref.partID)
-      return part?.type === "tool" && ["edit", "write", "patch", "apply_patch"].includes(part.tool)
+      if (part?.type === "tool") return part
     }
+    const asyncFile = () => ["edit", "write", "patch", "apply_patch"].includes(tool()?.tool ?? "")
     const [ready, setReady] = createSignal(initialItem.size <= timelineFallbackItemSize || !asyncFile())
     let contentMeasureFrame: number | undefined
 
@@ -1278,6 +1279,8 @@ export function MessageTimeline(props: {
           width: "100%",
           height: `${item().size}px`,
           overflow: "clip",
+          // Rounded virtual measurements can otherwise clip a framed row's outer paint.
+          "overflow-clip-margin": row()._tag === "TurnGap" ? undefined : "0.5px",
         }}
       >
         <div
@@ -1383,7 +1386,7 @@ export function MessageTimeline(props: {
               "w-full": true,
               "pb-4": true,
               "pr-3": true,
-              "pl-2": settings.general.newLayoutDesigns(),
+              "pl-2.5": settings.general.newLayoutDesigns(),
               "pl-2 md:pl-4": !settings.general.newLayoutDesigns(),
               "md:max-w-200 md:mx-auto 2xl:max-w-[1000px]": props.centered && !settings.general.newLayoutDesigns(),
             }}

packages/app/src/pages/session/use-composer-commands.tsx

@@ -1,6 +1,6 @@
 import { useCommand, type CommandOption } from "@/context/command"
 import { useLanguage } from "@/context/language"
-import { useLocal } from "@/context/local"
+import { useLocal, type ModelSelection } from "@/context/local"
 import { useSettings } from "@/context/settings"
 import { useDialog } from "@opencode-ai/ui/context/dialog"
 import { getCursorPosition, setCursorPosition } from "@/components/prompt-input/editor-dom"
@@ -14,7 +14,7 @@ const withCategory = (category: string) => {
   })
 }
 
-export const useComposerCommands = () => {
+export const useComposerCommands = (input: { model?: ModelSelection } = {}) => {
   const command = useCommand()
   const dialog = useDialog()
   const language = useLanguage()
@@ -22,6 +22,7 @@ export const useComposerCommands = () => {
   const settings = useSettings()
   const { sessionKey } = useSessionLayout()
   const sessionOwnership = createSessionOwnership(sessionKey)
+  const model = input.model ?? local.model
   const modelCommand = withCategory(language.t("command.category.model"))
   const agentCommand = withCategory(language.t("command.category.agent"))
 
@@ -43,7 +44,7 @@ export const useComposerCommands = () => {
     }
     const { DialogSelectModel } = await import("@/components/dialog-select-model")
     owner.run(() => {
-      void dialog.show(() => <DialogSelectModel model={local.model} />, restoreComposer)
+      void dialog.show(() => <DialogSelectModel model={model} />, restoreComposer)
     })
   }
 
@@ -61,7 +62,7 @@ export const useComposerCommands = () => {
       title: language.t("command.model.variant.cycle"),
       description: language.t("command.model.variant.cycle.description"),
       keybind: "shift+mod+d",
-      onSelect: () => local.model.variant.cycle(),
+      onSelect: () => model.variant.cycle(),
     }),
     agentCommand({
       id: "agent.cycle",

packages/app/src/pages/session/v2/session-file-browser-tab.tsx

@@ -46,6 +46,7 @@ export function SessionFileBrowserTab(props: {
   const resultsID = `session-file-browser-results-${createUniqueId()}`
   const [filter, setFilter] = createSignal("")
   const [explicitHighlight, setExplicitHighlight] = createSignal<string>()
+  const sidebarOpened = () => props.placeholder || props.state.sidebarOpened()
   const query = createMemo(() => filter().trim())
   const search = createQuery(() => {
     const value = query()
@@ -98,15 +99,15 @@ export function SessionFileBrowserTab(props: {
         toolbar
         toolbarStart={
           <>
-            <SessionReviewV2SidebarToggle opened={props.state.sidebarOpened()} onToggle={props.state.toggleSidebar} />
-            <Show when={!props.state.sidebarOpened()}>
+            <SessionReviewV2SidebarToggle opened={sidebarOpened()} onToggle={props.state.toggleSidebar} />
+            <Show when={!sidebarOpened()}>
               <SessionFilePanelV2Title>{title()}</SessionFilePanelV2Title>
             </Show>
           </>
         }
         sidebar={
           <SessionReviewV2Sidebar
-            open={props.state.sidebarOpened()}
+            open={sidebarOpened()}
             title={<span class="truncate">{title()}</span>}
             filter={filter()}
             onFilterChange={setFilter}

packages/app/src/utils/persist.ts

@@ -463,7 +463,7 @@ function localStorageDirect(): SyncStorage {
   }
 }
 
-const DRAFT_PERSISTED_KEYS = ["prompt", "comments", "model-selection", "file-view", "layout"]
+const DRAFT_PERSISTED_KEYS = ["prompt", "comments", "file-view", "layout"]
 
 export function draftPersistedKeys() {
   return DRAFT_PERSISTED_KEYS

packages/cli/bunfig.toml

@@ -1 +1,4 @@
 preload = ["@opentui/solid/preload"]
+
+[test]
+preload = ["@opentui/solid/preload"]

packages/cli/src/commands/handlers/default.ts

@@ -2,12 +2,13 @@ import { AppNodeBuilder } from "@opencode-ai/core/effect/app-node-builder"
 import { Global } from "@opencode-ai/core/global"
 import { run } from "@opencode-ai/tui"
 import { loadBuiltinPlugins } from "@opencode-ai/tui/builtins"
-import { TuiConfig } from "@opencode-ai/tui/config"
 import { Commands } from "../commands"
 import { Runtime } from "../../framework/runtime"
+import { TuiConfig } from "../../tui-config"
 import { Effect, Option } from "effect"
 import { Server } from "../../services/server"
 import { Updater } from "../../services/updater"
+import { UpdatePreflight } from "../../services/update-preflight"
 
 export default Runtime.handler(Commands, (input) =>
   Effect.gen(function* () {
@@ -15,17 +16,33 @@ export default Runtime.handler(Commands, (input) =>
     if (requestedDirectory !== undefined) process.chdir(requestedDirectory)
     const updater = yield* Updater.Service
     yield* updater.check().pipe(Effect.forkScoped)
+    const preflight = UpdatePreflight.make()
+    yield* Effect.addFinalizer(() => Effect.promise(() => preflight.close()))
     const server = yield* Server.resolve({
       server: Option.getOrUndefined(input.server),
       standalone: input.standalone,
-    })
-    const config = TuiConfig.resolve({}, { terminalSuspend: false })
+      onStart: (reason, existing) => {
+        if (reason === "version-mismatch" && preflight.begin(existing?.version)) return
+        process.stderr.write(
+          reason === "version-mismatch"
+            ? "Restarting background server (version mismatch)...\n"
+            : "Starting background server...\n",
+        )
+      },
+    }).pipe(
+      Effect.tapError(() =>
+        Effect.promise(() => preflight.fail("OpenCode update could not start the new background service")),
+      ),
+    )
+    preflight.loading()
+    const config = yield* TuiConfig.load()
     let disposeSlots: (() => void) | undefined
     const runFork = Effect.runForkWith(yield* Effect.context())
     yield* run({
       server,
       args: { continue: input.continue, sessionID: Option.getOrUndefined(input.session) },
       config,
+      terminalHandoff: () => preflight.finish(),
       log: (level, message, tags) => {
         const effect =
           level === "debug"

packages/cli/src/mini/footer.prompt.tsx

@@ -778,19 +778,26 @@ export function createPromptState(input: PromptInput): PromptState {
     if (!area || area.isDestroyed) return false
 
     const endOffset = Bun.stringWidth(area.plainText)
-    if (dir === -1 && area.visualCursor.visualRow === 0) {
-      area.cursorOffset = 0
+    if (dir === -1) {
+      if (area.cursorOffset === 0) return false
+      if (area.visualCursor.visualRow === 0) {
+        area.cursorOffset = 0
+        return
+      }
+      area.moveCursorUp()
+      return
     }
 
     const end =
       typeof area.height === "number" && Number.isFinite(area.height) && area.height > 0
         ? area.height - 1
         : Math.max(0, (area.virtualLineCount ?? 1) - 1)
-    if (dir === 1 && area.visualCursor.visualRow === end) {
+    if (area.cursorOffset === endOffset) return false
+    if (area.visualCursor.visualRow === end) {
       area.cursorOffset = endOffset
+      return
     }
-
-    return false
+    area.moveCursorDown()
   }
 
   const requestExit = () => {
@@ -1037,6 +1044,7 @@ export function createPromptState(input: PromptInput): PromptState {
   }))
 
   useBindings(() => ({
+    priority: 1,
     mode: OPENCODE_BASE_MODE,
     enabled: input.prompt() && !visible(),
     commands: [

packages/cli/src/mini/runtime.boot.ts

@@ -6,7 +6,7 @@
 // history ring. All are async because they read config or hit the SDK, but
 // none block each other.
 import { Context, Effect, Layer } from "effect"
-import { resolve } from "@opencode-ai/tui/config"
+import { resolve } from "@opencode-ai/tui/config/v1"
 import { AppNodeBuilder } from "@opencode-ai/core/effect/app-node-builder"
 import { makeGlobalNode } from "@opencode-ai/core/effect/app-node"
 import { makeRuntime } from "@opencode-ai/core/effect/runtime"

packages/cli/src/mini/types.ts

@@ -13,7 +13,7 @@
 //         → OpenTUI split-footer renderer writes to terminal
 import type { OpenCodeClient, ReferenceListOutput } from "@opencode-ai/client/promise"
 import type { FilePart, PermissionRequest, QuestionRequest, ToolPart } from "@opencode-ai/sdk/v2"
-import type { TuiConfig } from "@opencode-ai/tui/config"
+import type { TuiConfig } from "@opencode-ai/tui/config/v1"
 
 export type RunFilePart = {
   type: "file"

packages/cli/src/services/server.ts

@@ -11,6 +11,7 @@ export type Args = {
   readonly server?: string
   readonly standalone?: boolean
   readonly mismatch?: "replace" | "ignore" | "error"
+  readonly onStart?: Service.StartOptions["onStart"]
 }
 
 export type Resolved = {
@@ -46,7 +47,7 @@ export const resolve = Effect.fn("cli.server.resolve")(function* (args: Args) {
   }
 
   const options = yield* ServiceConfig.options()
-  const endpoint = yield* resolveManaged(options, args.mismatch ?? "replace")
+  const endpoint = yield* resolveManaged({ ...options, onStart: args.onStart }, args.mismatch ?? "replace")
   const reconnectOptions = { ...options, version: undefined }
   return {
     endpoint,
@@ -70,7 +71,7 @@ export const resolve = Effect.fn("cli.server.resolve")(function* (args: Args) {
 })
 
 const resolveManaged = Effect.fnUntraced(function* (
-  options: Service.Options,
+  options: Service.StartOptions,
   mismatch: NonNullable<Args["mismatch"]>,
 ) {
   if (mismatch === "replace") return yield* Service.start(options)

packages/cli/src/services/update-preflight.tsx

@@ -0,0 +1,494 @@
+/** @jsxImportSource @opentui/solid */
+// Split-footer status shown while a freshly launched CLI replaces a
+// version-mismatched background service before the TUI attaches.
+import { createCliRenderer, RGBA, TextAttributes, type CliRenderer, type ThemeMode } from "@opentui/core"
+import { render, useTerminalDimensions } from "@opentui/solid"
+import { InstallationVersion } from "@opencode-ai/core/installation/version"
+import { registerOpencodeSpinner } from "@opencode-ai/tui/component/register-spinner"
+import { SPINNER_FRAMES } from "@opencode-ai/tui/component/spinner"
+import { go } from "@opencode-ai/tui/logo"
+import {
+  batch,
+  createEffect,
+  createMemo,
+  createSignal,
+  For,
+  Index,
+  on,
+  onCleanup,
+  onMount,
+  Show,
+  untrack,
+} from "solid-js"
+
+const stages = ["Keeping your session safe", "Starting the new background service", "Loading OpenCode"] as const
+const stageFloor = 480
+const transitionDuration = 420
+const completionHold = 650
+
+export type Handle = {
+  readonly begin: (from?: string) => boolean
+  readonly loading: () => void
+  readonly finish: () => Promise<Handoff | undefined>
+  readonly fail: (message: string) => Promise<void>
+  readonly close: () => Promise<void>
+}
+
+export type Handoff = {
+  readonly renderer: CliRenderer
+  readonly mode: ThemeMode | null
+  readonly complete: () => void
+}
+
+export const make = (): Handle => {
+  let session: Promise<Session | undefined> | undefined
+  return {
+    begin: (from) => {
+      if (!process.stdout.isTTY || !process.stdin.isTTY) return false
+      session ??= open(from).catch(() => {
+        process.stderr.write("Restarting background server (version mismatch)...\n")
+        return undefined
+      })
+      return true
+    },
+    loading: () => {
+      void session?.then((active) => active?.loading())
+    },
+    finish: async () => {
+      const active = await session
+      return active?.finish()
+    },
+    fail: async (message) => {
+      const active = await session
+      await active?.fail(message)
+    },
+    close: async () => {
+      const active = await session
+      await active?.close()
+    },
+  }
+}
+
+type Session = {
+  readonly loading: () => Promise<void>
+  readonly finish: () => Promise<Handoff>
+  readonly fail: (message: string) => Promise<void>
+  readonly close: () => Promise<void>
+}
+
+async function open(from?: string): Promise<Session> {
+  registerOpencodeSpinner()
+  const [active, setActive] = createSignal(0)
+  const [outcome, setOutcome] = createSignal<"running" | "success" | "failure">("running")
+  const [failure, setFailure] = createSignal("")
+  const [animating, setAnimating] = createSignal(true)
+  const [visible, setVisible] = createSignal(true)
+  let resolveOutcome: (() => void) | undefined
+  const renderer = await createCliRenderer({
+    stdin: process.stdin,
+    useMouse: false,
+    autoFocus: false,
+    openConsoleOnError: false,
+    exitOnCtrlC: false,
+    screenMode: "split-footer",
+    footerHeight: 4,
+    targetFps: 60,
+    useKittyKeyboard: {},
+    consoleOptions: {
+      keyBindings: [{ name: "y", ctrl: true, action: "copy-selection" }],
+    },
+    externalOutputMode: "capture-stdout",
+    consoleMode: "disabled",
+  })
+  const terminalMode = renderer.waitForThemeMode(1000).catch(() => null)
+  await render(
+    () => (
+      <Show when={visible()}>
+        <UpdateFooter
+          from={from}
+          active={active}
+          outcome={outcome}
+          failure={failure}
+          animating={animating}
+          renderer={renderer}
+          onOutcomeSettled={() => resolveOutcome?.()}
+        />
+      </Show>
+    ),
+    renderer,
+  ).catch((error) => {
+    if (!renderer.isDestroyed) renderer.destroy()
+    throw error
+  })
+  let shownAt = performance.now()
+  const waitForStage = async () => {
+    const remaining = stageFloor - (performance.now() - shownAt)
+    if (remaining > 0) await Bun.sleep(remaining)
+  }
+  const advance = async (stage: number) => {
+    await waitForStage()
+    if (outcome() !== "running") return
+    setActive(stage)
+    shownAt = performance.now()
+  }
+  // Service.start currently exposes only its start boundary, so this first
+  // transition is time-based. Finer lifecycle callbacks remain follow-up work.
+  const auto = advance(1)
+  const transitionTo = async (next: "success" | "failure", hold: number) => {
+    const settled = Promise.withResolvers<void>()
+    resolveOutcome = settled.resolve
+    setOutcome(next)
+    const completed = await Promise.race([
+      settled.promise.then(() => true),
+      Bun.sleep(transitionDuration + 500).then(() => false),
+    ])
+    resolveOutcome = undefined
+    setAnimating(false)
+    if (completed) await Bun.sleep(hold)
+  }
+  let closing: Promise<void> | undefined
+  let transferred = false
+  const close = () =>
+    (closing ??= (async () => {
+      if (transferred) return
+      setAnimating(false)
+      if (renderer.isDestroyed) return
+      renderer.pause()
+      await Promise.race([renderer.idle(), Bun.sleep(500)])
+      renderer.destroy()
+    })())
+  let loading: Promise<void> | undefined
+  const load = () =>
+    (loading ??= (async () => {
+      await auto
+      await advance(2)
+    })())
+  let settled: Promise<void> | undefined
+  const settle = (task: () => Promise<void>) => (settled ??= task())
+  return {
+    loading: load,
+    finish: async () => {
+      await settle(async () => {
+        await load()
+        await waitForStage()
+        await transitionTo("success", completionHold)
+      })
+      const mode = await terminalMode
+      renderer.externalOutputMode = "passthrough"
+      renderer.screenMode = "alternate-screen"
+      renderer.consoleMode = "console-overlay"
+      renderer.requestRender()
+      await Promise.race([renderer.idle(), Bun.sleep(500)])
+      transferred = true
+      return {
+        renderer,
+        mode,
+        complete: () => setVisible(false),
+      }
+    },
+    fail: (message) =>
+      settle(async () => {
+        setFailure(message)
+        await transitionTo("failure", 250)
+        await close()
+      }),
+    close,
+  }
+}
+
+const colors = {
+  accent: RGBA.fromHex("#a6b8ff"),
+  accentBright: RGBA.fromHex("#eef1ff"),
+  accentDim: RGBA.fromHex("#596998"),
+  error: RGBA.fromHex("#ff8192"),
+  muted: RGBA.fromHex("#808080"),
+  success: RGBA.fromHex("#8bd5a5"),
+  text: RGBA.fromHex("#eeeeee"),
+}
+
+const monogram = go.right.slice(1)
+const sweepBlend = 8
+const textDim = RGBA.fromHex("#4c4c4c")
+const rampSteps = 32
+
+const blend = (from: RGBA, to: RGBA, amount: number) =>
+  RGBA.fromValues(
+    from.r + (to.r - from.r) * amount,
+    from.g + (to.g - from.g) * amount,
+    from.b + (to.b - from.b) * amount,
+  )
+const ramp = (from: RGBA, to: RGBA) =>
+  Array.from({ length: rampSteps + 1 }, (_, step) => blend(from, to, step / rampSteps))
+const railRamp = ramp(colors.accentDim, colors.accentBright)
+const monogramRamp = ramp(colors.muted, colors.accent)
+const rampCache = new Map<RGBA, ReadonlyArray<RGBA>>()
+const rampFor = (color: RGBA) => {
+  const cached = rampCache.get(color)
+  if (cached) return cached
+  const result = ramp(textDim, color)
+  rampCache.set(color, result)
+  return result
+}
+const shade = (palette: ReadonlyArray<RGBA>, brightness: number) =>
+  palette[Math.round(Math.max(0, Math.min(1, brightness)) * rampSteps)]
+
+type Cell = { readonly char: string; readonly color: RGBA; readonly bold?: boolean }
+const styled = (text: string, color: RGBA, bold?: boolean): Cell[] =>
+  Array.from(text).map((char) => ({ char, color, bold }))
+const phrase = (...segments: ReadonlyArray<readonly [string, RGBA, boolean?]>): Cell[] =>
+  segments.flatMap((segment, index) => [
+    ...(index > 0 ? styled(" ", colors.muted) : []),
+    ...styled(segment[0], segment[1], segment[2]),
+  ])
+
+function Monogram(props: { ink: () => RGBA }) {
+  const shadow = createMemo(() => {
+    const ink = props.ink()
+    return RGBA.fromValues(ink.r * 0.25, ink.g * 0.25, ink.b * 0.25)
+  })
+  return (
+    <box flexDirection="column">
+      <For each={monogram}>
+        {(line) => (
+          <box flexDirection="row">
+            <For each={Array.from(line)}>
+              {(char) =>
+                char === "_" ? (
+                  <text bg={shadow()} selectable={false}>
+                    {" "}
+                  </text>
+                ) : (
+                  <text fg={props.ink()} selectable={false}>
+                    {char}
+                  </text>
+                )
+              }
+            </For>
+          </box>
+        )}
+      </For>
+    </box>
+  )
+}
+
+type CellTransition = { from: Cell[]; to: Cell[]; done?: () => void }
+
+function createTransition(render: (transition: CellTransition, progress: number) => Cell[]) {
+  const [state, setState] = createSignal<{ from: Cell[]; to: Cell[]; done?: () => void } | undefined>()
+  const [progress, setProgress] = createSignal(0)
+  let elapsed = 0
+  const cells = createMemo(() => {
+    const transition = state()
+    if (!transition) return undefined
+    return render(transition, progress())
+  })
+  return {
+    start(from: Cell[], to: Cell[], done?: () => void) {
+      elapsed = 0
+      setProgress(0)
+      setState({ from, to, done })
+    },
+    tick(deltaTime: number) {
+      const transition = state()
+      if (!transition) return
+      elapsed = Math.min(transitionDuration, elapsed + deltaTime)
+      setProgress(elapsed / transitionDuration)
+      if (elapsed < transitionDuration) return
+      setState(undefined)
+      transition.done?.()
+    },
+    cells,
+    progress,
+  }
+}
+
+const createSweep = () =>
+  createTransition((transition, progress) => {
+    const length = Math.max(transition.from.length, transition.to.length)
+    const front = smoothstep(progress) * (length + 2 * sweepBlend) - sweepBlend
+    return Array.from({ length }, (_, index) => {
+      const passed = Math.max(0, Math.min(1, (front - index) / sweepBlend))
+      const brightness = smoothstep(Math.abs(passed * 2 - 1))
+      const cell = (passed >= 0.5 ? transition.to[index] : transition.from[index]) ?? {
+        char: " ",
+        color: colors.text,
+      }
+      return { ...cell, color: shade(rampFor(cell.color), brightness) }
+    })
+  })
+
+const createFade = () =>
+  createTransition((transition, progress) => {
+    const entering = progress >= 0.5
+    const brightness = smoothstep(entering ? progress * 2 - 1 : 1 - progress * 2)
+    return (entering ? transition.to : transition.from).map((cell) => ({
+      ...cell,
+      color: shade(rampFor(cell.color), brightness),
+    }))
+  })
+
+const smoothstep = (value: number) => value * value * (3 - 2 * value)
+const frameDone = Promise.resolve()
+
+function UpdateFooter(props: {
+  from?: string
+  active: () => number
+  outcome: () => "running" | "success" | "failure"
+  failure: () => string
+  animating: () => boolean
+  renderer: CliRenderer
+  onOutcomeSettled: () => void
+}) {
+  const term = useTerminalDimensions()
+  const [position, setPosition] = createSignal(0)
+  const [pulse, setPulse] = createSignal(0)
+  const headerFade = createFade()
+  const statusSweep = createSweep()
+  const runningHeader = () =>
+    phrase(
+      ["OpenCode", colors.muted, true],
+      ["is updating", colors.muted],
+      ...(props.from
+        ? ([
+            ["from", colors.muted],
+            [props.from, colors.accentDim],
+          ] as const)
+        : []),
+      ["to", colors.muted],
+      [InstallationVersion, colors.accent],
+    )
+  const completedHeader = phrase(
+    ["OpenCode", colors.muted, true],
+    ["updated to", colors.muted],
+    [InstallationVersion, colors.accent],
+  )
+  const pausedHeader = phrase(["OpenCode", colors.muted, true], ["update paused", colors.muted])
+  const outcomeStatus = () =>
+    props.outcome() === "success"
+      ? [...styled("✓", colors.success), ...styled(" Ready", colors.text)]
+      : [...styled("!", colors.error), ...styled(" " + props.failure(), colors.text)]
+  let previousStage: string = stages[0]
+  createEffect(
+    on(props.active, (index) => {
+      if (props.outcome() !== "running") return
+      const next = stages[index]
+      if (next === previousStage) return
+      statusSweep.start(styled(previousStage, colors.text), styled(next, colors.text))
+      previousStage = next
+    }),
+  )
+  createEffect(
+    on(
+      props.outcome,
+      (outcome) => {
+        if (outcome === "running") return
+        const visibleStatus = untrack(statusSweep.cells) ?? styled(previousStage, colors.text)
+        headerFade.start(runningHeader(), outcome === "success" ? completedHeader : pausedHeader)
+        statusSweep.start([...styled("  ", colors.text), ...visibleStatus], outcomeStatus(), props.onOutcomeSettled)
+      },
+      { defer: true },
+    ),
+  )
+  const header = createMemo(
+    () =>
+      headerFade.cells() ??
+      (props.outcome() === "success"
+        ? completedHeader
+        : props.outcome() === "failure"
+          ? pausedHeader
+          : runningHeader()),
+  )
+  const monogramInk = createMemo(() =>
+    props.outcome() === "success" ? shade(monogramRamp, smoothstep(headerFade.progress())) : colors.muted,
+  )
+  const rail = createMemo(() => {
+    const width = Math.max(0, Math.min(30, term().width - 39))
+    if (width === 0) return []
+    const filled = Math.round(position() * width)
+    const glowRadius = 6
+    const span = Math.max(1, filled + glowRadius * 2)
+    const center = pulse() * span - glowRadius
+    const success = props.outcome() === "success"
+    const completion = smoothstep(headerFade.progress())
+    return Array.from({ length: width }, (_, index) => {
+      const color =
+        index >= filled
+          ? colors.muted
+          : shade(railRamp, Math.max(0, 1 - Math.abs(index - center) / glowRadius) ** 2)
+      return {
+        char: success || index < filled ? "━" : "·",
+        color: success ? blend(color, colors.accent, completion) : color,
+      }
+    })
+  })
+
+  onMount(() => {
+    let value = 0
+    let velocity = 0
+    let phase = 0
+    const frame = (deltaTime: number) => {
+      if (!props.animating()) return frameDone
+      const elapsed = Math.min(0.032, deltaTime / 1_000)
+      const stiffness = 110
+      const damping = 2 * Math.sqrt(stiffness)
+      const target = props.outcome() === "success" ? 1 : (props.active() + 1) / stages.length
+      velocity += (stiffness * (target - value) - damping * velocity) * elapsed
+      value += velocity * elapsed
+      phase = (phase + deltaTime / 900) % 1
+      batch(() => {
+        setPosition(Math.max(0, Math.min(1, value)))
+        setPulse(phase)
+      })
+      headerFade.tick(deltaTime)
+      statusSweep.tick(deltaTime)
+      return frameDone
+    }
+    props.renderer.setFrameCallback(frame)
+    onCleanup(() => props.renderer.removeFrameCallback(frame))
+  })
+
+  return (
+    <box width="100%" height={4} flexDirection="row" gap={1} live={props.animating()}>
+      <Monogram ink={monogramInk} />
+      <box flexDirection="column" flexGrow={1} overflow="hidden">
+        <CellLine cells={header()} />
+        <Show
+          when={props.outcome() === "running"}
+          fallback={<CellLine cells={statusSweep.cells() ?? outcomeStatus()} />}
+        >
+          <box flexDirection="row" gap={1}>
+            <spinner frames={SPINNER_FRAMES} interval={80} color={colors.accent} />
+            <CellLine cells={statusSweep.cells() ?? styled(stages[props.active()], colors.text)} />
+          </box>
+        </Show>
+        <box flexDirection="row" gap={1}>
+          <CellLine cells={rail()} />
+          <text fg={colors.muted}>
+            {props.outcome() === "success" ? stages.length : props.active() + 1}/{stages.length}
+          </text>
+        </box>
+      </box>
+    </box>
+  )
+}
+
+function CellLine(props: { cells: ReadonlyArray<Cell> }) {
+  return (
+    <text truncate>
+      <Index each={props.cells}>
+        {(cell) => (
+          <span
+            style={{
+              fg: cell().color,
+              attributes: cell().bold ? TextAttributes.BOLD : TextAttributes.NONE,
+            }}
+          >
+            {cell().char}
+          </span>
+        )}
+      </Index>
+    </text>
+  )
+}
+
+export * as UpdatePreflight from "./update-preflight"

packages/cli/src/tui-config.ts

@@ -0,0 +1,24 @@
+export * as TuiConfig from "./tui-config"
+
+import { Global } from "@opencode-ai/core/global"
+import { TuiConfig } from "@opencode-ai/tui/config/v1"
+import { Effect, FileSystem, Option, Schema } from "effect"
+import { parse, type ParseError } from "jsonc-parser"
+import path from "path"
+
+export const load = Effect.fn("TuiConfig.load")(function* () {
+  const fs = yield* FileSystem.FileSystem
+  const global = yield* Global.Service
+  const filepath = path.join(global.config, "tui.json")
+  const text = yield* fs.readFileString(filepath).pipe(Effect.catch(() => Effect.succeed(undefined)))
+  if (!text) return TuiConfig.resolve({}, { terminalSuspend: process.platform !== "win32" })
+
+  const errors: ParseError[] = []
+  const input: unknown = parse(text, errors, { allowTrailingComma: true })
+  if (errors.length) return TuiConfig.resolve({}, { terminalSuspend: process.platform !== "win32" })
+
+  return TuiConfig.resolve(
+    Option.getOrElse(Schema.decodeUnknownOption(TuiConfig.Info)(input), () => ({})),
+    { terminalSuspend: process.platform !== "win32" },
+  )
+})

packages/cli/test/footer-keymap.test.tsx

@@ -0,0 +1,106 @@
+/** @jsxImportSource @opentui/solid */
+import { createDefaultOpenTuiKeymap } from "@opentui/keymap/opentui"
+import { testRender, useRenderer } from "@opentui/solid"
+import { OpencodeKeymapProvider, registerOpencodeKeymap } from "@opencode-ai/tui/keymap"
+import { resolve } from "@opencode-ai/tui/config/v1"
+import { expect, test } from "bun:test"
+import { createComponent, createSignal } from "solid-js"
+import { RunFooterView } from "../src/mini/footer.view"
+import { RUN_THEME_FALLBACK } from "../src/mini/theme"
+import type { FooterState, FooterSubagentState, FooterView } from "../src/mini/types"
+
+test("down opens subagents from an empty prompt", async () => {
+  const [state] = createSignal<FooterState>({
+    phase: "idle",
+    status: "",
+    queue: 0,
+    model: "gpt-5",
+    duration: "",
+    usage: "",
+    first: false,
+    interrupt: 0,
+    exit: 0,
+  })
+  const [view] = createSignal<FooterView>({ type: "prompt" })
+  const [subagents] = createSignal<FooterSubagentState>({
+    tabs: [
+      {
+        sessionID: "subagent-1",
+        partID: "part-1",
+        callID: "call-1",
+        label: "Explore",
+        description: "Inspect the keymap",
+        status: "running",
+        lastUpdatedAt: 1,
+      },
+    ],
+    details: {},
+    permissions: [],
+    questions: [],
+  })
+  const config = resolve(
+    { keybinds: { editor_open: "none", session_queued_prompts: "none" } },
+    { terminalSuspend: true },
+  )
+  let offKeymap: (() => void) | undefined
+
+  function Harness() {
+    const renderer = useRenderer()
+    const keymap = createDefaultOpenTuiKeymap(renderer)
+    offKeymap = registerOpencodeKeymap(keymap, renderer, config)
+
+    return createComponent(OpencodeKeymapProvider, {
+      keymap,
+      get children() {
+        return (
+          <RunFooterView
+            directory="/tmp"
+            findFiles={async () => []}
+            agents={() => []}
+            references={() => []}
+            commands={() => []}
+            providers={() => undefined}
+            currentModel={() => undefined}
+            variants={() => []}
+            currentVariant={() => undefined}
+            state={state}
+            view={view}
+            subagent={subagents}
+            theme={() => RUN_THEME_FALLBACK}
+            tuiConfig={config}
+            agent="opencode"
+            onSubmit={() => true}
+            onPermissionReply={() => {}}
+            onQuestionReply={() => {}}
+            onQuestionReject={() => {}}
+            onCycle={() => {}}
+            onInterrupt={() => false}
+            onEditorOpen={async () => undefined}
+            onInputClear={() => {}}
+            onExit={() => {}}
+            onModelSelect={() => {}}
+            onVariantSelect={() => {}}
+            onRows={() => {}}
+            onLayout={() => {}}
+            onStatus={() => {}}
+            onQueuedRemove={async () => true}
+          />
+        )
+      },
+    })
+  }
+
+  const app = await testRender(() => <Harness />, { width: 100, height: 8, kittyKeyboard: true })
+  try {
+    await app.renderOnce()
+    expect(app.renderer.currentFocusedEditor?.plainText).toBe("")
+    app.mockInput.pressArrow("down")
+    await app.renderOnce()
+    expect(app.captureCharFrame()).toContain("Select subagent")
+  } finally {
+    app.renderer.currentFocusedRenderable?.blur()
+    app.renderer.currentFocusedEditor?.blur()
+    offKeymap?.()
+    app.renderer.destroy()
+  }
+})

packages/cli/test/tui-config.test.ts

@@ -0,0 +1,25 @@
+import { NodeFileSystem } from "@effect/platform-node"
+import { Global } from "@opencode-ai/core/global"
+import { Effect } from "effect"
+import { expect, test } from "bun:test"
+import path from "path"
+import { TuiConfig } from "../src/tui-config"
+
+test("loads the global tui config", async () => {
+  const directory = await Bun.$`mktemp -d`.text().then((value) => value.trim())
+  await Bun.write(path.join(directory, "tui.json"), JSON.stringify({ keybinds: { leader: "ctrl+o" } }))
+
+  try {
+    const config = await Effect.runPromise(
+      TuiConfig.load().pipe(
+        Effect.provide(Global.layerWith({ config: directory })),
+        Effect.provide(NodeFileSystem.layer),
+      ),
+    )
+
+    expect(config.keybinds.get("leader")?.[0]?.key).toBe("ctrl+o")
+    expect(config.keybinds.get("session.new")?.[0]?.key).toBe("<leader>n")
+  } finally {
+    await Bun.$`rm -rf ${directory}`
+  }
+})

packages/client/src/effect/api/api.ts

@@ -476,18 +476,16 @@ export interface IntegrationApi<E = never> {
 type Endpoint11_0Request = Parameters<RawClient["server.mcp"]["mcp.list"]>[0]
 export type Endpoint11_0Input = { readonly location?: Endpoint11_0Request["query"]["location"] }
 export type Endpoint11_0Output = EffectValue<ReturnType<RawClient["server.mcp"]["mcp.list"]>>
-export type ServerMcpListOperation<E = never> = (input?: Endpoint11_0Input) => Effect.Effect<Endpoint11_0Output, E>
+export type McpListOperation<E = never> = (input?: Endpoint11_0Input) => Effect.Effect<Endpoint11_0Output, E>
 
 type Endpoint11_1Request = Parameters<RawClient["server.mcp"]["mcp.resource.catalog"]>[0]
 export type Endpoint11_1Input = { readonly location?: Endpoint11_1Request["query"]["location"] }
 export type Endpoint11_1Output = EffectValue<ReturnType<RawClient["server.mcp"]["mcp.resource.catalog"]>>
-export type ServerMcpResourceCatalogOperation<E = never> = (
-  input?: Endpoint11_1Input,
-) => Effect.Effect<Endpoint11_1Output, E>
+export type McpResourceCatalogOperation<E = never> = (input?: Endpoint11_1Input) => Effect.Effect<Endpoint11_1Output, E>
 
-export interface ServerMcpApi<E = never> {
-  readonly list: ServerMcpListOperation<E>
-  readonly resource: { readonly catalog: ServerMcpResourceCatalogOperation<E> }
+export interface McpApi<E = never> {
+  readonly list: McpListOperation<E>
+  readonly resource: { readonly catalog: McpResourceCatalogOperation<E> }
 }
 
 type Endpoint12_0Request = Parameters<RawClient["server.credential"]["credential.update"]>[0]
@@ -955,7 +953,7 @@ export interface AppApi<E = never> {
   readonly generate: GenerateApi<E>
   readonly provider: ProviderApi<E>
   readonly integration: IntegrationApi<E>
-  readonly "server.mcp": ServerMcpApi<E>
+  readonly mcp: McpApi<E>
   readonly credential: CredentialApi<E>
   readonly project: ProjectApi<E>
   readonly form: FormApi<E>

packages/client/src/effect/generated/client.ts

@@ -1134,7 +1134,7 @@ const adaptClient = (raw: RawClient) => ({
   generate: adaptGroup8(raw["server.generate"]),
   provider: adaptGroup9(raw["server.provider"]),
   integration: adaptGroup10(raw["server.integration"]),
-  "server.mcp": adaptGroup11(raw["server.mcp"]),
+  mcp: adaptGroup11(raw["server.mcp"]),
   credential: adaptGroup12(raw["server.credential"]),
   project: adaptGroup13(raw["server.project"]),
   form: adaptGroup14(raw["server.form"]),

packages/client/src/effect/service.ts

@@ -32,6 +32,15 @@ export type Options = {
   readonly command?: ReadonlyArray<string>
 }
 
+export type StartReason = "missing" | "version-mismatch"
+
+export type StartOptions = Options & {
+  // Called once when start() decides it must spawn: either no service was
+  // found, or a healthy service with a different version is being replaced.
+  // `existing` carries the registration of the service being replaced.
+  readonly onStart?: (reason: StartReason, existing?: Info) => void
+}
+
 // Read-only lookup: registration file plus health check and version gate.
 // Never spawns; escalation to start() is the caller's policy.
 export const discover = Effect.fn("service.discover")(function* (options: Options = {}) {
@@ -47,10 +56,13 @@ const discoverLocal = Effect.fnUntraced(function* (options: Options) {
 
 // Idempotent ensure-running: reuses a healthy compatible server, replaces a
 // version-mismatched one, and otherwise spawns the service command detached.
-export const start = Effect.fn("service.start")(function* (options: Options = {}) {
+export const start = Effect.fn("service.start")(function* (options: StartOptions = {}) {
   const compatible = yield* discover(options)
   if (compatible !== undefined) return compatible
   const mismatched = yield* find(options)
+  yield* Effect.sync(() =>
+    options.onStart?.(mismatched === undefined ? "missing" : "version-mismatch", mismatched?.info),
+  )
   if (mismatched !== undefined) yield* kill(mismatched.info, options).pipe(Effect.ignore)
 
   const [command, ...args] = options.command ?? ["opencode", "serve", "--service"]

packages/client/src/promise/api.ts

@@ -1,43 +1,15 @@
-import type {
-  AgentApi as EffectAgentApi,
-  CommandApi as EffectCommandApi,
-  EventApi as EffectEventApi,
-  IntegrationApi as EffectIntegrationApi,
-  ModelApi as EffectModelApi,
-  PluginApi as EffectPluginApi,
-  ProviderApi as EffectProviderApi,
-  ReferenceApi as EffectReferenceApi,
-  SessionApi as EffectSessionApi,
-  SkillApi as EffectSkillApi,
-} from "../effect/api/api.js"
-import type { Effect, Stream } from "effect"
+type Client = ReturnType<typeof import("./generated/client.js").make>
 
-type PromisifyOperation<Operation> = Operation extends (
-  ...args: infer Args
-) => Effect.Effect<infer Success, unknown, unknown>
-  ? (...args: Args) => Promise<Success>
-  : Operation extends (...args: infer Args) => Stream.Stream<infer Success, unknown, unknown>
-    ? (...args: Args) => AsyncIterable<Success>
-    : Operation extends (...args: infer _Args) => unknown
-      ? Operation
-      : Operation extends object
-        ? PromisifyApi<Operation>
-        : Operation
-
-type PromisifyApi<Api> = {
-  readonly [Name in keyof Api]: PromisifyOperation<Api[Name]>
-}
-
-export type AgentApi = PromisifyApi<EffectAgentApi<unknown>>
-export type CommandApi = PromisifyApi<EffectCommandApi<unknown>>
-export type EventApi = PromisifyApi<EffectEventApi<unknown>>
-export type IntegrationApi = PromisifyApi<EffectIntegrationApi<unknown>>
-export type ModelApi = PromisifyApi<EffectModelApi<unknown>>
-export type PluginApi = PromisifyApi<EffectPluginApi<unknown>>
-export type ProviderApi = PromisifyApi<EffectProviderApi<unknown>>
-export type ReferenceApi = PromisifyApi<EffectReferenceApi<unknown>>
-export type SessionApi = PromisifyApi<EffectSessionApi<unknown>>
-export type SkillApi = PromisifyApi<EffectSkillApi<unknown>>
+export type AgentApi = Client["agent"]
+export type CommandApi = Client["command"]
+export type EventApi = Client["event"]
+export type IntegrationApi = Client["integration"]
+export type ModelApi = Client["model"]
+export type PluginApi = Client["plugin"]
+export type ProviderApi = Client["provider"]
+export type ReferenceApi = Client["reference"]
+export type SessionApi = Client["session"]
+export type SkillApi = Client["skill"]
 
 export interface CatalogApi {
   readonly provider: ProviderApi

packages/client/src/promise/generated/client-error.ts

@@ -1,4 +1,9 @@
-export type ClientErrorReason = "Transport" | "UnexpectedStatus" | "UnsupportedContentType" | "MalformedResponse"
+export type ClientErrorReason =
+  | "Transport"
+  | "UnexpectedStatus"
+  | "UnsupportedContentType"
+  | "MalformedResponse"
+  | "SseEventTooLarge"
 
 export class ClientError extends Error {
   override readonly name = "ClientError"

packages/client/src/promise/generated/client.ts

@@ -90,10 +90,10 @@ import type {
   IntegrationAttemptCompleteOutput,
   IntegrationAttemptCancelInput,
   IntegrationAttemptCancelOutput,
-  ServerMcpListInput,
-  ServerMcpListOutput,
-  ServerMcpResourceCatalogInput,
-  ServerMcpResourceCatalogOutput,
+  McpListInput,
+  McpListOutput,
+  McpResourceCatalogInput,
+  McpResourceCatalogOutput,
   CredentialUpdateInput,
   CredentialUpdateOutput,
   CredentialRemoveInput,
@@ -193,12 +193,12 @@ import { ClientError } from "./client-error"
 export interface ClientOptions {
   readonly baseUrl: string
   readonly fetch?: typeof globalThis.fetch
-  readonly headers?: HeadersInit
+  readonly headers?: RequestInit["headers"]
 }
 
 export interface RequestOptions {
   readonly signal?: AbortSignal
-  readonly headers?: HeadersInit
+  readonly headers?: RequestInit["headers"]
 }
 
 interface RequestDescriptor {
@@ -213,6 +213,8 @@ interface RequestDescriptor {
   readonly binary?: true
 }
 
+const maxSseEventBytes = 16 * 1024 * 1024
+
 export function make(options: ClientOptions) {
   const fetch = options.fetch ?? globalThis.fetch
 
@@ -289,7 +291,7 @@ export function make(options: ClientOptions) {
             throw new ClientError("Transport", { cause })
           }
           buffer += decoder.decode(next.value, { stream: !next.done })
-          if (buffer.length > 1_048_576) throw new ClientError("MalformedResponse")
+          if (buffer.length > maxSseEventBytes) throw new ClientError("SseEventTooLarge")
           const trailingCarriageReturn = !next.done && buffer.endsWith("\r")
           if (trailingCarriageReturn) buffer = buffer.slice(0, -1)
           buffer = buffer.replaceAll("\r\n", "\n").replaceAll("\r", "\n")
@@ -701,7 +703,7 @@ export function make(options: ClientOptions) {
                 path: `/api/session/${encodeURIComponent(input.sessionID)}/instructions/entries/${encodeURIComponent(input.key)}`,
                 body: { value: input["value"] },
                 successStatus: 204,
-                declaredStatuses: [404, 400, 401],
+                declaredStatuses: [404, 413, 400, 401],
                 empty: true,
               },
               requestOptions,
@@ -939,9 +941,9 @@ export function make(options: ClientOptions) {
           ),
       },
     },
-    "server.mcp": {
-      list: (input?: ServerMcpListInput, requestOptions?: RequestOptions) =>
-        request<ServerMcpListOutput>(
+    mcp: {
+      list: (input?: McpListInput, requestOptions?: RequestOptions) =>
+        request<McpListOutput>(
           {
             method: "GET",
             path: `/api/mcp`,
@@ -953,8 +955,8 @@ export function make(options: ClientOptions) {
           requestOptions,
         ),
       resource: {
-        catalog: (input?: ServerMcpResourceCatalogInput, requestOptions?: RequestOptions) =>
-          request<ServerMcpResourceCatalogOutput>(
+        catalog: (input?: McpResourceCatalogInput, requestOptions?: RequestOptions) =>
+          request<McpResourceCatalogOutput>(
             {
               method: "GET",
               path: `/api/mcp/resource`,

packages/client/test/promise.test.ts

@@ -284,6 +284,43 @@ test("event.subscribe terminates on malformed Promise SSE data", async () => {
   })
 })
 
+test("event.subscribe accepts a fragmented SSE event below the size limit", async () => {
+  const event = { id: "evt_large", type: "test.large", data: { output: "x".repeat(12 * 1024 * 1024) } }
+  const encoded = new TextEncoder().encode(`data: ${JSON.stringify(event)}\n\n`)
+  const client = OpenCode.make({
+    baseUrl: "http://localhost:3000",
+    fetch: async () =>
+      new Response(
+        new ReadableStream({
+          start(controller) {
+            for (let offset = 0; offset < encoded.length; offset += 64 * 1024) {
+              controller.enqueue(encoded.slice(offset, offset + 64 * 1024))
+            }
+            controller.close()
+          },
+        }),
+        { headers: { "content-type": "text/event-stream" } },
+      ),
+  })
+
+  await expect(client.event.subscribe()[Symbol.asyncIterator]().next()).resolves.toEqual({ done: false, value: event })
+})
+
+test("event.subscribe rejects an SSE event above the size limit", async () => {
+  const client = OpenCode.make({
+    baseUrl: "http://localhost:3000",
+    fetch: async () =>
+      new Response(`data: ${JSON.stringify({ output: "x".repeat(16 * 1024 * 1024) })}`, {
+        headers: { "content-type": "text/event-stream" },
+      }),
+  })
+
+  await expect(client.event.subscribe()[Symbol.asyncIterator]().next()).rejects.toMatchObject({
+    name: "ClientError",
+    reason: "SseEventTooLarge",
+  })
+})
+
 test("session methods use the public HTTP contract", async () => {
   const requests: Array<{ url: string; init?: RequestInit }> = []
   const client = OpenCode.make({

packages/codemode/README.md

@@ -1,37 +1,40 @@
 # @opencode-ai/codemode
 
-Effect-native confined code execution over explicit, schema-described tools.
+This is our take on code mode. Programs are written in a lightweight, JavaScript-like DSL and run in the package's
+own interpreter. They never execute as actual JavaScript, so there is no runtime to escape into. The interpreter
+itself can reach nothing; every effect a program has goes through a tool you explicitly supplied. The tradeoff is a
+bounded language rather than full JavaScript: the [interpreter support checklist](./interpreter-support.md) documents
+exactly what is supported.
 
-CodeMode lets a model write a small JavaScript program that can call only the tools supplied by the host. The program can sequence calls, transform plain data, branch, loop, and run independent calls in parallel without receiving ambient filesystem, process, network, module, or application authority.
+[Cloudflare's post](https://blog.cloudflare.com/code-mode/) introduced the idea. Their implementation executes
+generated code in isolate sandboxes. We took a lighter route: a pure interpreter that runs wherever your application
+runs, no sandbox required.
 
-The package is currently private to this workspace. Its API is designed around one-shot and reusable execution:
+## How it differs from JavaScript
 
-```ts
-// One execution
-yield * CodeMode.execute({ tools, code })
+The deliberate differences:
 
-// A reusable runtime
-const runtime = CodeMode.make({ tools, limits })
-yield * runtime.execute(code)
-```
+- **No ambient authority.** No `fetch`, `process`, filesystem, timers, or host globals - only the allowlisted standard
+  library and the `tools` tree.
+- **No dynamic code.** No `eval`, `Function`, or module loading.
+- **Plain-data boundaries.** Tool arguments and program results are JSON-like data. Dates become ISO strings, RegExp,
+  Map, and Set serialize as `{}`, and promises, functions, and runtime references cannot cross the boundary.
+- **Eager, supervised promises.** Tool calls and async functions start immediately when called. Whatever is still
+  running when the program returns is interrupted - race losers and fire-and-forget calls alike - so a program must
+  await every call whose completion matters. Rejections that settle un-awaited become `warnings` on the result instead
+  of crashing the run.
+- **REPL-style results.** An omitted `return` yields the final top-level expression; `undefined` normalizes to `null`.
 
-## Install
-
-Within this workspace:
-
-```json
-{
-  "dependencies": {
-    "@opencode-ai/codemode": "workspace:*"
-  }
-}
-```
-
-Hosts interact with CodeMode through `effect` (tool `run` implementations, `Effect`-typed results), so they should depend on `effect` themselves.
+Beyond these, the language is a growing subset rather than a divergent one: unsupported syntax returns an
+`UnsupportedSyntax` diagnostic with a source location, and current gaps (for example thenable assimilation, classes,
+generators, and full sparse-array parity) are tracked as unchecked items in the
+[interpreter support checklist](./interpreter-support.md).
 
 ## Quick Start
 
-Define tools with Effect Schema, then place them in the object tree exposed to programs as `tools`:
+The package is workspace-private (`"@opencode-ai/codemode": "workspace:*"`). Hosts interact with it through `effect`
+and should depend on `effect` themselves. Define tools with Effect Schema, then place them in the object tree exposed
+to programs as `tools`:
 
 ```ts
 import { CodeMode, Tool } from "@opencode-ai/codemode"
@@ -60,69 +63,53 @@ const result =
 `)
 ```
 
-`result` is always a `CodeMode.Result`. Program, validation, limit, and tool failures are returned as diagnostics rather than failing the Effect. Host interruption remains interruption.
-
-Successful result values are JSON-safe data. An explicit `return` produces the program result; when it is omitted, the final executable top-level expression is returned as a model-friendly REPL convenience. Otherwise reaching the end produces `null`. Returned `undefined` and nested `undefined` values are normalized to `null` as well.
+`result` is always a `CodeMode.Result`. Program, validation, limit, and tool failures are returned as diagnostics
+rather than failing the Effect; host interruption remains interruption.
 
 ## API
 
 ### `Tool.make`
 
-```ts
-const tool = Tool.make({
-  description,
-  input, // Effect Schema (validating) or JSON Schema (render-only)
-  output, // optional; same choice
-  run,
-})
-```
+`input` and `output` each accept a validating Effect Schema or a render-only JSON Schema document. Effect Schema input
+is decoded before `run` is invoked; an Effect Schema `output` is decoded and copied before the program sees it. JSON
+Schemas only shape the model-visible signature. Without `output` the signature advertises `Promise<unknown>`.
+Descriptions and schemas are model-visible contract; keep authorization in `run`.
 
-`input` and `output` each accept a validating Effect Schema or a render-only JSON Schema document (the natural shape for adapter-provided tools whose schemas arrive as JSON Schema, e.g. MCP definitions). Effect Schema input is decoded before `run` is invoked, and `run` returns the encoded representation of an Effect Schema `output`, which CodeMode decodes and copies before exposing it to the program. JSON Schemas only shape the model-visible signature; values pass through unvalidated (they still cross the plain-data boundary).
+### `CodeMode.execute` and `CodeMode.make`
 
-`output` is optional. Without it the tool's signature advertises `Promise<unknown>` and the host result is exposed as-is.
-
-The description and schemas are part of the model-visible tool contract. Keep descriptions concrete and put authorization in `run` or in the service it calls.
-
-Public tool types are grouped under the same namespace: `Tool.Definition`, `Tool.Options`, `Tool.SchemaType`, and `Tool.JsonSchema`.
-
-### `CodeMode.execute`
-
-Use `CodeMode.execute` for a single execution:
+`CodeMode.execute({ ...options, code })` runs once and is equivalent to `CodeMode.make(options).execute(code)`. A
+runtime from `make` reuses the tool set and policy:
 
 ```ts
-const result =
-  yield *
-  CodeMode.execute({
-    tools: { orders: { lookup: lookupOrder } },
-    code: `return await tools.orders.lookup({ id: "order_42" })`,
-    limits: { maxToolCalls: 10 },
-    onToolCallStart: (call) => Effect.logDebug("CodeMode tool started", call),
-    onToolCallEnd: (call) => Effect.logDebug("CodeMode tool settled", call),
-  })
-```
-
-The Effect environment is inferred from the supplied tools. CodeMode does not erase service requirements introduced by tool implementations.
-
-### `CodeMode.make`
-
-Use `CodeMode.make` when the tool set and execution policy are reused:
-
-```ts
-const runtime = CodeMode.make({
-  tools: { orders: { lookup: lookupOrder } },
-  limits: { timeoutMs: 30_000 },
-})
+const runtime = CodeMode.make({ tools, limits: { timeoutMs: 30_000 } })
 
 runtime.catalog() // structured tool descriptions
 runtime.instructions() // model-facing syntax and tool guide
 runtime.execute(source) // CodeMode.Result
 ```
 
-`CodeMode.Input`, `CodeMode.Result`, `CodeMode.Success`, `CodeMode.Failure`, `CodeMode.Diagnostic`, and `CodeMode.DiagnosticKind` are both Effect schemas and their inferred TypeScript types. Hosts can combine `CodeMode.Input` and `CodeMode.Result` with `runtime.instructions()` and `runtime.execute()` when constructing a framework-specific agent tool.
+The Effect environment is inferred from the supplied tools; service requirements are not erased. Optional
+`onToolCallStart` / `onToolCallEnd` hooks observe admitted calls with decoded input, outcome, and duration; both are
+Effect-returning and must not fail.
 
-All other CodeMode types use the same namespace: `CodeMode.Options`, `CodeMode.ExecuteOptions`, `CodeMode.Runtime`, `CodeMode.ExecutionLimits`, `CodeMode.DiscoveryOptions`, `CodeMode.DataValue`, `CodeMode.ToolDescription`, and the `CodeMode.ToolCall*` observation types.
+### OpenAPI tools
 
-### Results
+`OpenAPI.fromSpec` turns an OpenAPI 3.x document into a tool subtree - one tool per operation, namespaced by dotted
+`operationId`:
+
+```ts
+const api = OpenAPI.fromSpec({ spec, auth: { resolve } })
+const runtime = CodeMode.make({ tools: { opencode: api.tools } })
+```
+
+It is synchronous and returns `{ tools, skipped }`: operations with unsupported encodings, non-JSON bodies, binary
+responses, or streaming land in `skipped` instead of producing broken tools. Auth is resolved host-side and never
+model-visible; generated tools require `HttpClient.HttpClient` in the environment. See the option docstrings in
+`src/openapi/types.ts` for full semantics.
+
+## Outputs
+
+Every execution returns a `CodeMode.Result`:
 
 ```ts
 type Result = Success | Failure
@@ -145,152 +132,11 @@ interface Failure {
 }
 ```
 
-`toolCalls` contains the names of calls admitted by the runtime in call order. It is retained on failure so hosts can audit partial execution without exposing inputs or host failures. A successful execution may also contain `warnings`: runtime-authored, non-fatal diagnostics alongside a valid value - unhandled rejections from promises that failed, un-awaited, before the program returned, or background work interrupted by the timeout after the program returned. Anything still running when the program returns is interrupted - race losers and fire-and-forget calls alike - so a program must await every call whose completion matters. Failure has an `error`; success may have `warnings`; program-authored console output stays in `logs`. Keeping the value on an unhandled rejection is a deliberate divergence from Node's crash-on-unhandled-rejection default: the computed value and the background failure are independently useful to the model, so the result carries both. When warnings are cut by `maxOutputBytes`, a final `Truncated` diagnostic marks the omission in-band, and `truncated` marks any result, warning, or log truncation (see Execution Limits).
+`value` is JSON-safe data. `warnings` are non-fatal diagnostics alongside a valid value (un-awaited rejections,
+timeout cleanup after the return). `logs` holds program console output, `truncated` marks any output-budget cut, and
+`toolCalls` lists admitted calls in order - retained on failure for auditing.
 
-### Tool-call hooks
-
-`onToolCallStart` receives `{ index, name, input }` after input decoding and before tool execution. The input is decoded host-side data and may include values produced by schema transformations; applications should avoid logging sensitive tool arguments indiscriminately.
-
-`onToolCallEnd` receives `{ index, name, input, durationMs, outcome, message? }` when an admitted call settles. `outcome` is `"success"` or `"failure"`; `message` is the model-safe failure message and is present only on failure. Interrupted calls (for example when the execution timeout fires) do not produce an end event. Both hooks are Effect-returning and must not fail.
-
-### OpenAPI tools
-
-`OpenAPI.fromSpec` turns an OpenAPI 3.x document into a tool subtree - one tool per operation. Dotted `operationId` values form namespaces such as `v2.session.get`. Missing IDs receive a flat method/path fallback such as `getUsersById`; names are sanitized and deduplicated. The host places the subtree under a key in its `tools` tree; that key is the model-visible namespace.
-
-```ts
-import { CodeMode, OpenAPI } from "@opencode-ai/codemode"
-import { Effect } from "effect"
-import { FetchHttpClient } from "effect/unstable/http"
-
-const api = OpenAPI.fromSpec({
-  spec: await Bun.file("openapi.json").json(), // parsed document (no YAML)
-  auth: {
-    resolve: ({ name, scopes, operation }) =>
-      name === "BearerAuth" ? Effect.succeed({ type: "bearer", token }) : Effect.succeed(undefined),
-  },
-})
-
-const runtime = CodeMode.make({ tools: { opencode: api.tools } })
-const result = await Effect.runPromise(runtime.execute(code).pipe(Effect.provide(FetchHttpClient.layer)))
-```
-
-`fromSpec` is synchronous and returns `{ tools, skipped }`. The initial adapter supports query `form`/`deepObject`, path/header `simple`, JSON request bodies, JSON responses, and text responses; unsupported parameter encodings, non-JSON request bodies, binary responses, and streaming operations land in `skipped` instead of producing broken tools. Operation and path servers take precedence over document servers unless `baseUrl` explicitly overrides all of them. Tool inputs flatten path, query, header, and closed object-body fields into one model-facing object while retaining their HTTP locations internally. Cross-location name collisions receive a location prefix such as `path_id` and `query_id`; composed, nullable, dictionary, conditionally-required, and non-object JSON bodies remain under `body`. Auth is never model-visible. Responses are limited to 50 MiB, and non-2xx responses become safe tool failures carrying the status and a size-capped body summary. Deferred capabilities are tracked in `src/openapi/TODO.md`.
-
-Supported bearer, basic, header, and query authentication follows OpenAPI `security` semantics and is resolved host-side via `auth.resolve` - credential storage, OAuth flows, and token refresh never enter the compiler. Cookie authentication alternatives are discarded; an operation is skipped when it has no supported alternative. See the option docstrings in `src/openapi/types.ts` for the full semantics. Generated tools require `HttpClient.HttpClient` (from `effect/unstable/http`) in the Effect environment - provide `FetchHttpClient.layer` or a custom/test client layer at execution. The supplied client owns redirect policy; credentialed hosts should reject redirects or strip credentials when the origin changes.
-
-## Discovery
-
-The agent-tool instructions use a budgeted catalog. Every tool namespace is always listed with its tool count regardless of budget, and as many complete, JSDoc-annotated tool signatures (each with a one-line description) as fit an estimated-token budget are inlined. Schema field descriptions and tags are part of each signature's measured cost. Selection is round-robin across namespaces for fairness: in each round (namespaces alphabetical), every namespace still holding un-inlined tools attempts to place its next-cheapest signature against the shared budget, and a namespace whose next signature does not fit drops out while the others keep going - so every namespace gets some representation before any namespace gets everything. The instructions state exactly how comprehensive the list is, both overall (`COMPLETE list` vs `PARTIAL - N of M shown`) and per namespace (`(3 tools)`, `(3 tools, 1 shown)`, `(3 tools, none shown)`).
-
-The catalog-entry budget defaults to 2,000 estimated tokens (characters / 4, the same heuristic OpenCode uses). It applies only to full tool entries shown in the catalog; fixed instructions and namespace summaries are not counted. Override it when constructing a runtime:
-
-```ts
-const runtime = CodeMode.make({
-  tools,
-  discovery: { catalogBudget: 6_000 },
-})
-```
-
-The budget must be a non-negative safe integer.
-
-The runtime search tool is always registered - including when the catalog is fully inlined - so a speculative `tools.$codemode.search` call never fails as an unknown tool. It is only advertised in the instructions when the inlined list is partial:
-
-```ts
-const matches = await tools.$codemode.search({
-  query: "order status",
-  namespace: "orders", // optional: scope to one top-level namespace
-  limit: 10,
-  offset: 0,
-})
-```
-
-`search` performs deterministic, additive field-weighted matching. The query is tokenized (camelCase boundaries split; every non-alphanumeric character is a separator; empties and `*` are dropped), and each term scores every tool: exact path or path-segment match (20), path substring (8), description substring (4), and searchable-text substring (2). Each term also carries naive singular variants (trailing `s`/`es` stripped), and a field check passes when the term or any variant matches - so a plural query term (`issues`) still finds a tool whose text only says `issue`, without changing the weights. The searchable text also includes the input schema's property names and their description strings, so a query naming a parameter finds its tool, and substring matching means partial words match. Scores sum across terms; matches are sorted by score (ties broken alphabetically by path), then sliced from the zero-based `offset` (default 0) to the configured `limit` (default 10). `remaining` counts matches after the current page. `next` is `{ offset }` when another page exists and `null` on the final page; spread it into the original request to preserve its query, namespace, and limit.
-
-```ts
-const request = { query: "order status", namespace: "orders", limit: 10 }
-const page = await tools.$codemode.search(request)
-const nextPage = page.next ? await tools.$codemode.search({ ...request, ...page.next }) : undefined
-```
-
-Each result contains the path, description, and the same generated TypeScript signature used by the inline catalog, so no second lookup is needed. Signatures use the JSDoc-annotated multiline form: each described input/output field carries its schema `description` as a `/** ... */` comment, and constraints TypeScript cannot express ride along as tags (`@deprecated`, `@default`, `@format`, `@minItems`, `@maxItems`).
-
-```ts
-tools.github.list_issues(input: {
-  /** Repository owner */
-  owner: string,
-  /** Cursor from the previous response's pageInfo */
-  after?: string,
-  /**
-   * Results per page
-   * @default 30
-   */
-  perPage?: number,
-}): Promise<unknown>
-```
-
-Result paths are rendered as JavaScript expressions rooted at `tools` (`tools.orders.lookup`, or `tools.context7["resolve-library-id"]` for non-identifier segments), so each `path` is directly usable as the call site. An empty query browses the catalog alphabetically by path; combined with `namespace` (`{ query: "", namespace: "orders" }`) it lists everything in that namespace. A query that names one tool path exactly (canonical path, `tools.`-prefixed path, or rendered JavaScript expression) is treated as a lookup and returns that tool alone.
-
-The instructions are structured markdown, ordered so the workflow sits at the top and the catalog at the bottom: a `## Workflow` section with numbered steps (find a tool via search when the catalog is partial, or pick from the inlined list when it is complete; call the exact path as-is; return only the needed fields), a `## Rules` section holding only guidance the workflow does not already cover (only listed/search-result Code Mode tools and internal runtime tools exist inside `tools`; filter and aggregate collections in code; narrow `Promise<unknown>` results at runtime; run independent calls through `Promise.all`; enumerate `tools` with `Object.keys`/`for...in`; browse a namespace and paginate search results when search is advertised), a short `## Language` section that identifies the runtime as a restricted JavaScript orchestration language and names its major unavailable capabilities, and the budgeted `## Available tools` catalog. Example call forms use explicit `<namespace>.<tool>`/`<field>` placeholders - never a real or fabricated tool name.
-
-A host cannot define its own `$codemode` top-level namespace.
-
-## Supported Programs
-
-CodeMode executes a deliberately bounded JavaScript subset. See the
-[interpreter support checklist](./interpreter-support.md) for the complete, checkable language and standard-library
-matrix, known semantic gaps, and intentional exclusions.
-
-At a high level, it supports:
-
-- Plain data, property access and assignment, destructuring, functions, conditionals, loops, spread, optional chaining,
-  and structured error handling.
-- Allowlisted Array, String, Number, Object, Math, JSON, console, Date, RegExp, Map, Set, URL, and URLSearchParams APIs.
-- Eager supervised tool promises, direct `await`, and the supported `Promise` combinators for concurrent work.
-- Live standard-library values inside the sandbox and predictable JSON-like serialization at tool/result boundaries.
-- Actionable diagnostics for unsupported syntax, invalid data, tool failures, limits, and execution failures.
-
-It does not expose ambient host authority or arbitrary JavaScript execution. Unsupported syntax returns an
-`UnsupportedSyntax` diagnostic with a source location when available.
-
-CodeMode is an orchestration language, not a general JavaScript runtime.
-
-## Execution Limits
-
-The limits are exactly three knobs:
-
-| Limit            |              Default | Bounds                                               |
-| ---------------- | -------------------: | ---------------------------------------------------- |
-| `timeoutMs`      |    none - no timeout | Wall-clock execution time.                           |
-| `maxToolCalls`   |     none - unlimited | Tool calls admitted during the execution.            |
-| `maxOutputBytes` | none - no truncation | Retained result value and logs; warnings separately. |
-
-No limit has a default, on purpose: execution budgets are host policy, not library policy - a host that wants a bound sets one; a host that can interrupt the execution fiber (as OpenCode does on user cancel) may set no timeout, and a host with its own tool-output truncation (as OpenCode has) may leave `maxOutputBytes` unset. A host with neither should set `maxOutputBytes`, or oversized results silently flood model context.
-
-Pass only the overrides you need:
-
-```ts
-const runtime = CodeMode.make({
-  tools,
-  limits: {
-    maxToolCalls: 20,
-    timeoutMs: 60_000,
-  },
-})
-```
-
-Limits are safe integers. `timeoutMs` must be at least `1`; the others may be `0`. Invalid configuration throws a `RangeError` when `CodeMode.make` or `CodeMode.execute` is called. An explicitly `undefined` value is the same as leaving the limit unset.
-
-`maxOutputBytes` is a payload budget, not a strict byte cap on the final rendered tool message. It counts the serialized result value and retained log lines; warning diagnostics are bounded by a separate budget of the same size, so a large value never silences runtime diagnostics. Fixed truncation notices and framing added by a host when it renders the structured result are additional and may make the final message exceed the configured number.
-
-Exceeding a configured `maxOutputBytes` never fails the execution. An oversized result value is replaced by its truncated serialized text plus an explanatory marker, logs are kept within the remaining budget, warnings are kept within their own budget, omitted entries receive a summary marker, and the result carries `truncated: true`.
-
-When configured, the timeout interrupts in-flight tool Effects, including eagerly started calls the program has not awaited (their fibers are supervised by the execution). The interpreter yields cooperatively between steps, so the timeout also interrupts pure busy loops (`while (true) {}`) - no separate work budget exists. Tool implementations remain responsible for making their external operations interruptible or independently bounded: the timeout bounds when interruption begins, not when the result is delivered, which waits for tool interruption cleanup to finish. If the timeout fires after the program has already returned a valid value - while the runtime is interrupting leftover work and waiting for its cleanup - the result stays successful: the computed value is returned with a `TimeoutExceeded` warning instead of being discarded.
-
-Two interpreter internals are fixed constants rather than knobs: at most 8 tool calls run concurrently, and values crossing a data boundary may nest at most 32 levels deep (deeper values fail as `InvalidDataValue`, which reads better than a native stack-overflow error). Neither is part of the public contract.
-
-## Diagnostics
-
-Failures are data:
+Failure `error` and success `warnings` share one diagnostic vocabulary:
 
 | Kind                    | Meaning                                                                                                   |
 | ----------------------- | --------------------------------------------------------------------------------------------------------- |
@@ -306,58 +152,45 @@ Failures are data:
 | `ExecutionFailure`      | The program threw or another execution error occurred.                                                    |
 | `Truncated`             | Warning-only marker: additional warnings were omitted by `maxOutputBytes`.                                |
 
-Unknown host failures, defects, invalid outputs, and copying failures are sanitized. To return a safe operational refusal, fail with `toolError`:
+Unknown host failures, defects, and invalid outputs are sanitized. `toolError("safe message")` is the explicit channel
+for a model-visible refusal; its optional cause never crosses the boundary.
 
-```ts
-import { toolError } from "@opencode-ai/codemode"
+## Discovery
 
-run: ({ id }) => (authorized(id) ? loadOrder(id) : Effect.fail(toolError("Order is unavailable")))
-```
+The generated instructions inline a budgeted catalog (default 2,000 estimated tokens, override with
+`discovery: { catalogBudget }`): every namespace is always listed with its tool count, signatures are selected
+round-robin so every namespace gets representation, and the instructions state whether the list is complete or
+partial. Programs also get a global `search(...)` built-in - always available, advertised when the list is partial:
+synchronous, deterministic field-weighted substring matching that returns directly callable paths with full
+signatures, supports namespace scoping and pagination, and treats an empty query as browsing and an exact path as
+lookup. Search counts as an admitted tool call.
 
-Only the supplied message is model-visible. The optional cause is never returned in `CodeMode.Result`; hosts should perform any required internal logging before crossing this boundary.
+## Execution Limits
 
-## Authority Boundary
+| Limit            |              Default | Bounds                                               |
+| ---------------- | -------------------: | ---------------------------------------------------- |
+| `timeoutMs`      |    none - no timeout | Wall-clock execution time.                           |
+| `maxToolCalls`   |     none - unlimited | Tool calls admitted during the execution.            |
+| `maxOutputBytes` | none - no truncation | Retained result value and logs; warnings separately. |
 
-CodeMode confines programs to the supplied tool tree, but it does not decide what those tools may do.
+No limit has a default, on purpose: execution budgets are host policy. A host without its own truncation or
+interruption should set `maxOutputBytes` and `timeoutMs`. Limits are safe integers; invalid configuration throws a
+`RangeError` at construction. Exceeding `maxOutputBytes` never fails the execution - oversized output is truncated
+with an in-band marker. The timeout interrupts in-flight tool fibers and pure busy loops alike; a value the program
+already returned survives a cleanup timeout as a success with a `TimeoutExceeded` warning. Two internals are fixed
+constants, not knobs: at most 8 concurrent tool calls, and 32 levels of data nesting at boundaries.
 
-The host owns:
+## Boundaries and Non-Goals
 
-- Authentication and authorization.
-- Tool selection and immutable scope.
-- Credentials and network clients.
-- Persistence, idempotency, approval, and durable side effects.
-- Logging and redaction policy.
+The host owns authentication, authorization, tool selection, credentials, persistence, approval, and logging policy.
+CodeMode owns interpretation, schema and plain-data boundaries, resource limits, diagnostics, and discovery. A program
+can only exercise authority already present in the supplied tools - do not expose a broad tool and expect the prompt
+to restrict it.
 
-CodeMode owns:
-
-- Parsing and interpreting the supported subset without `eval`.
-- Schema boundaries around tool calls.
-- Plain-data copying and blocked prototype members.
-- Resource limits, call accounting, and normalized diagnostics.
-- Model-facing tool discovery and instructions.
-
-A program cannot gain authority through prose or generated code. It can only exercise authority already present in the supplied tools. Do not expose a broad tool and expect the prompt to restrict it.
-
-## Laws
-
-The public contract is guided by these equivalences:
-
-- `CodeMode.execute({ ...options, code })` is equivalent to `CodeMode.make(options).execute(code)`.
-- A tool implementation is not invoked unless its input has decoded successfully.
-- A tool result is not visible to the program unless its output has decoded and crossed the plain-data boundary successfully.
-- Unknown host failures do not become model-visible diagnostics; `ToolError` is the explicit safe-message channel.
-- Host interruption remains interruption rather than a `CodeMode.Failure`.
-
-## Non-Goals
-
-- Generic permission prompts or approval workflows.
-- Durable pause/resume, replay, or storage adapters.
-- Exactly-once external side effects.
-- Application authorization or product policy.
-- A filesystem or process sandbox for arbitrary JavaScript.
-- Compatibility with the full JavaScript language or npm ecosystem.
-
-Applications that need approval or durable consequences should model those above CodeMode and expose only the currently authorized tools.
+Non-goals: permission prompts and approval workflows, durable pause/resume or replay, exactly-once side effects,
+application authorization policy, sandboxing arbitrary JavaScript, and compatibility with the full language or npm
+ecosystem. Applications that need approval or durable consequences should model those above CodeMode and expose only
+the currently authorized tools.
 
 ## Testing
 
@@ -367,5 +200,3 @@ From the package directory:
 bun test
 bun run typecheck
 ```
-
-The direct suite covers public projections, discovery, schema boundaries, diagnostic sanitization, resource limits, tool-call observation, and interruption.

packages/codemode/codemode.md

@@ -32,7 +32,7 @@ CodeMode is an orchestration language, not a general JavaScript runtime or an ap
 The generic runtime lives in `packages/codemode` and is host-neutral:
 
 1. The host builds a tree of `Tool.make(...)` definitions and calls `CodeMode.make(...)` or `CodeMode.execute(...)`.
-2. CodeMode generates model instructions, a budgeted inline catalog, and the internal `$codemode.search` tool.
+2. CodeMode generates model instructions, a budgeted inline catalog, and the global `search(...)` built-in.
 3. TypeScript syntax is transpiled away, Acorn parses the resulting JavaScript, and an owned tree-walking interpreter
    executes it without `eval`.
 4. Tool inputs and outputs cross schema and plain-data boundaries before they become visible on either side.
@@ -46,13 +46,14 @@ advertised as `Promise<unknown>`.
 ### Discovery and model workflow
 
 The model sees a token-budgeted catalog. Every namespace remains visible, and complete signatures are selected
-round-robin across namespaces so one large namespace cannot starve the others. `$codemode.search` is always callable
-and is advertised when the inline catalog is partial.
+round-robin across namespaces so one large namespace cannot starve the others. The global `search(...)` built-in is
+always callable - synchronously, counted as an admitted tool call - and is advertised when the inline catalog is
+partial.
 
 The intended workflow is:
 
-1. Pick an exact signature from the inline catalog, or return `$codemode.search(...)` results and use a selected path
-   in the next execution.
+1. Pick an exact signature from the inline catalog, or return `search(...)` results and use a selected path in the
+   next execution.
 2. Call the exact returned path without guessing or normalizing segments.
 3. Narrow `Promise<unknown>` results before reading fields.
 4. Start independent calls together and await them with `Promise.all`.
@@ -64,10 +65,16 @@ path lookup, namespace browsing, deterministic ranking, and pagination.
 ### Tool execution
 
 Every sandbox promise starts eagerly on a run-once fiber owned by the whole CodeMode execution, including tool calls,
-async functions, `Promise.all`, `Promise.allSettled`, `Promise.race`, `Promise.resolve`, and `Promise.reject`. Nested
-functions therefore cannot end the lifetime of work they started. Independent aggregate batches overlap, and rejection
-is observed at the eventual `await`. `Promise.race` uses native non-cancelling settlement semantics: its first result
-wins while losers continue running. At normal completion CodeMode interrupts everything still running - race losers,
+async functions, chained `.then`/`.catch`/`.finally` reactions, `new Promise(executor)` constructions, and the
+`Promise.all`/`allSettled`/`race`/`any`/`resolve`/`reject` statics. Nested functions therefore cannot end the lifetime
+of work they started.
+Independent aggregate batches overlap, and rejection is observed at the eventual `await` or chained rejection handler.
+`Promise.race` and `Promise.any` use native non-cancelling settlement semantics: the deciding member wins while losers
+continue running, and an all-rejected `Promise.any` rejects with an `AggregateError`. `new Promise(...)` hands the
+executor first-class resolve/reject callables that may escape and settle the promise later, exactly once.
+Reaction ordering matches what V8 makes observable - handlers and await continuations are deferred and run in attach
+order, and a combinator settles one reaction turn after its deciding member - without promising exact microtask-count
+parity beyond that. At normal completion CodeMode interrupts everything still running - race losers,
 fail-fast `Promise.all` stragglers, and fire-and-forget calls alike: the program has returned, so no future await can
 exist, and work whose completion matters must be awaited by the program. Waiting for any class of leftover instead
 would let it hold the execution open, or deadlock it when queued work needs tool-call permits the leftovers occupy.

packages/codemode/interpreter-support.md

@@ -22,6 +22,8 @@ ultimate source of truth.
 - [x] JSON-like host boundaries with `undefined` and non-finite numbers normalized to `null`.
 - [x] Live Date, RegExp, Map, Set, URL, and URLSearchParams values inside the sandbox.
 - [x] Tool calls through the host-provided `tools` tree only.
+- [x] The global `search(...)` built-in: synchronous tool discovery that counts as an admitted tool call and is
+      shadowable by program declarations like other globals.
 - [x] Cooperative timeout, tool-call accounting, output bounding, and a maximum of eight concurrent tool calls.
 - [ ] Full JavaScript or TypeScript compatibility. CodeMode is a bounded orchestration language.
 
@@ -92,8 +94,9 @@ ultimate source of truth.
 - [x] Optional property access and optional calls.
 - [x] Function/tool calls and spread arguments.
 - [x] Sequence expressions (the comma operator).
-- [x] `await` for sandbox promises; awaiting a plain value is a no-op.
-- [x] `new` for Error types, Date, RegExp, Map, Set, URL, and URLSearchParams.
+- [x] `await` for sandbox promises; a plain value passes through unchanged, though every `await` still defers its
+      continuation one reaction turn.
+- [x] `new` for Error types, Date, RegExp, Map, Set, URL, URLSearchParams, and Promise.
 - [x] Arithmetic operators: `+`, `-`, `*`, `/`, `%`, and `**`.
 - [x] Equality and ordering: `==`, `!=`, `===`, `!==`, `<`, `<=`, `>`, and `>=`.
 - [x] Bitwise operators: `&`, `|`, `^`, `~`, `<<`, `>>`, and `>>>`.
@@ -102,27 +105,41 @@ ultimate source of truth.
 - [x] Prefix and postfix `++` and `--`.
 - [x] Plain, arithmetic, bitwise, and logical assignment operators.
 - [ ] Unary `void` and `delete`.
-- [ ] Arbitrary constructors and `new Promise(...)`.
+- [ ] Arbitrary constructors.
 
 ## Promises and tools
 
 - [x] Tool calls start eagerly and return supervised, run-once sandbox promises.
 - [x] Direct `await`, repeated awaits, and implicit resolution when a promise is returned from a function/program.
 - [x] `Promise.resolve` and `Promise.reject`.
-- [x] `Promise.all`, `Promise.allSettled`, and `Promise.race` over supported collections containing promises and plain
-      values.
+- [x] `Promise.all`, `Promise.allSettled`, `Promise.race`, and `Promise.any` over supported collections containing
+      promises and plain values.
 - [x] `Promise.all` preserves result order and rejects on the first observed failure without cancelling siblings.
 - [x] `Promise.allSettled` returns plain fulfilled/rejected outcome records.
 - [x] `Promise.race` settles from the first result without cancelling losers at settlement time.
 - [x] Real promise values from `Promise.all`, `Promise.allSettled`, and `Promise.race`; separately constructed
       combinator batches overlap as in normal JavaScript.
+- [x] Promise chaining with `.then`, `.catch`, and `.finally`: handlers run deferred in attach order, returned
+      promises are adopted, handler throws reject the derived promise, `.finally` preserves the original settlement
+      unless its cleanup fails, and direct self-resolution rejects with a `TypeError`.
+- [x] Every `await` (including of plain values and already-settled promises) defers its continuation one reaction
+      turn, so concurrent async functions interleave at await points as in JavaScript.
+- [x] Combinators settle one reaction turn after their deciding member (V8-observable ordering): reactions already
+      attached to members run first, and an aggregate cannot beat a plain value settling in the same turn into a
+      `Promise.race`. Exact microtask-count parity beyond this observable ordering is not a documented guarantee.
 - [x] All still-pending work (race losers, fail-fast `Promise.all` stragglers, and un-awaited calls alike) is
       interrupted when the program returns; rejections that settled un-awaited become `Success.warnings`
-      diagnostics.
+      diagnostics. A combinator abandoned inside its final settlement turn counts as pending and is interrupted
+      without a warning.
 - [x] `try`/`catch` can handle awaited tool and promise failures.
-- [ ] `Promise.any`.
-- [ ] Promise chaining with `.then`, `.catch`, and `.finally`.
-- [ ] Custom promise construction with `new Promise(...)`.
+- [x] `Promise.any`: first fulfillment wins; all-rejected rejects with an `AggregateError` whose `errors` array holds
+      the catch-normalized reasons in input order, and empty input rejects with an empty `AggregateError`.
+- [x] `new Promise((resolve, reject) => ...)`: the executor runs synchronously and receives first-class resolve/reject
+      callables that settle the promise exactly once (they may escape the executor and settle later); an executor
+      throw rejects unless the promise already settled, resolving with a promise adopts it, and resolving with the
+      promise itself rejects with a `TypeError`. Resolver callables work as `.then`/`.catch` handlers and collection
+      callbacks but remain opaque references that cannot cross the data boundary.
+- [ ] Thenable assimilation (objects with a `then` method are plain data, not promises).
 - [ ] Async iterables, host streams, and stream consumption.
 
 ## Objects and properties
@@ -153,7 +170,7 @@ ultimate source of truth.
 - [ ] The mapper and `thisArg` forms of `Array.from`.
 - [ ] `Array.prototype.toSpliced`.
 - [ ] Canonical index handling: a key such as `"01"` must not alias index `1`.
-- [ ] Complete sparse-array parity.
+- [ ] Complete sparse-array parity. Promise combinators do consume holes as `undefined` members, as in JS.
 - [ ] Correct `findLast` return behavior when its predicate mutates the examined element.
 
 ## Strings
@@ -258,6 +275,8 @@ ultimate source of truth.
 
 - [x] `Error`, `TypeError`, `RangeError`, `SyntaxError`, `ReferenceError`, `EvalError`, and `URIError`, callable with
       or without `new`.
+- [x] `AggregateError` with the `(errors, message?)` signature and an own `errors` array, constructed directly or by
+      an all-rejected `Promise.any`.
 - [x] Error `name`/`message`, error inheritance through `instanceof`, and plain-data serialization.
 - [x] `instanceof` for Date, RegExp, Map, Set, URL, URLSearchParams, Array, Object, Promise, and Error types.
 - [x] Catchable interpreter failures and awaited tool failures.

packages/codemode/src/codemode.ts

@@ -1,11 +1,6 @@
 import { Effect, Schema } from "effect"
 import { executeWithLimits } from "./interpreter/runtime.js"
-import {
-  type HostTools,
-  type Services,
-  type ToolDescription,
-  ToolRuntime,
-} from "./tool-runtime.js"
+import { type HostTools, type Services, type ToolDescription, ToolRuntime } from "./tool-runtime.js"
 import type { Definition } from "./tool.js"
 
 /** A tool call admitted during an execution. */
@@ -130,11 +125,7 @@ export type Runtime<R = never> = {
   readonly execute: (code: string) => Effect.Effect<Result, never, R>
 }
 
-const validateLimit = <Value extends number | undefined>(
-  name: keyof ExecutionLimits,
-  value: Value,
-  minimum: number,
-): Value => {
+const validateLimit = (name: keyof ExecutionLimits, value: number | undefined, minimum: number): number | undefined => {
   if (value !== undefined && (!Number.isSafeInteger(value) || value < minimum)) {
     throw new RangeError(`${name} must be a safe integer greater than or equal to ${minimum}.`)
   }
@@ -152,7 +143,6 @@ export const execute = <const Tools extends Record<string, unknown>>(
   options: ExecuteOptions<Tools>,
 ): Effect.Effect<Result, never, Services<Tools>> => {
   const tools = (options.tools ?? {}) as HostTools<Services<Tools>>
-  ToolRuntime.assertValidTools(tools)
   return executeWithLimits(options, resolveExecutionLimits(options.limits), ToolRuntime.searchIndex(tools))
 }
 
@@ -161,7 +151,6 @@ export const make = <const Tools extends Record<string, unknown> = {}>(
   options: Options<Tools> = {} as Options<Tools>,
 ): Runtime<Services<Tools>> => {
   const tools = (options.tools ?? {}) as HostTools<Services<Tools>>
-  ToolRuntime.assertValidTools(tools)
   const limits = resolveExecutionLimits(options.limits)
   const prepared = ToolRuntime.prepare(tools, options.discovery?.catalogBudget)
 

packages/codemode/src/interpreter/model.ts

@@ -1,5 +1,5 @@
 import type { SafeObject } from "../tool-runtime.js"
-import type { SandboxURL } from "../values.js"
+import type { SandboxPromise, SandboxURL } from "../values.js"
 
 export type SourcePosition = {
   line: number
@@ -61,12 +61,27 @@ export class ComputedValue {
 
 export class PromiseNamespace {}
 
-export type PromiseMethodName = "all" | "allSettled" | "race" | "resolve" | "reject"
+export type PromiseMethodName = "all" | "allSettled" | "race" | "any" | "resolve" | "reject"
 
 export class PromiseMethodReference {
   constructor(readonly name: PromiseMethodName) {}
 }
 
+export type PromiseInstanceMethodName = "then" | "catch" | "finally"
+
+export class PromiseInstanceMethodReference {
+  constructor(
+    readonly promise: SandboxPromise,
+    readonly name: PromiseInstanceMethodName,
+  ) {}
+}
+
+// The resolve/reject callables handed to a `new Promise(executor)` executor. `settle` closes
+// over the promise's deferred and is first-settlement-wins; later calls are no-ops, as in JS.
+export class PromiseCapabilityFunction {
+  constructor(readonly settle: (value: unknown) => void) {}
+}
+
 export type GlobalNamespaceName =
   | "Object"
   | "Math"
@@ -99,6 +114,10 @@ export class UriFunction {
   constructor(readonly name: "encodeURI" | "encodeURIComponent" | "decodeURI" | "decodeURIComponent") {}
 }
 
+// The global `search` built-in: synchronous tool discovery that shares the tool admission
+// pipeline (budget, audit, hooks) without living in the `tools` tree.
+export class SearchFunction {}
+
 export class ProgramThrow {
   constructor(readonly value: unknown) {}
 }
@@ -122,11 +141,11 @@ export type DiagnosticKind =
 export const OptionalShortCircuit: unique symbol = Symbol("codemode.optional-short-circuit")
 
 export const supportedSyntaxMessage =
-  "Supported orchestration syntax: tools.* calls (they return promises - resolve them with await), data literals, destructuring, optional chaining, template literals, conditionals, switch, loops (incl. for...of and for...in over object/array/tools keys), arrow functions, spread, try/catch, array methods (map/filter/find/findIndex/some/every/reduce/flatMap/forEach/sort/slice/concat/indexOf/lastIndexOf/at/flat/reverse/includes/join), string methods (incl. match/matchAll/replace/split with regular expressions), Date/RegExp/Map/Set/URL/URLSearchParams, URI encoding helpers, Object/Math/JSON helpers, captured console.log/warn/error/dir/table, and Promise.all/allSettled/race/resolve/reject over arrays mixing promises and plain values for parallel tool calls (promise chaining with .then/.catch is not supported - use await with try/catch)."
+  "Supported orchestration syntax: tools.* calls (they return promises - resolve them with await), data literals, destructuring, optional chaining, template literals, conditionals, switch, loops (incl. for...of and for...in over object/array/tools keys), arrow functions, spread, try/catch, array methods (map/filter/find/findIndex/some/every/reduce/flatMap/forEach/sort/slice/concat/indexOf/lastIndexOf/at/flat/reverse/includes/join), string methods (incl. match/matchAll/replace/split with regular expressions), Date/RegExp/Map/Set/URL/URLSearchParams, URI encoding helpers, Object/Math/JSON helpers, captured console.log/warn/error/dir/table, Promise.all/allSettled/race/any/resolve/reject over arrays mixing promises and plain values for parallel tool calls, promise chaining with .then/.catch/.finally, and new Promise((resolve, reject) => ...) construction."
 
 export class InterpreterRuntimeError extends Error {
   readonly node?: AstNode
-  errorName: string = "Error"
+  errorName = "Error"
 
   constructor(
     message: string,

packages/codemode/src/interpreter/runtime.ts

@@ -1,5 +1,5 @@
 import { parse } from "acorn"
-import { Cause, Effect, Exit, Fiber, Scope, Semaphore } from "effect"
+import { Cause, Deferred, Effect, Exit, Fiber, Scope, Semaphore } from "effect"
 import { DiagnosticCategory, ModuleKind, ScriptTarget, flattenDiagnosticMessageText, transpileModule } from "typescript"
 import {
   copyIn,
@@ -31,7 +31,6 @@ import {
   ErrorConstructorReference,
   GlobalMethodReference,
   GlobalNamespace,
-  type GlobalNamespaceName,
   formatLocation,
   getArray,
   getBoolean,
@@ -43,11 +42,14 @@ import {
   isRecord,
   type MemberReference,
   OptionalShortCircuit,
+  PromiseCapabilityFunction,
+  PromiseInstanceMethodReference,
   PromiseMethodReference,
   type PromiseMethodName,
   PromiseNamespace,
   ProgramThrow,
   type ProgramNode,
+  SearchFunction,
   type StatementResult,
   sourceLocation,
   supportedSyntaxMessage,
@@ -56,7 +58,7 @@ import {
 } from "./model.js"
 import { arrayMethods, mapMethods, setMethods, spreadItems } from "../stdlib/collections.js"
 import { consoleMethods, MAX_CONSOLE_DEPTH } from "../stdlib/console.js"
-import { dateMethods, dateStatics, invokeDateMethod, invokeDateStatic } from "../stdlib/date.js"
+import { dateMethods, invokeDateMethod, invokeDateStatic } from "../stdlib/date.js"
 import { invokeJsonMethod } from "../stdlib/json.js"
 import { invokeMathMethod, mathConstants } from "../stdlib/math.js"
 import {
@@ -82,7 +84,6 @@ import {
   urlMethods,
   urlProperties,
   urlSearchParamsMethods,
-  urlStatics,
   urlWritableProperties,
   invokeUriFunction,
   invokeURLMethod,
@@ -95,6 +96,7 @@ import {
   coerceToNumber,
   coerceToString,
   compoundOperators,
+  createAggregateErrorValue,
   createErrorValue,
   errorBrandName,
   errorConstructors,
@@ -219,6 +221,41 @@ const normalizeError = (error: unknown): Diagnostic => {
   }
 }
 
+// V8 parity: a combinator settles one reaction turn after the deciding member, never
+// before reactions already attached to it.
+const settleAfterTurn = <A, E, R>(body: Effect.Effect<A, E, R>): Effect.Effect<A, E, R> =>
+  Effect.flatMap(Effect.exit(body), (exit) => Effect.andThen(Effect.yieldNow, exit))
+
+const selfResolutionError = (node?: AstNode): InterpreterRuntimeError =>
+  new InterpreterRuntimeError("Chaining cycle detected: a promise cannot resolve with itself.", node).as("TypeError")
+
+// Short-circuit marker for Promise.any: the first fulfillment travels the error channel of
+// the flipped members so fail-fast Effect.all stops observing on it.
+class PromiseAnyFulfilled {
+  constructor(readonly value: unknown) {}
+}
+
+type ReactionHandler = CodeModeFunction | CoercionFunction | UriFunction | PromiseCapabilityFunction
+
+// Non-callables are ignored as in JS: `.then(undefined, f)` relies on the passthrough.
+const reactionHandler = (value: unknown, method: string, node: AstNode): ReactionHandler | undefined => {
+  if (
+    value instanceof CodeModeFunction ||
+    value instanceof CoercionFunction ||
+    value instanceof UriFunction ||
+    value instanceof PromiseCapabilityFunction
+  ) {
+    return value
+  }
+  if (typeofValue(value) === "function") {
+    throw new InterpreterRuntimeError(
+      `${method} handlers must be plain functions; wrap other callables in an arrow function, e.g. (value) => tools.ns.tool(value).`,
+      node,
+    )
+  }
+  return undefined
+}
+
 // Shared by catch bindings and Promise.allSettled rejection reasons.
 const caughtErrorValue = (thrown: unknown): unknown => {
   if (thrown instanceof ProgramThrow) return thrown.value
@@ -227,6 +264,21 @@ const caughtErrorValue = (thrown: unknown): unknown => {
   return createErrorValue(name, normalizeError(thrown).message)
 }
 
+// `new Error("msg")` and the no-new call form share this; AggregateError alone takes
+// (errors, message?) with a required errors collection, as in JS.
+const constructErrorValue = (name: string, args: Array<unknown>, node: AstNode): SafeObject => {
+  if (name !== "AggregateError") return createErrorValue(name, args[0] === undefined ? "" : coerceToString(args[0]))
+  const errors = spreadItems(args[0])
+  if (errors === undefined) {
+    throw new InterpreterRuntimeError(
+      "new AggregateError(...) expects an array of errors (e.g. new AggregateError(errors, message?)).",
+      node,
+    ).as("TypeError")
+  }
+  // Copy: spreadItems returns array input itself, and the error value must not alias caller data.
+  return createAggregateErrorValue([...errors], args[1] === undefined ? "" : coerceToString(args[1]))
+}
+
 const isRuntimeReference = (value: unknown): boolean =>
   value instanceof CodeModeFunction ||
   value instanceof ToolReference ||
@@ -235,9 +287,12 @@ const isRuntimeReference = (value: unknown): boolean =>
   value instanceof GlobalMethodReference ||
   value instanceof PromiseNamespace ||
   value instanceof PromiseMethodReference ||
+  value instanceof PromiseInstanceMethodReference ||
   value instanceof SandboxPromise ||
   value instanceof CoercionFunction ||
   value instanceof UriFunction ||
+  value instanceof SearchFunction ||
+  value instanceof PromiseCapabilityFunction ||
   value instanceof ErrorConstructorReference ||
   isSandboxValue(value)
 
@@ -279,11 +334,13 @@ const typeofValue = (value: unknown): string => {
     value instanceof IntrinsicReference ||
     value instanceof GlobalMethodReference ||
     value instanceof PromiseMethodReference ||
+    value instanceof PromiseInstanceMethodReference ||
     value instanceof PromiseNamespace ||
+    value instanceof PromiseCapabilityFunction ||
     value instanceof ErrorConstructorReference
   )
     return "function"
-  if (value instanceof UriFunction) return "function"
+  if (value instanceof UriFunction || value instanceof SearchFunction) return "function"
   if (value instanceof ToolReference) return value.path.length > 0 ? "function" : "object"
   if (value instanceof GlobalNamespace) {
     return value.name === "Math" || value.name === "JSON" || value.name === "console" ? "object" : "function"
@@ -391,7 +448,7 @@ const invokeStringMethod = (value: string, name: string, args: Array<unknown>, n
         break
       }
       if (args[0] instanceof SandboxRegExp) {
-        result = value.split((args[0] as SandboxRegExp).regex, optNum(1))
+        result = value.split(args[0].regex, optNum(1))
         break
       }
       const requestedLimit = optNum(1)
@@ -419,7 +476,7 @@ const invokeStringMethod = (value: string, name: string, args: Array<unknown>, n
     case "replace":
     case "replaceAll": {
       if (args[0] instanceof SandboxRegExp) {
-        const pattern = (args[0] as SandboxRegExp).regex
+        const pattern = args[0].regex
         const replacement = str(1)
         if (name === "replaceAll" && !pattern.global) {
           throw new InterpreterRuntimeError(
@@ -524,9 +581,8 @@ const invokeArrayStatic = (name: string, args: Array<unknown>, node: AstNode): u
         )
       }
       // Map/Set materialize directly (the data checkpoint would serialize them to {}).
-      if (args[0] instanceof SandboxMap)
-        return Array.from((args[0] as SandboxMap).map.entries(), ([key, item]) => [key, item])
-      if (args[0] instanceof SandboxSet) return Array.from((args[0] as SandboxSet).set.values())
+      if (args[0] instanceof SandboxMap) return Array.from(args[0].map.entries(), ([key, item]) => [key, item])
+      if (args[0] instanceof SandboxSet) return Array.from(args[0].set.values())
       if (args[0] instanceof SandboxURLSearchParams) {
         return Array.from(args[0].params.entries(), ([key, value]) => [key, value])
       }
@@ -568,11 +624,7 @@ const invokeGlobalMethod = (ref: GlobalMethodReference, args: Array<unknown>, no
   if (ref.namespace === "Number") return invokeNumberStatic(ref.name, args, node)
   if (ref.namespace === "String") return invokeStringStatic(ref.name, args, node)
   if (ref.namespace === "URL") return invokeURLStatic(ref.name, args, node)
-  if (ref.namespace === "Date") {
-    if (!dateStatics.has(ref.name))
-      throw new InterpreterRuntimeError(`Date.${ref.name} is not available in CodeMode.`, node)
-    return invokeDateStatic(ref.name, args, node)
-  }
+  if (ref.namespace === "Date") return invokeDateStatic(ref.name, args, node)
   if (
     ref.namespace === "RegExp" ||
     ref.namespace === "Map" ||
@@ -688,6 +740,8 @@ class PromiseRuntime<R> {
 class Interpreter<R> {
   private scopes: Array<Map<string, Binding>>
   private readonly invokeTool: (path: ReadonlyArray<string>, args: Array<unknown>) => Effect.Effect<unknown, unknown, R>
+  // The built-in `search` global, threaded from ToolRuntime.make like invokeTool.
+  private readonly invokeSearch: (args: Array<unknown>) => Effect.Effect<unknown, unknown, R>
   // Enumerable namespace/tool names at a node of the host tool tree, threaded from
   // ToolRuntime.make like invokeTool: the interpreter never holds the tree itself.
   private readonly toolKeys: (path: ReadonlyArray<string>) => ReadonlyArray<string>
@@ -698,6 +752,7 @@ class Interpreter<R> {
 
   constructor(
     invokeTool: (path: ReadonlyArray<string>, args: Array<unknown>) => Effect.Effect<unknown, unknown, R>,
+    invokeSearch: (args: Array<unknown>) => Effect.Effect<unknown, unknown, R>,
     toolKeys: (path: ReadonlyArray<string>) => ReadonlyArray<string>,
     promises: PromiseRuntime<R>,
     logs: Array<string> = [],
@@ -706,11 +761,13 @@ class Interpreter<R> {
     const globalScope = new Map<string, Binding>()
     this.scopes = [globalScope]
     this.invokeTool = invokeTool
+    this.invokeSearch = invokeSearch
     this.toolKeys = toolKeys
     this.logs = logs
     this.callPermits = callPermits
     this.promises = promises
     globalScope.set("tools", { mutable: false, value: new ToolReference([]) })
+    globalScope.set("search", { mutable: false, value: new SearchFunction() })
     globalScope.set("Promise", { mutable: false, value: new PromiseNamespace() })
     globalScope.set("undefined", { mutable: false, value: undefined })
     globalScope.set("Object", { mutable: false, value: new GlobalNamespace("Object") })
@@ -768,7 +825,6 @@ class Interpreter<R> {
         if (result.kind === "break" || result.kind === "continue") {
           throw new InterpreterRuntimeError(`Unexpected '${result.kind}' outside of a loop.`, statement)
         }
-
       }
 
       // The program body runs inside an implicit async function, so a returned promise
@@ -794,16 +850,14 @@ class Interpreter<R> {
     return this.promises.create(effect)
   }
 
-  // `await promise`: succeed with the fulfilled value or re-raise the failure so try/catch
-  // observes it exactly like a synchronous throw at the await site. Settlement is idempotent
-  // (fiber exits replay), so awaiting the same promise repeatedly never re-runs the call.
+  // Settlement is idempotent (fiber exits replay), so awaiting the same promise repeatedly
+  // never re-runs the call. The post-settlement yield defers the continuation one reaction
+  // turn, as in JS: awaiters never resume inline, so they interleave in attach order.
   private settlePromise(promise: SandboxPromise): Effect.Effect<unknown, unknown, never> {
     const promises = this.promises
     return Effect.suspend(() => {
       promises.markObserved(promise)
-      return Effect.flatMap(promises.await(promise), (exit) =>
-        Exit.isSuccess(exit) ? Effect.succeed(exit.value) : Effect.failCause(exit.cause),
-      )
+      return Effect.flatMap(promises.await(promise), (exit) => Effect.andThen(Effect.yieldNow, exit))
     })
   }
 
@@ -980,7 +1034,6 @@ class Interpreter<R> {
         if (result.kind === "return") {
           return result
         }
-
       }
 
       return { kind: "none" } satisfies StatementResult
@@ -1007,7 +1060,6 @@ class Interpreter<R> {
         if (result.kind === "return") {
           return result
         }
-
       } while (yield* self.evaluateExpression(testNode))
 
       return { kind: "none" } satisfies StatementResult
@@ -1037,16 +1089,13 @@ class Interpreter<R> {
           : []
 
       while (testNode ? yield* self.evaluateExpression(testNode) : true) {
-        let iterationScope: Map<string, Binding> | undefined
-        if (perIterationBindings.length > 0) {
-          iterationScope = new Map(
-            perIterationBindings.map((name) => {
-              const binding = self.currentScope().get(name)!
-              return [name, { ...binding }]
-            }),
-          )
-          self.scopes.push(iterationScope)
-        }
+        const iterationScope =
+          perIterationBindings.length > 0
+            ? new Map(
+                perIterationBindings.map((name): [string, Binding] => [name, { ...self.currentScope().get(name)! }]),
+              )
+            : undefined
+        if (iterationScope) self.scopes.push(iterationScope)
         const result = yield* self.evaluateStatement(bodyNode).pipe(
           Effect.ensuring(
             Effect.sync(() => {
@@ -1096,7 +1145,7 @@ class Interpreter<R> {
 
       // Arrays iterate in place; strings iterate code points; Maps iterate [key, value]
       // pairs and Sets iterate values over a snapshot (mutation during iteration is safe).
-      const iterable = Array.isArray(right) ? right : spreadItems(right)
+      const iterable = spreadItems(right)
       if (iterable === undefined) {
         throw new InterpreterRuntimeError("for...of requires an array, string, Map, or Set value in CodeMode.", node)
       }
@@ -1550,11 +1599,10 @@ class Interpreter<R> {
       case "UpdateExpression":
         return this.evaluateUpdateExpression(node)
       case "AwaitExpression": {
-        // `await` resolves a promise value; awaiting anything else is a passthrough no-op,
-        // matching real JS semantics for non-thenables.
+        // In JS every await suspends, even on a non-promise.
         const self = this
         return Effect.flatMap(this.evaluateExpression(getNode(node, "argument")), (value) =>
-          value instanceof SandboxPromise ? self.settlePromise(value) : Effect.succeed(value),
+          value instanceof SandboxPromise ? self.settlePromise(value) : Effect.as(Effect.yieldNow, value),
         )
       }
       case "NewExpression":
@@ -1573,19 +1621,10 @@ class Interpreter<R> {
     const argNodes = getArray(node, "arguments")
     const self = this
     if (name === "Promise") {
-      throw new InterpreterRuntimeError(
-        "new Promise(...) is not supported in CodeMode; tool calls already return promises - call the tool and await the result.",
-        node,
-        "UnsupportedSyntax",
-        [supportedSyntaxMessage],
-      )
+      return Effect.flatMap(this.evaluateCallArguments(argNodes), (args) => self.constructPromise(args[0], node))
     }
     if (errorConstructors.has(name)) {
-      return Effect.gen(function* () {
-        const arg =
-          argNodes.length > 0 ? yield* self.evaluateExpression(asNode(argNodes[0], "arguments[0]")) : undefined
-        return createErrorValue(name, arg === undefined ? "" : coerceToString(arg))
-      })
+      return Effect.map(this.evaluateCallArguments(argNodes), (args) => constructErrorValue(name, args, node))
     }
     if (valueConstructors.has(name)) {
       return Effect.gen(function* () {
@@ -1923,7 +1962,7 @@ class Interpreter<R> {
           return self.setIdentifierValue(name, next, left)
         }
         const rightValue = yield* self.evaluateExpression(getNode(node, "right"))
-        if (operator === "=") return self.setIdentifierValue(name, rightValue, left)
+        return self.setIdentifierValue(name, rightValue, left)
       }
       if (left.type === "MemberExpression") {
         return yield* self.modifyMember(left, (current) =>
@@ -2025,6 +2064,9 @@ class Interpreter<R> {
       if (callable instanceof PromiseMethodReference) {
         return yield* self.invokePromiseMethod(callable, args, node)
       }
+      if (callable instanceof PromiseInstanceMethodReference) {
+        return yield* self.invokePromiseInstanceMethod(callable, args, node)
+      }
       if (callable instanceof CodeModeFunction) {
         return yield* self.invokeFunction(callable, args)
       }
@@ -2050,9 +2092,18 @@ class Interpreter<R> {
       if (callable instanceof UriFunction) {
         return invokeUriFunction(callable, args, node)
       }
+      if (callable instanceof SearchFunction) {
+        // The built-in search is synchronous in-memory matching: the call returns its
+        // result directly (await still works, as with any plain value).
+        return yield* self.invokeSearch(args)
+      }
       // `Error("msg")` without `new` constructs an error exactly like `new Error("msg")`, as in JS.
       if (callable instanceof ErrorConstructorReference) {
-        return createErrorValue(callable.name, args[0] === undefined ? "" : coerceToString(args[0]))
+        return constructErrorValue(callable.name, args, node)
+      }
+      if (callable instanceof PromiseCapabilityFunction) {
+        callable.settle(args[0])
+        return undefined
       }
       throw new InterpreterRuntimeError("Only tools are callable in CodeMode.", callee)
     })
@@ -2067,7 +2118,7 @@ class Interpreter<R> {
       return boundedData(this.enumerableKeys(ref)!, "Object.keys result")
     }
     throw new InterpreterRuntimeError(
-      `Object.${name}(...) cannot read tool references: they are not plain data. Use Object.keys(tools) for names, or tools.$codemode.search({ query }) for signatures.`,
+      `Object.${name}(...) cannot read tool references: they are not plain data. Use Object.keys(tools) for names, or search({ query }) for signatures.`,
       node,
       "InvalidDataValue",
     )
@@ -2241,17 +2292,19 @@ class Interpreter<R> {
       return this.createPromise(Effect.fail(new ProgramThrow(args[0])))
     }
 
-    const items = Array.isArray(args[0]) ? args[0] : spreadItems(args[0])
-    if (items === undefined) {
+    const spread = spreadItems(args[0])
+    if (spread === undefined) {
       return this.createPromise(
         Effect.fail(
           new InterpreterRuntimeError(
             `Promise.${ref.name} expects an array of promises or plain values (e.g. Promise.${ref.name}(items.map((item) => tools.ns.tool(item)))).`,
             node,
-          ),
+          ).as("TypeError"),
         ),
       )
     }
+    // Densify: JS combinator iteration reads sparse holes as undefined members; .map would skip them.
+    const items = Array.from(spread)
 
     // JS makes combinator members "handled" synchronously at the call - their rejections
     // belong to the aggregate from this moment, even ones settling before it runs.
@@ -2261,47 +2314,42 @@ class Interpreter<R> {
 
     switch (ref.name) {
       case "all": {
-        // Each observation re-raises its member's failure, so Effect.all rejects on the first
-        // failure without waiting for the rest and preserves input order when all fulfill.
-        // Its failure-time interruption only unsubscribes the sibling waiters: the underlying
-        // fibers stay execution-owned and keep running, as in JS.
+        // Rejects on the first failure; sibling fibers stay execution-owned and keep running, as in JS.
         const observations = items.map((item) =>
-          item instanceof SandboxPromise
-            ? Effect.flatMap(this.promises.await(item), (exit) =>
-                Exit.isSuccess(exit) ? Effect.succeed(exit.value) : Effect.failCause(exit.cause),
-              )
-            : Effect.succeed(item),
+          item instanceof SandboxPromise ? Effect.flatten(this.promises.await(item)) : Effect.succeed(item),
         )
-        return this.createPromise(Effect.all(observations, { concurrency: "unbounded" }))
+        return this.createPromise(settleAfterTurn(Effect.all(observations, { concurrency: "unbounded" })))
       }
       case "allSettled": {
         const observations = items.map((item) =>
-          item instanceof SandboxPromise ? this.promises.await(item) : Effect.succeed(Exit.succeed(item as unknown)),
+          item instanceof SandboxPromise ? this.promises.await(item) : Effect.succeed(Exit.succeed(item)),
         )
         return this.createPromise(
-          Effect.gen(function* () {
-            const outcomes: Array<unknown> = []
-            for (const observation of observations) {
-              const exit = yield* observation
-              if (Exit.isSuccess(exit)) {
+          settleAfterTurn(
+            Effect.gen(function* () {
+              const outcomes: Array<unknown> = []
+              for (const observation of observations) {
+                const exit = yield* observation
+                if (Exit.isSuccess(exit)) {
+                  outcomes.push(
+                    Object.assign(Object.create(null) as SafeObject, { status: "fulfilled", value: exit.value }),
+                  )
+                  continue
+                }
+                if (Cause.hasInterruptsOnly(exit.cause)) {
+                  // Execution teardown (timeout/host interruption), not a program-level rejection.
+                  return yield* Effect.failCause(exit.cause)
+                }
                 outcomes.push(
-                  Object.assign(Object.create(null) as SafeObject, { status: "fulfilled", value: exit.value }),
+                  Object.assign(Object.create(null) as SafeObject, {
+                    status: "rejected",
+                    reason: caughtErrorValue(Cause.squash(exit.cause)),
+                  }),
                 )
-                continue
               }
-              if (Cause.hasInterruptsOnly(exit.cause)) {
-                // Execution teardown (timeout/host interruption), not a program-level rejection.
-                return yield* Effect.failCause(exit.cause)
-              }
-              outcomes.push(
-                Object.assign(Object.create(null) as SafeObject, {
-                  status: "rejected",
-                  reason: caughtErrorValue(Cause.squash(exit.cause)),
-                }),
-              )
-            }
-            return outcomes
-          }),
+              return outcomes
+            }),
+          ),
         )
       }
       case "race": {
@@ -2316,21 +2364,155 @@ class Interpreter<R> {
           )
         }
         const observations = items.map((item) =>
-          item instanceof SandboxPromise ? this.promises.await(item) : Effect.succeed(Exit.succeed(item as unknown)),
+          item instanceof SandboxPromise ? this.promises.await(item) : Effect.succeed(Exit.succeed(item)),
         )
         // First settlement (fulfilled OR rejected) wins; losing work stays execution-owned
         // and is interrupted at normal completion (already observed) or by teardown.
-        return this.createPromise(
-          Effect.flatMap(Effect.raceAll(observations), (exit) =>
-            Exit.isSuccess(exit) ? Effect.succeed(exit.value) : Effect.failCause(exit.cause),
+        return this.createPromise(settleAfterTurn(Effect.flatten(Effect.raceAll(observations))))
+      }
+      case "any": {
+        // De Morgan dual of Promise.all: members are flipped so the first fulfillment
+        // short-circuits fail-fast Effect.all, and all-rejected completes with the reasons
+        // in input order for the AggregateError.
+        const flipped = items.map((item) =>
+          item instanceof SandboxPromise
+            ? Effect.flatMap(this.promises.await(item), (exit) => {
+                if (Exit.isSuccess(exit)) return Effect.fail(new PromiseAnyFulfilled(exit.value))
+                if (Cause.hasInterruptsOnly(exit.cause)) return Effect.failCause(exit.cause)
+                return Effect.succeed(caughtErrorValue(Cause.squash(exit.cause)))
+              })
+            : Effect.fail(new PromiseAnyFulfilled(item)),
+        )
+        const body = Effect.all(flipped, { concurrency: "unbounded" }).pipe(
+          Effect.flatMap((reasons) =>
+            Effect.fail(new ProgramThrow(createAggregateErrorValue(reasons, "All promises were rejected"))),
+          ),
+          Effect.catch((error) =>
+            error instanceof PromiseAnyFulfilled ? Effect.succeed(error.value) : Effect.fail(error),
           ),
         )
+        return this.createPromise(settleAfterTurn(body))
       }
     }
   }
 
+  // Teardown interruption propagates without running handlers; a real settlement defers
+  // one reaction turn so handlers never run inline.
+  private reactionExit(source: SandboxPromise): Effect.Effect<Exit.Exit<unknown, unknown>, unknown, R> {
+    const promises = this.promises
+    return Effect.gen(function* () {
+      const exit = yield* promises.await(source)
+      if (!Exit.isSuccess(exit) && Cause.hasInterruptsOnly(exit.cause)) return yield* Effect.failCause(exit.cause)
+      yield* Effect.yieldNow
+      return exit
+    })
+  }
+
+  private invokePromiseInstanceMethod(
+    ref: PromiseInstanceMethodReference,
+    args: Array<unknown>,
+    node: AstNode,
+  ): Effect.Effect<SandboxPromise, never, R> {
+    const method = `Promise.prototype.${ref.name}`
+    this.promises.markObserved(ref.promise)
+    if (ref.name === "finally") {
+      return this.chainFinally(ref.promise, reactionHandler(args[0], method, node), method, node)
+    }
+    const onFulfilled = ref.name === "then" ? reactionHandler(args[0], method, node) : undefined
+    const onRejected = reactionHandler(ref.name === "then" ? args[1] : args[0], method, node)
+    return this.chainReaction(ref.promise, onFulfilled, onRejected, method, node)
+  }
+
+  private chainReaction(
+    source: SandboxPromise,
+    onFulfilled: ReactionHandler | undefined,
+    onRejected: ReactionHandler | undefined,
+    method: string,
+    node: AstNode,
+  ): Effect.Effect<SandboxPromise, never, R> {
+    const self = this
+    const box: { derived?: SandboxPromise } = {}
+    const body = Effect.gen(function* () {
+      const exit = yield* self.reactionExit(source)
+      const handler = Exit.isSuccess(exit) ? onFulfilled : onRejected
+      if (handler === undefined) return yield* exit
+      const input = Exit.isSuccess(exit) ? exit.value : caughtErrorValue(Cause.squash(exit.cause))
+      const result = yield* self.applyCollectionCallback(handler, method, node)([input])
+      if (result === box.derived) return yield* Effect.fail(selfResolutionError(node))
+      if (result instanceof SandboxPromise) return yield* self.settlePromise(result)
+      return result
+    })
+    return Effect.map(this.createPromise(body), (derived) => {
+      box.derived = derived
+      return derived
+    })
+  }
+
+  private chainFinally(
+    source: SandboxPromise,
+    cleanup: ReactionHandler | undefined,
+    method: string,
+    node: AstNode,
+  ): Effect.Effect<SandboxPromise, never, R> {
+    const self = this
+    return this.createPromise(
+      Effect.gen(function* () {
+        const exit = yield* self.reactionExit(source)
+        if (cleanup !== undefined) {
+          const result = yield* self.applyCollectionCallback(cleanup, method, node)([])
+          if (result instanceof SandboxPromise) yield* self.settlePromise(result)
+        }
+        return yield* exit
+      }),
+    )
+  }
+
+  // new Promise(executor): the promise's fiber awaits a Deferred that resolve/reject settle
+  // exactly once. The executor runs synchronously; its throw rejects the promise unless it
+  // already settled (JS swallows post-settlement executor throws).
+  private constructPromise(executor: unknown, node: AstNode): Effect.Effect<SandboxPromise, unknown, R> {
+    if (!(executor instanceof CodeModeFunction)) {
+      throw new InterpreterRuntimeError(
+        "new Promise(...) expects an executor function (e.g. new Promise((resolve, reject) => { ... })).",
+        node,
+      ).as("TypeError")
+    }
+    const self = this
+    return Effect.gen(function* () {
+      const deferred = Deferred.makeUnsafe<unknown, unknown>()
+      const box: { own?: SandboxPromise } = {}
+      const promise = yield* self.createPromise(
+        Effect.flatMap(Deferred.await(deferred), (value) => {
+          if (!(value instanceof SandboxPromise)) return Effect.succeed(value)
+          if (value === box.own) return Effect.fail(selfResolutionError(node))
+          return self.settlePromise(value)
+        }),
+      )
+      box.own = promise
+      const resolve = new PromiseCapabilityFunction((value) => {
+        Deferred.doneUnsafe(deferred, Exit.succeed(value))
+      })
+      const reject = new PromiseCapabilityFunction((value) => {
+        Deferred.doneUnsafe(deferred, Exit.fail(new ProgramThrow(value)))
+      })
+      const executed = yield* Effect.exit(self.invokeFunction(executor, [resolve, reject]))
+      if (!Exit.isSuccess(executed)) {
+        if (Cause.hasInterruptsOnly(executed.cause)) return yield* Effect.failCause(executed.cause)
+        Deferred.doneUnsafe(deferred, Exit.fail(Cause.squash(executed.cause)))
+      }
+      return promise
+    })
+  }
+
   private invokeFunction(fn: CodeModeFunction, args: Array<unknown>): Effect.Effect<unknown, unknown, R> {
-    const invocation = new Interpreter(this.invokeTool, this.toolKeys, this.promises, this.logs, this.callPermits)
+    const invocation = new Interpreter(
+      this.invokeTool,
+      this.invokeSearch,
+      this.toolKeys,
+      this.promises,
+      this.logs,
+      this.callPermits,
+    )
     invocation.scopes = [...fn.capturedScopes, new Map<string, Binding>()]
     const run = Effect.gen(function* () {
       // Seed every parameter name into the scope as a TDZ slot first, so a default that
@@ -2358,10 +2540,20 @@ class Interpreter<R> {
       return yield* invocation.evaluateExpression(fn.body)
     })
     if (!fn.async) return run
-    return this.createPromise(
-      Effect.flatMap(run, (value) =>
-        value instanceof SandboxPromise ? invocation.settlePromise(value) : Effect.succeed(value),
+    // Every await yields, so `box.own` is assigned before the body can return a reference to it.
+    const box: { own?: SandboxPromise } = {}
+    return Effect.map(
+      this.createPromise(
+        Effect.flatMap(run, (value) => {
+          if (!(value instanceof SandboxPromise)) return Effect.succeed(value)
+          if (value === box.own) return Effect.fail(selfResolutionError())
+          return invocation.settlePromise(value)
+        }),
       ),
+      (promise) => {
+        box.own = promise
+        return promise
+      },
     )
   }
 
@@ -2472,8 +2664,8 @@ class Interpreter<R> {
     })
   }
 
-  // Runs a collection callback accepting a user function or supported builtin callable,
-  // mirroring the array-method callback contract.
+  // Accepts a user function or supported builtin callable, so idioms such as
+  // `filter(Boolean)`, `map(String)`, and `map(encodeURIComponent)` work as in JS.
   private applyCollectionCallback(
     callback: unknown,
     name: string,
@@ -2482,7 +2674,8 @@ class Interpreter<R> {
     if (
       !(callback instanceof CodeModeFunction) &&
       !(callback instanceof CoercionFunction) &&
-      !(callback instanceof UriFunction)
+      !(callback instanceof UriFunction) &&
+      !(callback instanceof PromiseCapabilityFunction)
     ) {
       throw new InterpreterRuntimeError(`${name} expects a function callback.`, node)
     }
@@ -2491,7 +2684,9 @@ class Interpreter<R> {
         ? Effect.succeed(invokeCoercion(callback, callbackArgs, node))
         : callback instanceof UriFunction
           ? Effect.succeed(invokeUriFunction(callback, callbackArgs, node))
-          : this.invokeFunction(callback, callbackArgs)
+          : callback instanceof PromiseCapabilityFunction
+            ? Effect.sync(() => callback.settle(callbackArgs[0]))
+            : this.invokeFunction(callback, callbackArgs)
   }
 
   private invokeMapMethod(
@@ -2761,24 +2956,7 @@ class Interpreter<R> {
         return Effect.succeed(Array.from(target.entries(), ([index, item]): Array<unknown> => [index, item]))
     }
 
-    const callback = args[0]
-    if (
-      !(callback instanceof CodeModeFunction) &&
-      !(callback instanceof CoercionFunction) &&
-      !(callback instanceof UriFunction)
-    ) {
-      throw new InterpreterRuntimeError(`Array.${name} expects a function callback.`, node)
-    }
-    const self = this
-    // Accept a user function or supported builtin callable, so idioms such as
-    // `filter(Boolean)`, `map(String)`, and `map(encodeURIComponent)` work as in JS. Builtins
-    // are synchronous; only CodeModeFunctions can await tool calls.
-    const apply = (callbackArgs: Array<unknown>): Effect.Effect<unknown, unknown, R> =>
-      callback instanceof CoercionFunction
-        ? Effect.succeed(invokeCoercion(callback, callbackArgs, node))
-        : callback instanceof UriFunction
-          ? Effect.succeed(invokeUriFunction(callback, callbackArgs, node))
-          : self.invokeFunction(callback, callbackArgs)
+    const apply = this.applyCollectionCallback(args[0], `Array.${name}`, node)
     return Effect.gen(function* () {
       // Capture the initial length, but read the receiver live so callbacks observe mutations
       // without visiting elements appended after iteration begins.
@@ -3079,6 +3257,7 @@ class Interpreter<R> {
     | MemberReference
     | ToolReference
     | PromiseMethodReference
+    | PromiseInstanceMethodReference
     | IntrinsicReference
     | GlobalMethodReference
     | ComputedValue
@@ -3115,7 +3294,7 @@ class Interpreter<R> {
           return new PromiseMethodReference(key as PromiseMethodName)
         }
         throw new InterpreterRuntimeError(
-          `Promise.${String(key)} is not available in CodeMode. Available: Promise.all, Promise.allSettled, Promise.race, Promise.resolve, and Promise.reject; consume promises with await.`,
+          `Promise.${String(key)} is not available in CodeMode. Available: Promise.all, Promise.allSettled, Promise.race, Promise.any, Promise.resolve, and Promise.reject; consume promises with await.`,
           propertyNode,
         )
       }
@@ -3199,20 +3378,13 @@ class Interpreter<R> {
         return new ComputedValue(undefined)
       }
 
-      // Any property access on a promise is a confused program (`p.then(...)`, `p.value`);
-      // reading `undefined` here would hide the missing await, so both paths get an explicit,
-      // await-hinting error instead of the forgiving unknown-property fallthrough.
+      // Error instead of `undefined` so a missing await never hides.
       if (objectValue instanceof SandboxPromise) {
         if (key === "then" || key === "catch" || key === "finally") {
-          throw new InterpreterRuntimeError(
-            `Promise.prototype.${String(key)} is not supported in CodeMode; use await instead (with try/catch to handle failures) - e.g. \`const result = await tools.ns.tool(...)\`.`,
-            propertyNode,
-            "UnsupportedSyntax",
-            [supportedSyntaxMessage],
-          )
+          return new PromiseInstanceMethodReference(objectValue, key)
         }
         throw new InterpreterRuntimeError(
-          "This value is an un-awaited Promise and has no readable properties; await it first - e.g. `const result = await tools.ns.tool(...)`.",
+          "This value is an un-awaited Promise; await it first - e.g. `const result = await tools.ns.tool(...)`.",
           objectNode,
           "InvalidDataValue",
         )
@@ -3265,6 +3437,7 @@ class Interpreter<R> {
         reference === undefined ||
         reference instanceof ToolReference ||
         reference instanceof PromiseMethodReference ||
+        reference instanceof PromiseInstanceMethodReference ||
         reference instanceof IntrinsicReference ||
         reference instanceof GlobalMethodReference
       )
@@ -3302,6 +3475,7 @@ class Interpreter<R> {
         reference === undefined ||
         reference instanceof ToolReference ||
         reference instanceof PromiseMethodReference ||
+        reference instanceof PromiseInstanceMethodReference ||
         reference instanceof IntrinsicReference ||
         reference instanceof GlobalMethodReference
       ) {
@@ -3489,15 +3663,14 @@ export const executeWithLimits = <const Tools extends Record<string, unknown>>(
   // and the timeout path's completed value - binds at run time: a reused Effect must start
   // from a clean slate instead of observing a previous run's state.
   return Effect.suspend(() => {
-    const hooks = {
-      ...(options.onToolCallStart === undefined ? {} : { onToolCallStart: options.onToolCallStart }),
-      ...(options.onToolCallEnd === undefined ? {} : { onToolCallEnd: options.onToolCallEnd }),
-    }
     const tools = ToolRuntime.make(
       (options.tools ?? {}) as HostTools<Services<Tools>>,
       limits.maxToolCalls,
       searchIndex,
-      hooks,
+      {
+        onToolCallStart: options.onToolCallStart,
+        onToolCallEnd: options.onToolCallEnd,
+      },
     )
     const logs: Array<string> = []
     const logged = () => (logs.length > 0 ? { logs: [...logs] } : {})
@@ -3512,7 +3685,7 @@ export const executeWithLimits = <const Tools extends Record<string, unknown>>(
         Effect.gen(function* () {
           const program = parseProgram(options.code)
           const promises = new PromiseRuntime<Services<Tools>>(scope)
-          const interpreter = new Interpreter<Services<Tools>>(tools.invoke, tools.keys, promises, logs)
+          const interpreter = new Interpreter<Services<Tools>>(tools.invoke, tools.search, tools.keys, promises, logs)
           const value = yield* interpreter.run(program)
           // Validate the result first so an invalid value is a fatal completion that closes
           // the promise scope directly instead of taking the normal-completion path.

packages/codemode/src/openapi/runtime.ts

@@ -46,9 +46,7 @@ export const invoke = (plan: Plan, input: unknown): Effect.Effect<unknown, unkno
       )
     }
     if (json && Option.isNone(decoded)) {
-      return yield* Effect.fail(
-        toolError(`${plan.operation.method} ${plan.operation.path} returned malformed JSON.`),
-      )
+      return yield* Effect.fail(toolError(`${plan.operation.method} ${plan.operation.path} returned malformed JSON.`))
     }
     return parsed
   })
@@ -208,8 +206,9 @@ const buildUrl = (plan: Plan, input: Readonly<Record<string, unknown>>): string
       return toolError(`Missing required path parameter '${field.inputName}'.`)
     }
     const fieldValue = serializeSimple(field, item, (value) =>
-      encodeURIComponent(value).replace(/[!'()*]/g, (character) =>
-        `%${character.charCodeAt(0).toString(16).toUpperCase()}`,
+      encodeURIComponent(value).replace(
+        /[!'()*]/g,
+        (character) => `%${character.charCodeAt(0).toString(16).toUpperCase()}`,
       ),
     )
     if (fieldValue instanceof ToolError) return fieldValue
@@ -271,10 +270,7 @@ const serializeQuery = (
     if (value.some((item) => item === undefined || (item !== null && typeof item === "object"))) {
       return toolError(`Query parameter '${field.inputName}' contains an unsupported nested value.`)
     }
-    return value.reduce(
-      (current, item) => HttpClientRequest.appendUrlParam(current, field.name, String(item)),
-      request,
-    )
+    return value.reduce((current, item) => HttpClientRequest.appendUrlParam(current, field.name, String(item)), request)
   }
   if (isRecord(value) && field.explode) {
     return Object.entries(value).reduce<HttpClientRequest.HttpClientRequest | ToolError>((current, [name, item]) => {
@@ -289,11 +285,15 @@ const serializeQuery = (
   return rendered instanceof ToolError ? rendered : HttpClientRequest.appendUrlParam(request, field.name, rendered)
 }
 
-const readResponseBody = (response: HttpClientResponse.HttpClientResponse, plan: Plan): Effect.Effect<string, ToolError> =>
+const readResponseBody = (
+  response: HttpClientResponse.HttpClientResponse,
+  plan: Plan,
+): Effect.Effect<string, ToolError> =>
   Effect.gen(function* () {
     const contentLength = response.headers["content-length"]
     const parsedSize = contentLength === undefined ? undefined : Number.parseInt(contentLength, 10)
-    const declaredSize = parsedSize !== undefined && Number.isSafeInteger(parsedSize) && parsedSize >= 0 ? parsedSize : undefined
+    const declaredSize =
+      parsedSize !== undefined && Number.isSafeInteger(parsedSize) && parsedSize >= 0 ? parsedSize : undefined
     if (declaredSize !== undefined && declaredSize > maxResponseBodyBytes) {
       return yield* Effect.fail(toolError(`${plan.operation.method} ${plan.operation.path} response exceeds 50 MiB.`))
     }
@@ -304,7 +304,9 @@ const readResponseBody = (response: HttpClientResponse.HttpClientResponse, plan:
         return Effect.fail(toolError(`${plan.operation.method} ${plan.operation.path} response exceeds 50 MiB.`))
       }
       if (size + chunk.byteLength > body.byteLength) {
-        const grown = Buffer.allocUnsafe(Math.min(maxResponseBodyBytes, Math.max(size + chunk.byteLength, body.byteLength * 2)))
+        const grown = Buffer.allocUnsafe(
+          Math.min(maxResponseBodyBytes, Math.max(size + chunk.byteLength, body.byteLength * 2)),
+        )
         body.copy(grown, 0, 0, size)
         body = grown
       }

packages/codemode/src/openapi/spec.ts

@@ -78,7 +78,9 @@ const isBinaryMediaType = (document: Document, mediaType: string, value: unknown
   return isRecord(schema) && schema.format === "binary"
 }
 
-const jsonContent = (content: Record<string, unknown>): { readonly mediaType: string; readonly schema: unknown } | undefined => {
+const jsonContent = (
+  content: Record<string, unknown>,
+): { readonly mediaType: string; readonly schema: unknown } | undefined => {
   const entry = Object.entries(content).find(([mediaType]) => isJsonMediaType(mediaType))
   return entry !== undefined && isRecord(entry[1]) ? { mediaType: entry[0], schema: entry[1].schema } : undefined
 }
@@ -344,7 +346,7 @@ export const operationOutput = (
   if (outcomes.length === 0) return { ok: true, value: undefined }
   return {
     ok: true,
-    value: withDefinitions(outcomes.length === 1 ? outcomes[0] ?? {} : { anyOf: outcomes }, definitions),
+    value: withDefinitions(outcomes.length === 1 ? (outcomes[0] ?? {}) : { anyOf: outcomes }, definitions),
   }
 }
 
@@ -380,7 +382,9 @@ export const operationPath = (
   namespaces: ReadonlySet<string>,
 ): ReadonlyArray<string> => {
   const raw = nonEmptyString(operation.operationId)
-  const segments = (raw === undefined ? [fallbackOperationId(method, path)] : raw.split(".")).map(sanitizeOperationSegment)
+  const segments = (raw === undefined ? [fallbackOperationId(method, path)] : raw.split(".")).map(
+    sanitizeOperationSegment,
+  )
   if (isOperationPathAvailable(segments, used, namespaces)) return segments
   const conflict = segments.slice(0, -1).findIndex((_, index) => used.has(segments.slice(0, index + 1).join(".")))
   if (conflict >= 0 && conflict + 1 < segments.length) {

packages/codemode/src/stdlib/date.ts

@@ -23,8 +23,6 @@ export const dateMethods = new Set([
   "getTimezoneOffset",
 ])
 
-export const dateStatics = new Set(["now", "parse", "UTC"])
-
 export const invokeDateStatic = (name: string, args: Array<unknown>, node: AstNode): number => {
   switch (name) {
     case "now":

packages/codemode/src/stdlib/json.ts

@@ -6,10 +6,7 @@ import {
 } from "../interpreter/model.js"
 import { copyIn, copyOut } from "../tool-runtime.js"
 
-export const jsonStatics = new Set(["stringify", "parse"])
-
 export const invokeJsonMethod = (name: string, args: Array<unknown>, node: AstNode): unknown => {
-  if (!jsonStatics.has(name)) throw new InterpreterRuntimeError(`JSON.${name} is not available in CodeMode.`, node)
   switch (name) {
     case "stringify": {
       const replacer = args[1]

packages/codemode/src/stdlib/object.ts

@@ -3,11 +3,9 @@ import { isBlockedMember } from "../tool-runtime.js"
 import { isSandboxValue, SandboxMap, SandboxPromise, SandboxSet, SandboxURLSearchParams } from "../values.js"
 import { boundedData, coerceToString } from "./value.js"
 
-export const objectStatics = new Set(["keys", "values", "entries", "hasOwn", "assign", "fromEntries"])
 export const objectMethodsPreservingIdentity = new Set(["assign", "values", "entries", "fromEntries"])
 
 export const invokeObjectMethod = (name: string, args: Array<unknown>, node: AstNode): unknown => {
-  if (!objectStatics.has(name)) throw new InterpreterRuntimeError(`Object.${name} is not available in CodeMode.`, node)
   const requireObject = (): Record<string, unknown> => {
     const input = args[0]
     if (Array.isArray(input)) return input as unknown as Record<string, unknown>
@@ -53,13 +51,11 @@ export const invokeObjectMethod = (name: string, args: Array<unknown>, node: Ast
       }
       const out = target as Record<string, unknown>
       for (const source of args.slice(1)) {
-        if (source === null || source === undefined) continue
-        const value = source
-        if (isSandboxValue(value)) continue
-        if (value === null || typeof value !== "object" || Array.isArray(value)) {
+        if (source === null || source === undefined || isSandboxValue(source)) continue
+        if (typeof source !== "object" || Array.isArray(source)) {
           throw new InterpreterRuntimeError("Object.assign expects data objects.", node)
         }
-        for (const [key, item] of Object.entries(value)) guardedSet(out, key, item)
+        for (const [key, item] of Object.entries(source)) guardedSet(out, key, item)
       }
       return out
     }

packages/codemode/src/stdlib/promise.ts

@@ -1,6 +1,6 @@
 import type { PromiseMethodName } from "../interpreter/model.js"
 
-export const promiseStatics = new Set<PromiseMethodName>(["all", "allSettled", "race", "resolve", "reject"])
+export const promiseStatics = new Set<PromiseMethodName>(["all", "allSettled", "race", "any", "resolve", "reject"])
 
 /** Maximum number of eagerly forked tool calls that may run concurrently. */
 export const TOOL_CALL_CONCURRENCY = 8

packages/codemode/src/stdlib/value.ts

@@ -6,6 +6,7 @@ export const errorConstructors = new Set([
   "ReferenceError",
   "EvalError",
   "URIError",
+  "AggregateError",
 ])
 
 export const valueConstructors = new Set(["Date", "RegExp", "Map", "Set", "URL", "URLSearchParams"])
@@ -20,6 +21,9 @@ export const createErrorValue = (name: string, message: string): SafeObject => {
   return value
 }
 
+export const createAggregateErrorValue = (errors: Array<unknown>, message: string): SafeObject =>
+  Object.assign(createErrorValue("AggregateError", message), { errors })
+
 export const errorBrandName = (value: unknown): string | undefined =>
   value !== null && typeof value === "object"
     ? ((value as Record<PropertyKey, unknown>)[ErrorBrand] as string | undefined)
@@ -60,7 +64,7 @@ export const invokeCoercion = (ref: CoercionFunction, args: Array<unknown>, node
     if (ref.name === "parseInt") return parseInt(coerceToString(raw))
     return parseFloat(coerceToString(raw))
   }
-  const value = boundedData(args[0], `${ref.name} input`)
+  const value = boundedData(raw, `${ref.name} input`)
   if (ref.name === "Number") return coerceToNumber(value)
   if (ref.name === "Boolean") return Boolean(value)
   if (ref.name === "parseInt") {
@@ -73,11 +77,7 @@ export const invokeCoercion = (ref: CoercionFunction, args: Array<unknown>, node
   if (ref.name === "parseFloat") return parseFloat(coerceToString(value))
   return coerceToString(value)
 }
-import {
-  type AstNode,
-  CoercionFunction,
-  InterpreterRuntimeError,
-} from "../interpreter/model.js"
+import { type AstNode, CoercionFunction, InterpreterRuntimeError } from "../interpreter/model.js"
 import { copyIn, type SafeObject } from "../tool-runtime.js"
 import {
   isSandboxValue,

packages/codemode/src/tool-runtime.ts

@@ -82,7 +82,6 @@ export type ToolDescription = {
 
 export type SafeObject = Record<string, unknown>
 
-const reservedNamespace = "$codemode"
 const defaultCatalogBudget = 2_000
 const defaultSearchLimit = 10
 const PositiveInt = Schema.Int.check(Schema.isGreaterThan(0))
@@ -326,15 +325,12 @@ export const copyOut = (value: unknown, undefinedAsNull = false): unknown => {
 const definitions = <R>(
   tools: HostTools<R>,
   path: ReadonlyArray<string> = [],
-): Array<{ path: string; definition: Definition<R> }> => {
-  const entries: Array<{ path: string; definition: Definition<R> }> = []
-  for (const [name, value] of Object.entries(tools)) {
+): Array<{ path: string; definition: Definition<R> }> =>
+  Object.entries(tools).flatMap(([name, value]) => {
     const next = [...path, name]
-    if (isDefinition(value)) entries.push({ path: next.join("."), definition: value })
-    else if (typeof value !== "function") entries.push(...definitions(value, next))
-  }
-  return entries
-}
+    if (isDefinition(value)) return [{ path: next.join("."), definition: value }]
+    return typeof value === "function" ? [] : definitions(value, next)
+  })
 
 const describeDefinition = <R>(path: string, definition: Definition<R>): ToolDescription => ({
   path,
@@ -349,9 +345,6 @@ const visibleDefinitions = <R>(tools: HostTools<R>) =>
     description: describeDefinition(path, definition),
   }))
 
-export const catalog = <R>(tools: HostTools<R>): ReadonlyArray<ToolDescription> =>
-  visibleDefinitions(tools).map(({ description }) => description)
-
 export type DiscoveryPlan = {
   readonly catalog: ReadonlyArray<ToolDescription>
   readonly instructions: string
@@ -458,7 +451,12 @@ const makeSearchTool = (searchIndex: ReadonlyArray<SearchEntry>): Definition =>
     }),
 })
 
-const searchDescription = describeDefinition(`${reservedNamespace}.search`, makeSearchTool([]))
+// The built-in `search` is a synchronous global function, not a tool-tree entry, so its
+// advertised signature is rendered by hand instead of through `describeDefinition`.
+const searchSignature = (() => {
+  const definition = makeSearchTool([])
+  return `search(input: ${inputTypeScript(definition, true)}): ${outputTypeScript(definition, true)}`
+})()
 
 const catalogLine = (tool: ToolDescription) => {
   // Keep the tool description concise; the full schema documentation remains in the signature.
@@ -485,12 +483,6 @@ const toSearchEntry = <R>(path: string, definition: Definition<R>, description:
 export const searchIndex = <R>(tools: HostTools<R>): ReadonlyArray<SearchEntry> =>
   visibleDefinitions(tools).map(({ path, definition, description }) => toSearchEntry(path, definition, description))
 
-export const assertValidTools = <R>(tools: HostTools<R>): void => {
-  if (Object.hasOwn(tools, reservedNamespace)) {
-    throw new Error(`Tool namespace '${reservedNamespace}' is reserved for CodeMode discovery tools.`)
-  }
-}
-
 /**
  * Budgeted catalog: every namespace is always listed with its tool count; full call
  * signatures are inlined against the `catalogBudget` (estimated tokens,
@@ -563,8 +555,8 @@ export const prepare = <R>(tools: HostTools<R>, catalogBudget = defaultCatalogBu
     empty
       ? "This is a restricted JavaScript language for calling tools, not a general-purpose runtime."
       : complete
-        ? "This is a restricted JavaScript language for calling tools, not a general-purpose runtime. Inside the confined interpreter, `tools` contains the Code Mode tools listed below and internal runtime tools; surrounding agent tools are not available."
-        : "This is a restricted JavaScript language for calling tools, not a general-purpose runtime. Inside the confined interpreter, `tools` contains the Code Mode tools listed or searchable below and internal runtime tools; surrounding agent tools are not available.",
+        ? "This is a restricted JavaScript language for calling tools, not a general-purpose runtime. Inside the confined interpreter, `tools` contains the Code Mode tools listed below; surrounding agent tools are not available."
+        : "This is a restricted JavaScript language for calling tools, not a general-purpose runtime. Inside the confined interpreter, `tools` contains the Code Mode tools listed or searchable below; surrounding agent tools are not available.",
     ...(empty
       ? []
       : ["Do not infer or normalize tool names; use only exact signatures shown below or returned by search."]),
@@ -585,7 +577,7 @@ export const prepare = <R>(tools: HostTools<R>, catalogBudget = defaultCatalogBu
               "3. Return only the fields you need from structured results; narrow unknown results before reading fields, and avoid returning large raw payloads.",
             ]
           : [
-              '1. If needed, discover tools: `return await tools.$codemode.search({ query: "<intent + key nouns>" })`.',
+              '1. If needed, discover tools with the built-in search function: `return search({ query: "<intent + key nouns>" })`.',
               "2. In the next execution, copy a returned path exactly, call it, and return only the needed fields.",
             ]),
       ]
@@ -597,8 +589,8 @@ export const prepare = <R>(tools: HostTools<R>, catalogBudget = defaultCatalogBu
         "## Rules",
         "",
         complete
-          ? "- Only Code Mode tools listed here and internal runtime tools are available; surrounding agent tools are not implicitly exposed."
-          : "- Only Code Mode tools listed here or returned by `tools.$codemode.search` and internal runtime tools are available; surrounding agent tools are not implicitly exposed.",
+          ? "- Only Code Mode tools listed here are available; surrounding agent tools are not implicitly exposed."
+          : "- Only Code Mode tools listed here or returned by the built-in `search` function are available; surrounding agent tools are not implicitly exposed.",
         "- Filter, aggregate, and transform collections in code - never return them raw or call a tool per item across messages.",
         "- A result typed `Promise<unknown>` may be structured data or text. Before reading fields, check that it is a non-null object and not an array; otherwise handle the returned text or primitive directly.",
         '- Run independent calls in parallel: `await Promise.all(items.map((item) => tools.<namespace>.<tool>(item)))`, or use `tools.<namespace>["tool-name"](item)` when the listed signature uses bracket notation.',
@@ -607,7 +599,7 @@ export const prepare = <R>(tools: HostTools<R>, catalogBudget = defaultCatalogBu
         ...(complete
           ? []
           : [
-              '- Browse one namespace: `await tools.$codemode.search({ query: "", namespace: "<name>" })`.',
+              '- Browse one namespace: `search({ query: "", namespace: "<name>" })`.',
               "- If search returns `next`, repeat the same search with `offset: next.offset`.",
             ]),
       ]
@@ -617,7 +609,7 @@ export const prepare = <R>(tools: HostTools<R>, catalogBudget = defaultCatalogBu
     "## Language",
     "",
     "Use common JavaScript data operations, functions, control flow, selected standard-library methods, and awaited tool calls. Built-ins include Date, RegExp, Map, Set, URL, URLSearchParams, and URI encoding helpers.",
-    "Modules/imports, classes, generators, timers, fetch, eval, prototype access, unlisted methods, and promise chaining are unavailable. Use Code Mode tools for external operations. Use await with try/catch.",
+    "Modules/imports, classes, generators, timers, fetch, eval, prototype access, and unlisted methods are unavailable. Use Code Mode tools for external operations. Use await with try/catch.",
     "Prefer explicit `return`; otherwise only the final top-level expression becomes the result.",
     "Dates and URLs serialize to strings at data boundaries; Map/Set/RegExp/URLSearchParams serialize to `{}`.",
   ]
@@ -629,7 +621,7 @@ export const prepare = <R>(tools: HostTools<R>, catalogBudget = defaultCatalogBu
     toolSection.push(
       complete
         ? "## Available tools (COMPLETE list - every tool is shown below with its full call signature)"
-        : `## Available tools (PARTIAL - ${totalShown} of ${described.length} shown; find the rest with tools.$codemode.search)`,
+        : `## Available tools (PARTIAL - ${totalShown} of ${described.length} shown; find the rest with search(...))`,
       "",
     )
     for (const [namespace, group] of ordered) {
@@ -647,7 +639,7 @@ export const prepare = <R>(tools: HostTools<R>, catalogBudget = defaultCatalogBu
       for (const tool of group) if (picked.has(tool)) toolSection.push(catalogLine(tool))
     }
     if (!complete) {
-      toolSection.push("", "Search returns complete callable signatures:", `- ${searchDescription.signature}`)
+      toolSection.push("", "Search returns complete callable signatures:", `- ${searchSignature}`)
     }
   }
 
@@ -676,7 +668,7 @@ const namespaceKeys = <R>(tools: HostTools<R>, path: ReadonlyArray<string>): Rea
       !Object.hasOwn(value, segment)
     ) {
       throw new ToolRuntimeError("UnknownTool", `Unknown tool namespace '${path.join(".")}'.`, [
-        "Object.keys(tools) lists the available namespaces; tools.$codemode.search({ query }) finds described tools.",
+        "Object.keys(tools) lists the available namespaces; search({ query }) finds described tools.",
       ])
     }
     value = value[segment] as HostTool<R> | Definition<R> | HostTools<R>
@@ -696,7 +688,7 @@ const resolve = <R>(tools: HostTools<R>, path: ReadonlyArray<string>): HostTool<
       !Object.hasOwn(value, segment)
     ) {
       throw new ToolRuntimeError("UnknownTool", `Unknown tool '${path.join(".")}'.`, [
-        "Use tools.$codemode.search({ query }) to find available described tools.",
+        "Use search({ query }) to find available described tools.",
       ])
     }
     value = value[segment] as HostTool<R> | Definition<R> | HostTools<R>
@@ -713,6 +705,11 @@ export type ToolRuntime<R = never> = {
   readonly root: ToolReference
   readonly calls: Array<ToolCall>
   readonly invoke: (path: ReadonlyArray<string>, args: Array<unknown>) => Effect.Effect<unknown, unknown, R>
+  /**
+   * The built-in `search` global: a synchronous discovery call that shares the tool
+   * admission pipeline (budget, audit, hooks) without living in the `tools` tree.
+   */
+  readonly search: (args: Array<unknown>) => Effect.Effect<unknown, unknown, R>
   /** Enumerable namespace/tool names at one node of the callable tool tree; see `namespaceKeys`. */
   readonly keys: (path: ReadonlyArray<string>) => ReadonlyArray<string>
 }
@@ -725,10 +722,7 @@ export const make = <R>(
   hooks?: ToolCallHooks<R>,
 ): ToolRuntime<R> => {
   const calls: Array<ToolCall> = []
-  const callableTools = {
-    ...tools,
-    [reservedNamespace]: { search: makeSearchTool(searchIndex) },
-  }
+  const searchTool = makeSearchTool(searchIndex)
 
   // Wraps the settling portion of a tool call so onToolCallEnd observes success and failure
   // symmetrically. Interruption (e.g. the execution timeout) fires neither outcome.
@@ -764,52 +758,59 @@ export const make = <R>(
     calls.push(call)
   }
 
+  const recordAndObserve = (name: string, input: unknown) =>
+    Effect.sync(() => {
+      recordCall({ name })
+      return calls.length - 1
+    }).pipe(Effect.tap((index) => hooks?.onToolCallStart?.({ index, name, input }) ?? Effect.void))
+
+  const invokeDefinition = (name: string, tool: Definition<R>, externalArgs: Array<unknown>) =>
+    Effect.gen(function* () {
+      if (externalArgs.length !== 1)
+        throw new ToolRuntimeError("InvalidToolInput", `Tool '${name}' expects exactly one input object.`)
+      const input = yield* Effect.try({
+        try: () => decodeToolInput(tool, externalArgs[0]),
+        catch: (cause) =>
+          new ToolRuntimeError("InvalidToolInput", `Invalid input for tool '${name}': ${String(cause)}`),
+      })
+      const index = yield* recordAndObserve(name, input)
+      return yield* observeEnd(
+        Effect.gen(function* () {
+          const raw = yield* runHost(Effect.suspend(() => tool.run(input)))
+          const result = yield* Effect.try({
+            try: () => decodeToolOutput(tool, raw),
+            catch: () => new ToolRuntimeError("InvalidToolOutput", `Invalid output from tool '${name}'.`),
+          })
+          return yield* decodeOutput(result, name)
+        }),
+        { index, name, input },
+      )
+    })
+
   return {
     root: new ToolReference([]),
     calls,
-    keys: (path) => namespaceKeys(callableTools, path),
+    keys: (path) => namespaceKeys(tools, path),
+    search: (args) =>
+      Effect.suspend(() =>
+        invokeDefinition(
+          "search",
+          searchTool,
+          args.map((arg) => copyOut(copyIn(arg, "Arguments for tool 'search'"))),
+        ),
+      ),
     invoke: (path, args) =>
       Effect.gen(function* () {
         const name = path.join(".")
         const externalArgs = args.map((arg) => copyOut(copyIn(arg, `Arguments for tool '${name}'`)))
-        const call = { name }
-        const recordAndObserve = (input: unknown) =>
-          Effect.sync(() => {
-            recordCall(call)
-            return calls.length - 1
-          }).pipe(Effect.tap((index) => hooks?.onToolCallStart?.({ index, name, input }) ?? Effect.void))
-        const tool = resolve(callableTools, path)
-        let describedInput: unknown
-        if (isDefinition(tool)) {
-          if (externalArgs.length !== 1)
-            throw new ToolRuntimeError("InvalidToolInput", `Tool '${name}' expects exactly one input object.`)
-          describedInput = yield* Effect.try({
-            try: () => decodeToolInput(tool, externalArgs[0]),
-            catch: (cause) =>
-              new ToolRuntimeError("InvalidToolInput", `Invalid input for tool '${name}': ${String(cause)}`),
-          })
-        }
-        const input = isDefinition(tool) ? describedInput : externalArgs
-        const index = yield* recordAndObserve(input)
-        const currentCall = { index, name, input }
-        if (isDefinition(tool)) {
-          return yield* observeEnd(
-            Effect.gen(function* () {
-              const raw = yield* runHost(Effect.suspend(() => tool.run(describedInput)))
-              const result = yield* Effect.try({
-                try: () => decodeToolOutput(tool, raw),
-                catch: () => new ToolRuntimeError("InvalidToolOutput", `Invalid output from tool '${name}'.`),
-              })
-              return yield* decodeOutput(result, name)
-            }),
-            currentCall,
-          )
-        }
+        const tool = resolve(tools, path)
+        if (isDefinition(tool)) return yield* invokeDefinition(name, tool, externalArgs)
+        const index = yield* recordAndObserve(name, externalArgs)
         return yield* observeEnd(
           Effect.gen(function* () {
             return yield* decodeOutput(yield* runHost(Effect.suspend(() => tool(...externalArgs))), name)
           }),
-          currentCall,
+          { index, name, input: externalArgs },
         )
       }),
   }

packages/codemode/src/tool-schema.ts

@@ -23,7 +23,7 @@ const effectNumberSentinel = (schema: JsonSchema) =>
 const intersection = (members: ReadonlyArray<string>): string => {
   const concrete = members.filter((member) => member !== "unknown")
   if (concrete.length === 0) return "unknown"
-  if (concrete.length === 1) return concrete[0] ?? "unknown"
+  if (concrete.length === 1) return concrete[0]
   return concrete.map((member) => (member.includes(" | ") ? `(${member})` : member)).join(" & ")
 }
 

packages/codemode/sst-env.d.ts

@@ -0,0 +1,10 @@
+/* This file is auto-generated by SST. Do not edit. */
+/* tslint:disable */
+/* eslint-disable */
+/* deno-fmt-ignore-file */
+/* biome-ignore-all lint: auto-generated */
+
+/// <reference path="../../sst-env.d.ts" />
+
+import "sst"
+export {}

packages/codemode/test/codemode.test.ts

@@ -541,11 +541,11 @@ describe("CodeMode public contract", () => {
       "  - tools.orders.lookup(input: {\n  id: string,\n}): Promise<{\n  id: string,\n  status: string,\n}> // Look up an order by ID",
     )
     // A fully inlined catalog does not advertise search in the instructions...
-    expect(runtime.instructions()).not.toMatch(/\$codemode/)
+    expect(runtime.instructions()).not.toContain("search(")
 
-    // ...but the search tool stays registered, so a speculative call still works with the
+    // ...but the search built-in stays available, so a speculative call still works with the
     // same signature as the inline catalog.
-    const result = await Effect.runPromise(runtime.execute(`return await tools.$codemode.search({ query: "order" })`))
+    const result = await Effect.runPromise(runtime.execute(`return search({ query: "order" })`))
     expect(result.ok).toBe(true)
     if (result.ok) {
       expect(result.value).toStrictEqual({
@@ -583,9 +583,7 @@ describe("CodeMode public contract", () => {
       'tools.context7["resolve-library-id"](input: {\n  libraryName: string,\n}): Promise<string>',
     )
 
-    const search = await Effect.runPromise(
-      runtime.execute(`return await tools.$codemode.search({ query: "resolve library id" })`),
-    )
+    const search = await Effect.runPromise(runtime.execute(`return search({ query: "resolve library id" })`))
     expect(search.ok).toBe(true)
     if (search.ok) {
       expect(search.value).toStrictEqual({
@@ -608,7 +606,7 @@ describe("CodeMode public contract", () => {
     if (call.ok) expect(call.value).toBe("/resolved/TypeScript")
 
     const exact = await Effect.runPromise(
-      runtime.execute(`return await tools.$codemode.search({ query: 'tools.context7["resolve-library-id"]' })`),
+      runtime.execute(`return search({ query: 'tools.context7["resolve-library-id"]' })`),
     )
     expect(exact.ok).toBe(true)
     if (exact.ok) expect(exact.value).toMatchObject({ remaining: 0, next: null })
@@ -632,7 +630,7 @@ describe("CodeMode public contract", () => {
     expect(instructions).toContain("Do not infer or normalize tool names")
     expect(instructions).toContain("bracket notation and quotes are part of the path")
     expect(instructions).toContain("surrounding agent tools are not available")
-    expect(instructions).toContain("Only Code Mode tools listed here and internal runtime tools")
+    expect(instructions).toContain("Only Code Mode tools listed here are available")
     // Placeholders use generic namespace/tool/field names only - no fabricated real tools
     // and no real catalog tools cherry-picked into example lines.
     expect(instructions).toContain("`const result = await tools.<namespace>.<tool>(input)`")
@@ -651,15 +649,11 @@ describe("CodeMode public contract", () => {
     // PARTIAL: the workflow starts with search (with query-style guidance that is clearly
     // a query string, never a tool name) and the browse-namespace rule appears.
     expect(partial).toContain(
-      '1. If needed, discover tools: `return await tools.$codemode.search({ query: "<intent + key nouns>" })`.',
+      '1. If needed, discover tools with the built-in search function: `return search({ query: "<intent + key nouns>" })`.',
     )
     expect(partial).toContain("In the next execution, copy a returned path exactly")
-    expect(partial).toContain(
-      "Only Code Mode tools listed here or returned by `tools.$codemode.search` and internal runtime tools",
-    )
-    expect(partial).toContain(
-      '- Browse one namespace: `await tools.$codemode.search({ query: "", namespace: "<name>" })`.',
-    )
+    expect(partial).toContain("Only Code Mode tools listed here or returned by the built-in `search` function")
+    expect(partial).toContain('- Browse one namespace: `search({ query: "", namespace: "<name>" })`.')
     expect(partial).toContain("repeat the same search with `offset: next.offset`")
     expect(partial).toContain("  limit?: number,\n  offset?: number,")
     expect(partial).not.toContain("total_count")
@@ -672,9 +666,11 @@ describe("CodeMode public contract", () => {
     expect(instructions).toContain("not a general-purpose runtime")
     expect(instructions).not.toContain("Standard modern JavaScript works")
     expect(instructions).not.toContain("TypeScript type annotations")
-    for (const missing of ["Modules/imports", "classes", "generators", "fetch", "promise chaining"]) {
+    for (const missing of ["Modules/imports", "classes", "generators", "fetch"]) {
       expect(instructions).toContain(missing)
     }
+    expect(instructions).not.toContain("new Promise(...) are unavailable")
+    expect(instructions).not.toContain("promise chaining")
     expect(instructions).toContain("URL, URLSearchParams, and URI encoding helpers")
     expect(instructions).not.toContain("host globals")
     expect(instructions).toContain("Use Code Mode tools for external operations")
@@ -694,7 +690,7 @@ describe("CodeMode public contract", () => {
     expect(instructions).toContain("## Available tools")
     expect(instructions).not.toContain("## Workflow")
     expect(instructions).not.toContain("## Rules")
-    expect(instructions).not.toMatch(/\$codemode/)
+    expect(instructions).not.toContain("search(")
   })
 
   test("uses one ranked search returning complete definitions for large catalogs", async () => {
@@ -714,17 +710,15 @@ describe("CodeMode public contract", () => {
       tools: { thread: { uploadFile: upload, generateImage: generate }, orders: { lookup } },
       discovery: { catalogBudget: 0 },
     })
-    expect(runtime.instructions()).toContain(
-      "Available tools (PARTIAL - 0 of 3 shown; find the rest with tools.$codemode.search)",
-    )
+    expect(runtime.instructions()).toContain("Available tools (PARTIAL - 0 of 3 shown; find the rest with search(...))")
     expect(runtime.instructions()).toContain("- thread (2 tools, none shown)")
     expect(runtime.instructions()).toContain("- orders (1 tool, none shown)")
-    expect(runtime.instructions()).toMatch(/\$codemode\.search/)
+    expect(runtime.instructions()).toContain("Search returns complete callable signatures:\n- search(input: {")
     expect(runtime.instructions()).not.toMatch(/tools\.thread\.uploadFile\(input/)
 
     const result = await Effect.runPromise(
       runtime.execute(`
-      return await tools.$codemode.search({
+      return search({
         query: "send message attachment upload file to current Discord thread",
         limit: 2
       })
@@ -748,14 +742,14 @@ describe("CodeMode public contract", () => {
       remaining: 0,
       next: null,
     })
-    expect(result.toolCalls).toStrictEqual([{ name: "$codemode.search" }])
+    expect(result.toolCalls).toStrictEqual([{ name: "search" }])
 
     const variants = await Effect.runPromise(
       runtime.execute(`
-      return await Promise.all([
-        tools.$codemode.search({ query: "file" }),
-        tools.$codemode.search({ query: "image" })
-      ])
+      return [
+        search({ query: "file" }),
+        search({ query: "image" })
+      ]
     `),
     )
     expect(variants.ok).toBe(true)
@@ -767,12 +761,35 @@ describe("CodeMode public contract", () => {
         "tools.thread.generateImage",
       )
     }
+  })
 
-    const removed = await Effect.runPromise(
-      runtime.execute(`return await tools.$codemode.describe({ path: "thread.uploadFile" })`),
-    )
-    expect(removed.ok).toBe(false)
-    if (!removed.ok) expect(removed.error.kind).toBe("UnknownTool")
+  test("search is a counted tool call: it burns maxToolCalls and fires the hooks", async () => {
+    const started: Array<string> = []
+    const ended: Array<string> = []
+    const limited = CodeMode.make({
+      tools,
+      limits: { maxToolCalls: 1 },
+      onToolCallStart: (call) => Effect.sync(() => void started.push(call.name)),
+      onToolCallEnd: (call) => Effect.sync(() => void ended.push(`${call.name}:${call.outcome}`)),
+    })
+    const result = await Effect.runPromise(limited.execute(`search({}); return search({})`))
+    expect(result.ok).toBe(false)
+    if (!result.ok) expect(result.error.kind).toBe("ToolCallLimitExceeded")
+    expect(started).toEqual(["search"])
+    expect(ended).toEqual(["search:success"])
+  })
+
+  test("search is an opaque, shadowable global like other built-ins", async () => {
+    const runtime = CodeMode.make({ tools })
+    expect(await Effect.runPromise(runtime.execute(`return typeof search`))).toMatchObject({ value: "function" })
+    // A program-level declaration shadows the global, as JS module scope does.
+    const shadowed = await Effect.runPromise(runtime.execute(`const search = () => "local"; return search()`))
+    expect(shadowed.ok).toBe(true)
+    if (shadowed.ok) expect(shadowed.value).toBe("local")
+    // The reference itself cannot cross the data boundary.
+    const escaped = await Effect.runPromise(runtime.execute(`return { search }`))
+    expect(escaped.ok).toBe(false)
+    if (!escaped.ok) expect(escaped.error.kind).toBe("InvalidDataValue")
   })
 
   test("search defaults to 10 results and resolves exact tool paths", async () => {
@@ -789,7 +806,7 @@ describe("CodeMode public contract", () => {
       },
     })
 
-    const browse = await Effect.runPromise(runtime.execute(`return await tools.$codemode.search({})`))
+    const browse = await Effect.runPromise(runtime.execute(`return search({})`))
     expect(browse.ok).toBe(true)
     if (browse.ok) {
       const value = browse.value as {
@@ -803,9 +820,7 @@ describe("CodeMode public contract", () => {
     }
 
     for (const query of ["many.tool13", "tools.many.tool13"]) {
-      const exact = await Effect.runPromise(
-        runtime.execute(`return await tools.$codemode.search({ query: ${JSON.stringify(query)} })`),
-      )
+      const exact = await Effect.runPromise(runtime.execute(`return search({ query: ${JSON.stringify(query)} })`))
       expect(exact.ok).toBe(true)
       if (exact.ok) {
         expect(exact.value).toStrictEqual({
@@ -839,9 +854,7 @@ describe("CodeMode public contract", () => {
     })
 
     // Empty query + namespace browses just that namespace, alphabetical by path.
-    const browse = await Effect.runPromise(
-      runtime.execute(`return await tools.$codemode.search({ query: "", namespace: "github" })`),
-    )
+    const browse = await Effect.runPromise(runtime.execute(`return search({ query: "", namespace: "github" })`))
     expect(browse.ok).toBe(true)
     if (browse.ok) {
       const value = browse.value as { items: Array<{ path: string }>; remaining: number }
@@ -853,9 +866,7 @@ describe("CodeMode public contract", () => {
     }
 
     // A query + namespace ranks within that namespace only.
-    const scoped = await Effect.runPromise(
-      runtime.execute(`return await tools.$codemode.search({ query: "issues", namespace: "linear" })`),
-    )
+    const scoped = await Effect.runPromise(runtime.execute(`return search({ query: "issues", namespace: "linear" })`))
     expect(scoped.ok).toBe(true)
     if (scoped.ok) {
       const value = scoped.value as { items: Array<{ path: string }>; remaining: number }
@@ -863,9 +874,7 @@ describe("CodeMode public contract", () => {
       expect(value.items[0]?.path).toBe("tools.linear.list_issues")
     }
 
-    const invalid = await Effect.runPromise(
-      runtime.execute(`return await tools.$codemode.search({ query: "issues", namespace: 7 })`),
-    )
+    const invalid = await Effect.runPromise(runtime.execute(`return search({ query: "issues", namespace: 7 })`))
     expect(invalid.ok).toBe(false)
     if (!invalid.ok) expect(invalid.error.kind).toBe("InvalidToolInput")
   })
@@ -890,9 +899,7 @@ describe("CodeMode public contract", () => {
 
     // "attachment" appears in neither path nor description - only in the input schema's
     // property names, which the searchable text includes.
-    const byParameter = await Effect.runPromise(
-      runtime.execute(`return await tools.$codemode.search({ query: "attachment" })`),
-    )
+    const byParameter = await Effect.runPromise(runtime.execute(`return search({ query: "attachment" })`))
     expect(byParameter.ok).toBe(true)
     if (byParameter.ok) {
       const value = byParameter.value as { items: Array<{ path: string }>; remaining: number }
@@ -901,9 +908,7 @@ describe("CodeMode public contract", () => {
     }
 
     // Substring matching: a partial word ("docum") still hits the description.
-    const bySubstring = await Effect.runPromise(
-      runtime.execute(`return await tools.$codemode.search({ query: "docum" })`),
-    )
+    const bySubstring = await Effect.runPromise(runtime.execute(`return search({ query: "docum" })`))
     expect(bySubstring.ok).toBe(true)
     if (bySubstring.ok) {
       const value = bySubstring.value as { items: Array<{ path: string }>; remaining: number }
@@ -930,9 +935,7 @@ describe("CodeMode public contract", () => {
     })
 
     // "issues" still finds the singular-only tool (term OR singular(term) per field)...
-    const plural = await Effect.runPromise(
-      runtime.execute(`return await tools.$codemode.search({ query: "issues", namespace: "tracker" })`),
-    )
+    const plural = await Effect.runPromise(runtime.execute(`return search({ query: "issues", namespace: "tracker" })`))
     expect(plural.ok).toBe(true)
     if (plural.ok) {
       const value = plural.value as { items: Array<{ path: string }>; remaining: number }
@@ -941,7 +944,7 @@ describe("CodeMode public contract", () => {
     }
 
     // ...while a true "issues" path match still outranks the singular-only description match.
-    const ranked = await Effect.runPromise(runtime.execute(`return await tools.$codemode.search({ query: "issues" })`))
+    const ranked = await Effect.runPromise(runtime.execute(`return search({ query: "issues" })`))
     expect(ranked.ok).toBe(true)
     if (ranked.ok) {
       const value = ranked.value as { items: Array<{ path: string }>; remaining: number }
@@ -968,7 +971,7 @@ describe("CodeMode public contract", () => {
         alpha: { beta: simple("Middle"), aardvark: simple("First") },
       },
     })
-    const browse = await Effect.runPromise(runtime.execute(`return await tools.$codemode.search({})`))
+    const browse = await Effect.runPromise(runtime.execute(`return search({})`))
     expect(browse.ok).toBe(true)
     if (browse.ok) {
       const value = browse.value as { items: Array<{ path: string }>; remaining: number; next: unknown }
@@ -981,9 +984,7 @@ describe("CodeMode public contract", () => {
       expect(value.next).toBeNull()
     }
 
-    const middle = await Effect.runPromise(
-      runtime.execute(`return await tools.$codemode.search({ limit: 1, offset: 1 })`),
-    )
+    const middle = await Effect.runPromise(runtime.execute(`return search({ limit: 1, offset: 1 })`))
     expect(middle.ok).toBe(true)
     if (middle.ok) {
       expect(middle.value).toMatchObject({
@@ -993,9 +994,7 @@ describe("CodeMode public contract", () => {
       })
     }
 
-    const exhausted = await Effect.runPromise(
-      runtime.execute(`return await tools.$codemode.search({ limit: 1, offset: 3 })`),
-    )
+    const exhausted = await Effect.runPromise(runtime.execute(`return search({ limit: 1, offset: 3 })`))
     expect(exhausted.ok).toBe(true)
     if (exhausted.ok) expect(exhausted.value).toStrictEqual({ items: [], remaining: 0, next: null })
   })
@@ -1026,16 +1025,14 @@ describe("CodeMode public contract", () => {
     })
 
     const instructions = runtime.instructions()
-    expect(instructions).toContain(
-      "Available tools (PARTIAL - 2 of 3 shown; find the rest with tools.$codemode.search)",
-    )
+    expect(instructions).toContain("Available tools (PARTIAL - 2 of 3 shown; find the rest with search(...))")
     expect(instructions).toContain("- alpha (2 tools, 1 shown)")
     expect(instructions).toContain("  - tools.alpha.cheap(input: {\n  q: string,\n}): Promise<string> // Cheap")
     expect(instructions).not.toContain("tools.alpha.expensive(")
     // Fully shown namespaces read cleanly (no "shown" annotation).
     expect(instructions).toContain("- beta (1 tool)")
     expect(instructions).toContain("  - tools.beta.cheap(input: {\n  q: string,\n}): Promise<string> // Cheap")
-    expect(instructions).toMatch(/\$codemode\.search/)
+    expect(instructions).toContain("Search returns complete callable signatures:\n- search(input: {")
   })
 
   test("charges inline JSDoc against the catalog token budget", () => {
@@ -1056,9 +1053,7 @@ describe("CodeMode public contract", () => {
     })
 
     expect(runtime.catalog()[0]?.signature).toContain("/** A detailed identifier description.")
-    expect(runtime.instructions()).toContain(
-      "Available tools (PARTIAL - 0 of 1 shown; find the rest with tools.$codemode.search)",
-    )
+    expect(runtime.instructions()).toContain("Available tools (PARTIAL - 0 of 1 shown; find the rest with search(...))")
     expect(runtime.instructions()).not.toContain("tools.records.lookup(input:")
   })
 
@@ -1136,7 +1131,7 @@ describe("CodeMode public contract", () => {
       CodeMode.make({
         tools,
         discovery: { catalogBudget: 0 },
-      }).execute(`return await tools.$codemode.search({ query: "order", limit: 0.5 })`),
+      }).execute(`return search({ query: "order", limit: 0.5 })`),
     )
     expect(result.ok).toBe(false)
     if (result.ok) return
@@ -1144,9 +1139,7 @@ describe("CodeMode public contract", () => {
 
     for (const offset of [-1, 0.5, Number.MAX_SAFE_INTEGER + 1, "1"]) {
       const invalidOffset = await Effect.runPromise(
-        CodeMode.make({ tools }).execute(
-          `return await tools.$codemode.search({ query: "order", offset: ${JSON.stringify(offset)} })`,
-        ),
+        CodeMode.make({ tools }).execute(`return search({ query: "order", offset: ${JSON.stringify(offset)} })`),
       )
       expect(invalidOffset.ok).toBe(false)
       if (!invalidOffset.ok) expect(invalidOffset.error.kind).toBe("InvalidToolInput")
@@ -1197,8 +1190,4 @@ describe("CodeMode public contract", () => {
     }
     expect(elapsedMs).toBeLessThan(3_000)
   })
-
-  test("reserves the discovery namespace", () => {
-    expect(() => CodeMode.make({ tools: { $codemode: { lookup } } })).toThrow(/reserved for CodeMode discovery tools/)
-  })
 })

packages/codemode/test/enumeration.test.ts

@@ -41,7 +41,7 @@ describe("Object.keys over tool references", () => {
       const namespaces = Object.keys(tools)
       return { namespaces, count: namespaces.length }
     `),
-    ).toEqual({ namespaces: ["github", "memory", "playwright", "$codemode"], count: 4 })
+    ).toEqual({ namespaces: ["github", "memory", "playwright"], count: 3 })
   })
 
   test("enumerates tool names at a nested namespace", async () => {
@@ -52,8 +52,8 @@ describe("Object.keys over tool references", () => {
     expect(await value(`return Object.keys(tools.github.list_issues)`)).toEqual([])
   })
 
-  test("the internal discovery namespace enumerates its callable surface", async () => {
-    expect(await value(`return Object.keys(tools.$codemode)`)).toEqual(["search"])
+  test("search is a global built-in function", async () => {
+    expect(await value(`return typeof search`)).toBe("function")
   })
 
   test("an unknown namespace is an UnknownTool error pointing at the discovery idioms", async () => {
@@ -68,7 +68,7 @@ describe("Object.keys over tool references", () => {
       const failure = await error(`return Object.${method}(tools)`)
       expect(failure.kind).toBe("InvalidDataValue")
       expect(failure.message).toContain(
-        `Object.${method}(...) cannot read tool references: they are not plain data. Use Object.keys(tools) for names, or tools.$codemode.search({ query }) for signatures.`,
+        `Object.${method}(...) cannot read tool references: they are not plain data. Use Object.keys(tools) for names, or search({ query }) for signatures.`,
       )
     }
     const nested = await error(`return Object.entries(tools.github)`)
@@ -146,7 +146,7 @@ describe("for...in", () => {
       }
       return names
     `),
-    ).toEqual(["github.list_issues", "github.get_issue", "memory.search", "playwright.navigate", "$codemode.search"])
+    ).toEqual(["github.list_issues", "github.get_issue", "memory.search", "playwright.navigate"])
   })
 
   test("unsupported values fail with a hint at for...of and Object.keys", async () => {

packages/codemode/test/openapi.test.ts

@@ -377,7 +377,7 @@ describe("OpenAPI.fromSpec", () => {
       runtime
         .execute(
           `
-        return await tools.$codemode.search({ query: "global health", namespace: "opencode", limit: 1 })
+        return search({ query: "global health", namespace: "opencode", limit: 1 })
       `,
         )
         .pipe(Effect.provide(layer)),

packages/codemode/test/promise-test262.test.ts

@@ -16,8 +16,7 @@ import { describe, expect, test } from "bun:test"
 import { Effect } from "effect"
 import { CodeMode } from "../src/index.js"
 
-const execute = (code: string) =>
-  Effect.runPromise(CodeMode.execute({ code, tools: {}, limits: { timeoutMs: 1_000 } }))
+const execute = (code: string) => Effect.runPromise(CodeMode.execute({ code, tools: {}, limits: { timeoutMs: 1_000 } }))
 
 const value = async (code: string) => {
   const result = await execute(code)
@@ -450,7 +449,10 @@ describe("Test262 async functions and await", () => {
         const promises = [declaration(), expression(), arrow()]
         return [promises.map((item) => item instanceof Promise), await Promise.all(promises)]
       `),
-    ).toEqual([[true, true, true], [1, 2, 3]])
+    ).toEqual([
+      [true, true, true],
+      [1, 2, 3],
+    ])
   })
 
   test("async bodies adopt returns and reject throws before and after await", async () => {
@@ -479,13 +481,7 @@ describe("Test262 async functions and await", () => {
           await observe(throwsAfter()),
         ]
       `),
-    ).toEqual([
-      ["body"],
-      ["fulfilled", 42],
-      ["fulfilled", 43],
-      ["rejected", 1],
-      ["rejected", 2],
-    ])
+    ).toEqual([["body"], ["fulfilled", 42], ["fulfilled", 43], ["rejected", 1], ["rejected", 2]])
   })
 
   test("default-parameter throws reject instead of escaping the call", async () => {
@@ -577,13 +573,14 @@ describe("Test262 async functions and await", () => {
 })
 
 describe("Test262 expected Promise conformance", () => {
-  for (const name of ["all", "allSettled", "race"] as const) {
-    test.failing(`Promise.${name} rejects invalid input with TypeError`, async () => {
+  for (const name of ["all", "allSettled", "race", "any"] as const) {
+    test(`Promise.${name} rejects invalid input with TypeError`, async () => {
       // Sources:
       // test/built-ins/Promise/all/S25.4.4.1_A3.1_T1.js
       // test/built-ins/Promise/all/S25.4.4.1_A3.1_T2.js
       // test/built-ins/Promise/allSettled/iter-arg-is-number-reject.js
       // test/built-ins/Promise/race/iter-arg-is-number-reject.js
+      // test/built-ins/Promise/any/iter-arg-is-number-reject.js
       expect(
         await value(`
           try {
@@ -599,7 +596,7 @@ describe("Test262 expected Promise conformance", () => {
     })
   }
 
-  test.failing("Promise.all consumes sparse positions as undefined", async () => {
+  test("Promise.all consumes sparse positions as undefined", async () => {
     // Source: test/built-ins/Array/from/from-array.js (array iterator hole behavior)
     expect(
       await value(`
@@ -611,7 +608,7 @@ describe("Test262 expected Promise conformance", () => {
     ).toEqual([2, true, 1])
   })
 
-  test.failing("Promise.allSettled consumes sparse positions as undefined", async () => {
+  test("Promise.allSettled consumes sparse positions as undefined", async () => {
     // Source: test/built-ins/Array/from/from-array.js (array iterator hole behavior)
     expect(
       await value(`
@@ -623,7 +620,7 @@ describe("Test262 expected Promise conformance", () => {
     ).toEqual([2, "fulfilled", true, { status: "fulfilled", value: 1 }])
   })
 
-  test.failing("Promise.race consumes a sparse first position as undefined", async () => {
+  test("Promise.race consumes a sparse first position as undefined", async () => {
     // Source: test/built-ins/Array/from/from-array.js (array iterator hole behavior)
     expect(
       await value(`
@@ -634,7 +631,18 @@ describe("Test262 expected Promise conformance", () => {
     ).toBe(true)
   })
 
-  test.failing("Promise.all settles after reactions attached to its inputs", async () => {
+  test("Promise.any consumes a sparse first position as an undefined fulfillment", async () => {
+    // Source: test/built-ins/Array/from/from-array.js (array iterator hole behavior)
+    expect(
+      await value(`
+        const input = []
+        input[1] = Promise.reject("loses")
+        return (await Promise.any(input)) === undefined
+      `),
+    ).toBe(true)
+  })
+
+  test("Promise.all settles after reactions attached to its inputs", async () => {
     // Sources:
     // test/built-ins/Promise/all/S25.4.4.1_A7.2_T1.js
     // test/built-ins/Promise/all/S25.4.4.1_A8.1_T1.js
@@ -653,7 +661,7 @@ describe("Test262 expected Promise conformance", () => {
     ).toEqual([1, 2, 3, 4, 5])
   })
 
-  test.failing("Promise.allSettled settles after reactions attached to its inputs", async () => {
+  test("Promise.allSettled settles after reactions attached to its inputs", async () => {
     // Sources:
     // test/built-ins/Promise/allSettled/resolved-sequence.js
     // test/built-ins/Promise/allSettled/resolved-sequence-extra-ticks.js
@@ -674,7 +682,7 @@ describe("Test262 expected Promise conformance", () => {
     ).toEqual([1, 2, 3, 4, 5])
   })
 
-  test.failing("Promise.race settles in a reaction after its winning input", async () => {
+  test("Promise.race settles in a reaction after its winning input", async () => {
     // Sources:
     // test/built-ins/Promise/race/S25.4.4.3_A6.1_T1.js
     // test/built-ins/Promise/race/resolved-sequence-extra-ticks.js
@@ -692,7 +700,7 @@ describe("Test262 expected Promise conformance", () => {
     ).toEqual([1, 2, 3, 4, 5])
   })
 
-  test.failing("then reactions route and propagate fulfillment and rejection", async () => {
+  test("then reactions route and propagate fulfillment and rejection", async () => {
     // Sources:
     // test/built-ins/Promise/prototype/then/prfm-fulfilled.js
     // test/built-ins/Promise/prototype/then/prfm-rejected.js
@@ -726,7 +734,7 @@ describe("Test262 expected Promise conformance", () => {
     ])
   })
 
-  test.failing("then reactions preserve breadth-first queue order", async () => {
+  test("then reactions preserve breadth-first queue order", async () => {
     // Source: test/built-ins/Promise/prototype/then/S25.4.4_A1.1_T1.js
     expect(
       await value(`
@@ -741,7 +749,7 @@ describe("Test262 expected Promise conformance", () => {
     ).toEqual([1, 2, 3, 4, 5, 6, 7, 8])
   })
 
-  test.failing("then rejects direct self-resolution for fulfilled and rejected sources", async () => {
+  test("then rejects direct self-resolution for fulfilled and rejected sources", async () => {
     // Sources:
     // test/built-ins/Promise/prototype/then/resolve-settled-fulfilled-self.js
     // test/built-ins/Promise/prototype/then/resolve-settled-rejected-self.js
@@ -761,7 +769,7 @@ describe("Test262 expected Promise conformance", () => {
     ).toEqual(["TypeError", "TypeError"])
   })
 
-  test.failing("catch delegates rejection handling and preserves fulfillment", async () => {
+  test("catch delegates rejection handling and preserves fulfillment", async () => {
     // Sources:
     // test/built-ins/Promise/prototype/catch/S25.4.5.1_A2.1_T1.js
     // test/built-ins/Promise/prototype/catch/S25.4.5.1_A3.1_T1.js
@@ -776,7 +784,7 @@ describe("Test262 expected Promise conformance", () => {
     ).toEqual([1, 4])
   })
 
-  test.failing("finally preserves or replaces the original settlement", async () => {
+  test("finally preserves or replaces the original settlement", async () => {
     // Sources:
     // test/built-ins/Promise/prototype/finally/resolution-value-no-override.js
     // test/built-ins/Promise/prototype/finally/rejection-reason-no-fulfill.js
@@ -799,7 +807,109 @@ describe("Test262 expected Promise conformance", () => {
     ])
   })
 
-  test.failing("await always resumes in a later reaction and interleaves async functions", async () => {
+  test("then ignores non-callable handlers", async () => {
+    // Sources:
+    // test/built-ins/Promise/prototype/then/S25.4.5.3_A4.1_T1.js
+    // test/built-ins/Promise/prototype/then/S25.4.5.3_A4.1_T2.js
+    // test/built-ins/Promise/prototype/then/S25.4.5.3_A5.1_T1.js
+    // test/built-ins/Promise/prototype/then/S25.4.5.3_A5.2_T1.js
+    // (adapted: only non-callable handlers are probed; callables that are not plain
+    //  functions, such as tool references, intentionally throw in CodeMode)
+    expect(
+      await value(`
+        const observe = async (promise) => {
+          try { return ["fulfilled", await promise] } catch (reason) { return ["rejected", reason] }
+        }
+        return await Promise.all([
+          observe(Promise.resolve(1).then(2)),
+          observe(Promise.resolve(4).then(null, null)),
+          observe(Promise.resolve(5).then({}, "x")),
+          observe(Promise.reject(3).then(null, "x")),
+          observe(Promise.reject(6).then(7, {})),
+        ])
+      `),
+    ).toEqual([
+      ["fulfilled", 1],
+      ["fulfilled", 4],
+      ["fulfilled", 5],
+      ["rejected", 3],
+      ["rejected", 6],
+    ])
+  })
+
+  test("finally waits for a returned promise and preserves or replaces settlement", async () => {
+    // Sources:
+    // test/built-ins/Promise/prototype/finally/resolved-observable-then-calls.js
+    // test/built-ins/Promise/prototype/finally/rejected-observable-then-calls.js
+    // test/built-ins/Promise/prototype/finally/resolution-value-no-override.js
+    expect(
+      await value(`
+        const observe = async (promise) => {
+          try { return ["fulfilled", await promise] } catch (reason) { return ["rejected", reason] }
+        }
+        const order = []
+        const cleanup = async () => {
+          await Promise.resolve()
+          order.push("cleanup")
+        }
+        const settled = await Promise.resolve("kept").finally(() => cleanup())
+        order.push("settled:" + settled)
+        return [
+          await observe(Promise.resolve(1).finally(() => Promise.resolve(99))),
+          order,
+          await observe(Promise.resolve(2).finally(() => Promise.reject(3))),
+          await observe(Promise.reject(4).finally(() => Promise.resolve(99))),
+        ]
+      `),
+    ).toEqual([
+      ["fulfilled", 1],
+      ["cleanup", "settled:kept"],
+      ["rejected", 3],
+      ["rejected", 4],
+    ])
+  })
+
+  test("then adopts a returned rejected promise", async () => {
+    // Sources:
+    // test/built-ins/Promise/prototype/then/rxn-handler-fulfilled-return-abrupt.js
+    // test/built-ins/Promise/resolve/resolve-promise.js
+    // (adapted: the fulfillment handler returns an already-rejected promise instead of
+    //  throwing, and the rejection handler recovers with a fulfilled promise)
+    expect(
+      await value(`
+        const observe = async (promise) => {
+          try { return ["fulfilled", await promise] } catch (reason) { return ["rejected", reason] }
+        }
+        return await Promise.all([
+          observe(Promise.resolve(1).then(() => Promise.reject("bad"))),
+          observe(Promise.reject(2).then(undefined, () => Promise.resolve("ok"))),
+        ])
+      `),
+    ).toEqual([
+      ["rejected", "bad"],
+      ["fulfilled", "ok"],
+    ])
+  })
+
+  test("independent reactions on one source each observe the same settlement", async () => {
+    // Source: test/built-ins/Promise/prototype/then/S25.4.4_A2.1_T1.js
+    // (adapted: the multiple-reactions family is asserted through the values every
+    //  reaction returns instead of a shared completion counter)
+    expect(
+      await value(`
+        const fulfilled = Promise.resolve(7)
+        const rejected = Promise.reject(8)
+        return await Promise.all([
+          fulfilled.then((value) => "first:" + value),
+          fulfilled.then((value) => "second:" + value),
+          rejected.catch((reason) => "first:" + reason),
+          rejected.catch((reason) => "second:" + reason),
+        ])
+      `),
+    ).toEqual(["first:7", "second:7", "first:8", "second:8"])
+  })
+
+  test("await always resumes in a later reaction and interleaves async functions", async () => {
     // Sources:
     // test/language/expressions/await/async-await-interleaved.js
     // test/language/expressions/await/await-non-promise.js
@@ -814,7 +924,7 @@ describe("Test262 expected Promise conformance", () => {
     ).toEqual(["first:1", "second:1", "first:2", "second:2"])
   })
 
-  test.failing("an async function rejects when it resolves with its own promise", async () => {
+  test("an async function rejects when it resolves with its own promise", async () => {
     // Adapted from the self-resolution requirement represented by:
     // test/built-ins/Promise/resolve-self.js
     // test/built-ins/Promise/resolve/S25.4.4.5_A4.1_T1.js
@@ -904,3 +1014,410 @@ describe("Test262 expected Promise conformance", () => {
     ).toBe(true)
   })
 })
+
+describe("Test262 Promise.any", () => {
+  test("is a callable static that returns a promise", async () => {
+    // Sources:
+    // test/built-ins/Promise/any/is-function.js
+    // test/built-ins/Promise/any/returns-promise.js
+    expect(
+      await value(`
+        const promise = Promise.any([1])
+        return [typeof Promise.any, promise instanceof Promise, await promise]
+      `),
+    ).toEqual(["function", true, 1])
+  })
+
+  test("fulfills with the first fulfilled member, ignoring rejections", async () => {
+    // Sources:
+    // test/built-ins/Promise/any/resolved-sequence-mixed.js
+    // test/built-ins/Promise/any/resolved-sequence-with-rejections.js
+    // test/built-ins/Promise/any/reject-ignored-immed.js
+    expect(
+      await value(`
+        return [
+          await Promise.any([Promise.reject("a"), Promise.resolve(1), Promise.resolve(2)]),
+          await Promise.any([Promise.reject("a"), "plain", Promise.reject("b")]),
+        ]
+      `),
+    ).toEqual([1, "plain"])
+  })
+
+  test("a fulfillment wins over a later rejection of another member", async () => {
+    // Sources:
+    // test/built-ins/Promise/any/resolve-ignores-late-rejection.js
+    // test/built-ins/Promise/any/resolve-ignores-late-rejection-deferred.js
+    expect(
+      await value(`
+        let rejectLate
+        const late = new Promise((_, reject) => { rejectLate = reject })
+        const result = await Promise.any([late, Promise.resolve("won")])
+        rejectLate("too late")
+        return result
+      `),
+    ).toBe("won")
+  })
+
+  test("rejects with an AggregateError carrying the reasons in input order", async () => {
+    // Sources:
+    // test/built-ins/Promise/any/reject-all-mixed.js
+    // test/built-ins/Promise/any/reject-immed.js
+    // test/built-ins/Promise/any/reject-deferred.js
+    expect(
+      await value(`
+        let rejectLate
+        const late = new Promise((_, reject) => { rejectLate = reject })
+        const aggregate = Promise.any([Promise.reject("first"), late, Promise.reject("third")])
+        rejectLate("second")
+        try {
+          await aggregate
+          return "fulfilled"
+        } catch (error) {
+          return {
+            isAggregate: error instanceof AggregateError,
+            isError: error instanceof Error,
+            name: error.name,
+            message: error.message,
+            errors: error.errors,
+          }
+        }
+      `),
+    ).toEqual({
+      isAggregate: true,
+      isError: true,
+      name: "AggregateError",
+      message: "All promises were rejected",
+      errors: ["first", "second", "third"],
+    })
+  })
+
+  test("rejects an empty input with an empty AggregateError", async () => {
+    // Source: test/built-ins/Promise/any/iter-arg-is-empty-iterable-reject.js
+    expect(
+      await value(`
+        try {
+          await Promise.any([])
+          return "fulfilled"
+        } catch (error) {
+          return [error instanceof AggregateError, error.errors.length]
+        }
+      `),
+    ).toEqual([true, 0])
+  })
+
+  test("consumes a string input as its characters", async () => {
+    // Source: test/built-ins/Promise/any/iter-arg-is-string-resolve.js
+    expect(await value(`return await Promise.any("abc")`)).toBe("a")
+  })
+
+  test("rejects an empty string input with an empty AggregateError", async () => {
+    // Source: test/built-ins/Promise/any/iter-arg-is-empty-string-reject.js
+    expect(
+      await value(`
+        try {
+          await Promise.any("")
+          return "fulfilled"
+        } catch (error) {
+          return [error instanceof AggregateError, error.errors.length]
+        }
+      `),
+    ).toEqual([true, 0])
+  })
+
+  test("fulfills with the first member that does not reject", async () => {
+    // Sources:
+    // test/built-ins/Promise/any/resolve-from-reject-catch.js
+    // test/built-ins/Promise/any/resolve-from-resolve-reject-catch.js
+    expect(
+      await value(`
+        return await Promise.any([
+          Promise.reject("a"),
+          new Promise((resolve, reject) => reject("b")),
+          Promise.all([Promise.reject("c")]),
+          Promise.resolve(Promise.reject("d").catch((reason) => reason)),
+        ])
+      `),
+    ).toBe("d")
+  })
+
+  test("settles after reactions attached to its inputs", async () => {
+    // Source: test/built-ins/Promise/any/resolved-sequence.js
+    expect(
+      await value(`
+        const sequence = [1]
+        const input = Promise.resolve(1)
+        const aggregate = Promise.any([input])
+        aggregate.then(() => sequence.push(4))
+        input.then(() => sequence.push(3)).then(() => sequence.push(5))
+        sequence.push(2)
+        await aggregate
+        await Promise.resolve()
+        return sequence
+      `),
+    ).toEqual([1, 2, 3, 4, 5])
+  })
+})
+
+describe("Test262 AggregateError", () => {
+  test("constructs from an errors collection and an optional message", async () => {
+    // Sources:
+    // test/built-ins/AggregateError/errors-iterabletolist.js
+    // test/built-ins/AggregateError/message-undefined-no-prop.js
+    expect(
+      await value(`
+        const input = ["x", "y"]
+        const withMessage = new AggregateError(input, "msg")
+        const bare = new AggregateError([])
+        return [
+          withMessage.name,
+          withMessage.message,
+          withMessage.errors,
+          withMessage.errors !== input,
+          withMessage instanceof AggregateError,
+          withMessage instanceof Error,
+          bare.message,
+          bare.errors,
+        ]
+      `),
+    ).toEqual(["AggregateError", "msg", ["x", "y"], true, true, true, "", []])
+  })
+
+  test("rejects a non-collection errors argument with TypeError", async () => {
+    // Source: test/built-ins/AggregateError/errors-iterabletolist-failures.js
+    expect(
+      await value(`
+        try {
+          new AggregateError(42)
+          return "constructed"
+        } catch (error) {
+          return error.name
+        }
+      `),
+    ).toBe("TypeError")
+  })
+
+  test("is callable without new", async () => {
+    // Source: test/built-ins/AggregateError/newtarget-is-undefined.js
+    expect(
+      await value(`
+        const error = AggregateError(["x"], "m")
+        return [error instanceof AggregateError, error instanceof Error, error.name, error.message, error.errors]
+      `),
+    ).toEqual([true, true, "AggregateError", "m", ["x"]])
+  })
+
+  test("coerces a non-string message to a string", async () => {
+    // Source: test/built-ins/AggregateError/message-method-prop-cast.js (value coercion only; the
+    // upstream object-with-toString case is omitted because the sandbox has no user toString dispatch)
+    expect(
+      await value(`
+        return [
+          new AggregateError([], 42).message,
+          new AggregateError([], false).message,
+          new AggregateError([], true).message,
+          new AggregateError([], null).message,
+        ]
+      `),
+    ).toEqual(["42", "false", "true", "null"])
+  })
+})
+
+describe("Test262 Promise constructor", () => {
+  test("constructs a promise, handing the executor callable resolve/reject", async () => {
+    // Sources:
+    // test/built-ins/Promise/constructor.js
+    // test/built-ins/Promise/exec-args.js
+    expect(
+      await value(`
+        let observed
+        const promise = new Promise((resolve, reject) => {
+          observed = [typeof resolve, typeof reject]
+          resolve("done")
+        })
+        return [promise instanceof Promise, observed, await promise]
+      `),
+    ).toEqual([true, ["function", "function"], "done"])
+  })
+
+  test("a missing or non-callable executor is a TypeError", async () => {
+    // Source: test/built-ins/Promise/executor-not-callable.js
+    expect(
+      await value(`
+        const outcomes = []
+        for (const make of [() => new Promise(), () => new Promise(1), () => new Promise({})]) {
+          try {
+            make()
+            outcomes.push("constructed")
+          } catch (error) {
+            outcomes.push(error.name)
+          }
+        }
+        return outcomes
+      `),
+    ).toEqual(["TypeError", "TypeError", "TypeError"])
+  })
+
+  test("resolves immediately or later through an escaping resolver", async () => {
+    // Sources:
+    // test/built-ins/Promise/resolve-non-thenable-immed.js
+    // test/built-ins/Promise/resolve-non-thenable-deferred.js
+    // test/built-ins/Promise/create-resolving-functions-resolve.js
+    expect(
+      await value(`
+        let settle
+        const deferred = new Promise((resolve) => { settle = resolve })
+        const immediate = new Promise((resolve) => resolve("now"))
+        settle("later")
+        return [await immediate, await deferred]
+      `),
+    ).toEqual(["now", "later"])
+  })
+
+  test("rejects through reject and through an abrupt executor completion", async () => {
+    // Sources:
+    // test/built-ins/Promise/reject-via-fn-immed.js
+    // test/built-ins/Promise/reject-via-abrupt.js
+    expect(
+      await value(`
+        const observe = async (promise) => {
+          try { return ["fulfilled", await promise] } catch (reason) { return ["rejected", reason.message ?? reason] }
+        }
+        return [
+          await observe(new Promise((_, reject) => reject("nope"))),
+          await observe(new Promise(() => { throw new Error("boom") })),
+        ]
+      `),
+    ).toEqual([
+      ["rejected", "nope"],
+      ["rejected", "boom"],
+    ])
+  })
+
+  test("only the first settlement counts", async () => {
+    // Sources:
+    // test/built-ins/Promise/reject-ignored-via-fn-immed.js
+    // test/built-ins/Promise/resolve-ignored-via-fn-immed.js
+    expect(
+      await value(`
+        return [
+          await new Promise((resolve, reject) => { resolve("first"); reject("second"); resolve("third") }),
+          await new Promise((resolve) => { resolve(resolve("inner") === undefined ? "unreached" : "also unreached") }),
+        ]
+      `),
+    ).toEqual(["first", "inner"])
+  })
+
+  test("escaped resolvers keep first-settle-wins in both directions", async () => {
+    // Sources:
+    // test/built-ins/Promise/reject-ignored-via-fn-deferred.js
+    // test/built-ins/Promise/resolve-ignored-via-fn-deferred.js
+    expect(
+      await value(`
+        let resolveRejected, rejectRejected
+        const rejected = new Promise((resolve, reject) => { resolveRejected = resolve; rejectRejected = reject })
+        rejectRejected("first")
+        const lateResolve = resolveRejected("late")
+        let resolveFulfilled, rejectFulfilled
+        const fulfilled = new Promise((resolve, reject) => { resolveFulfilled = resolve; rejectFulfilled = reject })
+        resolveFulfilled()
+        const lateReject = rejectFulfilled(new Promise(() => {}))
+        try {
+          await rejected
+          return "fulfilled"
+        } catch (reason) {
+          return [reason, lateResolve === undefined, (await fulfilled) === undefined, lateReject === undefined]
+        }
+      `),
+    ).toEqual(["first", true, true, true])
+  })
+
+  test("a queued reaction chain observes a later rejection through a handler-less then", async () => {
+    // Sources:
+    // test/built-ins/Promise/reject-via-fn-immed-queue.js
+    // test/built-ins/Promise/reject-via-fn-deferred-queue.js
+    // test/built-ins/Promise/reject-via-abrupt-queue.js
+    expect(
+      await value(`
+        const observe = (promise) => promise.then(() => "wrong").then(() => "also wrong", (reason) => "caught:" + reason)
+        let reject
+        const deferred = new Promise((_, r) => { reject = r })
+        const chained = observe(deferred)
+        reject("boom")
+        return [
+          await observe(new Promise((_, r) => r("immed"))),
+          await chained,
+          await observe(new Promise(() => { throw "abrupt" })),
+        ]
+      `),
+    ).toEqual(["caught:immed", "caught:boom", "caught:abrupt"])
+  })
+
+  test("an exception after resolve is ignored", async () => {
+    // Source: test/built-ins/Promise/exception-after-resolve-in-executor.js
+    expect(await value(`return await new Promise((resolve) => { resolve("kept"); throw new Error("dropped") })`)).toBe(
+      "kept",
+    )
+  })
+
+  test("resolving with a promise adopts its settlement", async () => {
+    // Sources:
+    // test/built-ins/Promise/resolve-thenable-immed.js (promise-adoption portion)
+    // test/built-ins/Promise/all/S25.4.4.1_A2.3_T1.js (resolution adoption semantics)
+    expect(
+      await value(`
+        const adoptedValue = await new Promise((resolve) => resolve(Promise.resolve("adopted")))
+        try {
+          await new Promise((resolve) => resolve(Promise.reject("bad")))
+          return [adoptedValue, "fulfilled"]
+        } catch (reason) {
+          return [adoptedValue, reason]
+        }
+      `),
+    ).toEqual(["adopted", "bad"])
+  })
+
+  test("resolving with the promise itself rejects with TypeError", async () => {
+    // Source: test/built-ins/Promise/resolve-self.js
+    expect(
+      await value(`
+        let settle
+        const promise = new Promise((resolve) => { settle = resolve })
+        settle(promise)
+        try {
+          await promise
+          return "fulfilled"
+        } catch (error) {
+          return error.name
+        }
+      `),
+    ).toBe("TypeError")
+  })
+
+  test("executor runs synchronously before the constructor returns", async () => {
+    // Source: test/built-ins/Promise/executor-call-context-strict.js (synchronous Call(executor) step)
+    expect(
+      await value(`
+        const sequence = []
+        sequence.push("before")
+        new Promise((resolve) => { sequence.push("executor"); resolve() })
+        sequence.push("after")
+        return sequence
+      `),
+    ).toEqual(["before", "executor", "after"])
+  })
+
+  test.failing("calling Promise without new throws TypeError", async () => {
+    // Source: test/built-ins/Promise/undefined-newtarget.js
+    // The sandbox currently reports a generic Error ("Only tools are callable in CodeMode.").
+    expect(
+      await value(`
+        try {
+          Promise(() => {})
+          return "called"
+        } catch (error) {
+          return error.name
+        }
+      `),
+    ).toBe("TypeError")
+  })
+})

packages/codemode/test/promise.test.ts

@@ -3,8 +3,9 @@ import { Effect, Schema } from "effect"
 import { CodeMode, Tool, toolError } from "../src/index.js"
 
 // Wave 5 acceptance suite: first-class promise values. Un-awaited tool calls start eagerly on
-// supervised fibers, `await` settles them, and Promise.all/allSettled/race/resolve/reject are
-// ordinary functions over arbitrary arrays mixing promises and plain values.
+// supervised fibers, `await` settles them, Promise.all/allSettled/race/resolve/reject are
+// ordinary functions over arbitrary arrays mixing promises and plain values, and
+// .then/.catch/.finally chain reactions onto any promise.
 
 type Trace = {
   starts: Array<number>
@@ -184,7 +185,7 @@ describe("first-class promise values", () => {
     expect(result.toolCalls).toStrictEqual([{ name: "host.sleepy" }])
   })
 
-  test("await of a non-promise value is a passthrough no-op", async () => {
+  test("await of a non-promise value passes it through unchanged", async () => {
     expect(await value(`return await 42`)).toBe(42)
     expect(await value(`const x = await "s"; return x`)).toBe("s")
     expect(await value(`return await null`)).toBeNull()
@@ -935,16 +936,124 @@ describe("timeout interruption of forked calls", () => {
   })
 })
 
-describe("unsupported promise surface", () => {
-  test(".then/.catch/.finally give a clear await-instead error", async () => {
-    for (const method of ["then", "catch", "finally"]) {
-      const diagnostic = await error(`return tools.host.sleepy({ id: 1 }).${method}((x) => x)`)
-      expect(diagnostic.kind).toBe("UnsupportedSyntax")
-      expect(diagnostic.message).toContain(`Promise.prototype.${method} is not supported`)
-      expect(diagnostic.message).toContain("await")
-    }
+describe("promise chaining", () => {
+  test("then transforms tool results and adopts returned promises across a chain", async () => {
+    expect(
+      await value(`
+        return await tools.host
+          .sleepy({ id: 2 })
+          .then((id) => tools.host.sleepy({ id: id + 1 }))
+          .then((id) => id * 10)
+      `),
+    ).toBe(30)
   })
 
+  test("handlers are deferred and run in attach order", async () => {
+    expect(
+      await value(`
+        const order = []
+        const promise = Promise.resolve(1)
+        promise.then(() => order.push("h1"))
+        promise.then(() => order.push("h2"))
+        order.push("sync")
+        await promise
+        return order
+      `),
+    ).toEqual(["sync", "h1", "h2"])
+  })
+
+  test("catch recovers a tool failure and preserves fulfillment", async () => {
+    expect(
+      await value(`
+        return [
+          await tools.host.fail({}).catch((error) => error.message),
+          await tools.host.sleepy({ id: 4 }).catch(() => "unused"),
+        ]
+      `),
+    ).toEqual(["Lookup refused", 4])
+  })
+
+  test("finally observes settlement without changing the value", async () => {
+    expect(
+      await value(`
+        const events = []
+        const result = await tools.host.sleepy({ id: 5 }).finally(() => events.push("cleanup"))
+        return [result, events]
+      `),
+    ).toEqual([5, ["cleanup"]])
+  })
+
+  test("a settled, un-awaited rejected chain tail warns exactly once", async () => {
+    const result = await run(`
+      Promise.reject(new Error("boom")).then((value) => value)
+      await Promise.resolve()
+      return "done"
+    `)
+    expect(result.ok).toBe(true)
+    if (!result.ok) return
+    expect(result.value).toBe("done")
+    // The source rejection belongs to the chain (no warning); only the derived tail warns.
+    expect(result.warnings).toStrictEqual([
+      { kind: "ExecutionFailure", message: "Unhandled rejection from an un-awaited promise: Uncaught: boom" },
+    ])
+  })
+
+  test("a catch handler silences the chain's rejection warning", async () => {
+    const result = await run(`
+      Promise.reject(new Error("boom")).catch(() => "handled")
+      await Promise.resolve()
+      return "done"
+    `)
+    expect(result.ok).toBe(true)
+    if (!result.ok) return
+    expect(result.warnings).toBeUndefined()
+  })
+
+  test("non-plain-function handlers fail loudly instead of being ignored", async () => {
+    const diagnostic = await error(`return await tools.host.sleepy({ id: 1 }).then(tools.host.completed)`)
+    expect(diagnostic.message).toContain("Promise.prototype.then handlers must be plain functions")
+  })
+
+  test("chaining methods are opaque references until called", async () => {
+    expect(await value(`return typeof tools.host.sleepy({ id: 1 }).then`)).toBe("function")
+  })
+})
+
+describe("combinator settlement timing", () => {
+  test("a combinator settling one reaction turn after the program returns is interrupted silently", async () => {
+    // The aggregate's one-turn settlement delay (V8 parity) means an immediately-returning
+    // program abandons it while still pending: interrupted like any pending work, so no
+    // rejection warning survives - the member itself was observed by the combinator.
+    const result = await run(`
+      Promise.all([Promise.reject(new Error("boom"))])
+      return "done"
+    `)
+    expect(result.ok).toBe(true)
+    if (!result.ok) return
+    expect(result.value).toBe("done")
+    expect(result.warnings).toBeUndefined()
+  })
+
+  test("a combinator settles one reaction turn after its members, as in V8", async () => {
+    // Regression for the race winner flip: Promise.all's settlement burns a reaction turn,
+    // so a plain resolved value entered in the same race wins, and a fail-fast aggregate
+    // cannot beat it into rejection.
+    expect(
+      await value(`
+        const pending = tools.host.sleepy({ id: 9, ms: 60000 })
+        const winner = await Promise.race([Promise.all([Promise.resolve(1)]), Promise.resolve(2)])
+        try {
+          const raced = await Promise.race([Promise.all([Promise.reject("x"), pending]), Promise.resolve("ok")])
+          return [winner, "fulfilled", raced]
+        } catch (reason) {
+          return [winner, "rejected", reason]
+        }
+      `),
+    ).toEqual([2, "fulfilled", "ok"])
+  })
+})
+
+describe("unsupported promise surface", () => {
   test("other property reads on a promise hint at the missing await", async () => {
     const diagnostic = await error(`return tools.host.sleepy({ id: 1 }).value`)
     expect(diagnostic.kind).toBe("InvalidDataValue")
@@ -953,15 +1062,179 @@ describe("unsupported promise surface", () => {
   })
 
   test("unknown Promise statics list what is available", async () => {
-    const diagnostic = await error(`return await Promise.any([tools.host.sleepy({ id: 1 })])`)
-    expect(diagnostic.message).toContain("Promise.any is not available")
-    expect(diagnostic.message).toContain("Promise.allSettled")
-  })
-
-  test("new Promise(...) points at tool calls instead", async () => {
-    const diagnostic = await error(`return new Promise((resolve) => resolve(1))`)
-    expect(diagnostic.kind).toBe("UnsupportedSyntax")
-    expect(diagnostic.message).toContain("new Promise(...) is not supported")
-    expect(diagnostic.message).toContain("already return promises")
+    const diagnostic = await error(`return await Promise.withResolvers()`)
+    expect(diagnostic.message).toContain("Promise.withResolvers is not available")
+    expect(diagnostic.message).toContain("Promise.any")
+  })
+})
+
+describe("Promise.any", () => {
+  test("first tool success wins; failing and losing calls are handled silently", async () => {
+    const trace = makeTrace()
+    const result = await run(
+      `
+        const winner = await Promise.any([
+          tools.host.fail({}),
+          tools.host.sleepy({ id: 1, ms: 5 }),
+          tools.host.sleepy({ id: 2, ms: 60000 }),
+        ])
+        return winner
+      `,
+      { trace },
+    )
+    expect(result.ok).toBe(true)
+    if (!result.ok) return
+    expect(result.value).toBe(1)
+    // The slow loser stays execution-owned and is interrupted at completion; the tool
+    // failure was observed by the aggregate, so no rejection warning survives.
+    expect(result.warnings).toBeUndefined()
+    expect(trace.interrupted).toBe(1)
+  })
+
+  test("all members failing rejects with catch-normalized reasons in input order", async () => {
+    expect(
+      await value(`
+        try {
+          await Promise.any([tools.host.fail({}), Promise.reject("plain")])
+          return "fulfilled"
+        } catch (error) {
+          return [error.name, error.errors.map((reason) => reason.message ?? reason)]
+        }
+      `),
+    ).toEqual(["AggregateError", ["Lookup refused", "plain"]])
+  })
+
+  test("settles one reaction turn after its deciding member, as in V8", async () => {
+    expect(await value(`return await Promise.race([Promise.any([Promise.resolve(1)]), Promise.resolve(2)])`)).toBe(2)
+  })
+
+  test("a tie is decided by settlement order, not input order", async () => {
+    // Handlers run in attach order, so `first` settles before `second` and wins
+    // despite its later input position - as in real JS.
+    expect(
+      await value(`
+        const first = Promise.resolve().then(() => "one")
+        const second = Promise.resolve().then(() => "two")
+        return await Promise.any([second, first])
+      `),
+    ).toBe("one")
+  })
+
+  test("an abandoned rejecting aggregate is interrupted silently at the return", async () => {
+    const result = await run(`
+      Promise.any([Promise.reject(new Error("boom"))])
+      return "done"
+    `)
+    expect(result.ok).toBe(true)
+    if (!result.ok) return
+    expect(result.value).toBe("done")
+    expect(result.warnings).toBeUndefined()
+  })
+})
+
+describe("promise construction", () => {
+  test("a deferred gate coordinates tool results across async functions", async () => {
+    expect(
+      await value(`
+        let openGate
+        const gate = new Promise((resolve) => { openGate = resolve })
+        const worker = (async () => {
+          const id = await gate
+          return id * 2
+        })()
+        openGate(await tools.host.sleepy({ id: 21, ms: 5 }))
+        return await worker
+      `),
+    ).toBe(42)
+  })
+
+  test("the .then(resolve) bridge settles a constructed promise", async () => {
+    expect(
+      await value(`
+        const bridged = new Promise((resolve, reject) => {
+          tools.host.sleepy({ id: 7, ms: 5 }).then(resolve, reject)
+        })
+        return await bridged
+      `),
+    ).toBe(7)
+  })
+
+  test("constructed promises participate in combinators", async () => {
+    expect(
+      await value(`
+        let settle
+        const manual = new Promise((resolve) => { settle = resolve })
+        const race = Promise.race([manual, tools.host.sleepy({ id: 3, ms: 60000 })])
+        const all = Promise.all([manual, "plain"])
+        const any = Promise.any([manual, new Promise(() => {})])
+        settle("manual")
+        return [await race, await all, await any]
+      `),
+    ).toEqual(["manual", ["manual", "plain"], "manual"])
+  })
+
+  test("resolving with a pending promise adopts its later settlement", async () => {
+    expect(
+      await value(`
+        let innerResolve, innerReject
+        const adopted = new Promise((resolve) => resolve(new Promise((resolve) => { innerResolve = resolve })))
+        const adoptedRejection = new Promise((resolve) => resolve(new Promise((_, reject) => { innerReject = reject })))
+        innerResolve("later")
+        innerReject("bad")
+        try {
+          return [await adopted, await adoptedRejection]
+        } catch (reason) {
+          return [await adopted, reason]
+        }
+      `),
+    ).toEqual(["later", "bad"])
+  })
+
+  test("an async executor's post-await resolve settles the promise", async () => {
+    expect(
+      await value(`
+        const result = new Promise(async (resolve) => {
+          const id = await tools.host.sleepy({ id: 5, ms: 5 })
+          resolve(id * 2)
+        })
+        return await result
+      `),
+    ).toBe(10)
+  })
+
+  test("a never-settled promise is abandoned silently at the return", async () => {
+    const result = await run(`
+      const forever = new Promise(() => {})
+      forever.then(() => {})
+      return "done"
+    `)
+    expect(result.ok).toBe(true)
+    if (!result.ok) return
+    expect(result.value).toBe("done")
+    expect(result.warnings).toBeUndefined()
+  })
+
+  test("an un-awaited constructed rejection is reported like any unhandled rejection", async () => {
+    const result = await run(`
+      new Promise((_, reject) => reject(new Error("dropped")))
+      await Promise.resolve()
+      await Promise.resolve()
+      return "done"
+    `)
+    expect(result.ok).toBe(true)
+    if (!result.ok) return
+    expect(result.value).toBe("done")
+    expect(result.warnings).toHaveLength(1)
+    expect(result.warnings?.[0].message).toContain("Unhandled rejection")
+    expect(result.warnings?.[0].message).toContain("dropped")
+  })
+
+  test("resolver functions cannot cross the data boundary", async () => {
+    const diagnostic = await error(`
+      let escaped
+      new Promise((resolve) => { escaped = resolve })
+      return { escaped }
+    `)
+    expect(diagnostic.kind).toBe("InvalidDataValue")
   })
 })

packages/codemode/test/signature.test.ts

@@ -342,9 +342,7 @@ describe("JSDoc signatures in catalogs and search results", () => {
   const runtime = CodeMode.make({ tools: { github: { list_issues: listIssues }, orders: { lookup: lookupOrder } } })
 
   const search = async (query: string) => {
-    const result = await Effect.runPromise(
-      runtime.execute(`return await tools.$codemode.search({ query: ${JSON.stringify(query)} })`),
-    )
+    const result = await Effect.runPromise(runtime.execute(`return search({ query: ${JSON.stringify(query)} })`))
     expect(result.ok).toBe(true)
     if (!result.ok) throw new Error("search failed")
     return result.value as { items: Array<{ path: string; signature: string }>; remaining: number }
@@ -436,9 +434,7 @@ describe("non-identifier tool paths", () => {
   })
 
   test("search results return callable bracket-notation paths and signatures", async () => {
-    const result = await Effect.runPromise(
-      runtime.execute(`return await tools.$codemode.search({ query: "resolve library" })`),
-    )
+    const result = await Effect.runPromise(runtime.execute(`return search({ query: "resolve library" })`))
     expect(result.ok).toBe(true)
     if (!result.ok) throw new Error("search failed")
 

packages/console/app/public/robots.txt

@@ -3,4 +3,7 @@ Allow: /
 
 # Disallow shared content pages
 Disallow: /s/
-Disallow: /share/
+Disallow: /share/
+
+Sitemap: https://opencode.ai/sitemap.xml
+Sitemap: https://opencode.ai/data/sitemap.xml

packages/console/app/src/routes/zen/util/provider/openai.ts

@@ -4,6 +4,7 @@ type Usage = {
   input_tokens?: number
   input_tokens_details?: {
     cached_tokens?: number
+    cache_write_tokens?: number
   }
   output_tokens?: number
   output_tokens_details?: {
@@ -48,12 +49,13 @@ export const openaiHelper: ProviderHelper = ({ workspaceID }) => ({
     const outputTokens = usage.output_tokens ?? 0
     const reasoningTokens = usage.output_tokens_details?.reasoning_tokens ?? undefined
     const cacheReadTokens = usage.input_tokens_details?.cached_tokens ?? undefined
+    const cacheWriteTokens = usage.input_tokens_details?.cache_write_tokens ?? undefined
     return {
       inputTokens: inputTokens - (cacheReadTokens ?? 0),
       outputTokens,
       reasoningTokens,
       cacheReadTokens,
-      cacheWrite5mTokens: undefined,
+      cacheWrite5mTokens: cacheWriteTokens,
       cacheWrite1hTokens: undefined,
     }
   },

packages/console/app/test/providerUsage.test.ts

@@ -65,4 +65,20 @@ describe("provider usage extraction", () => {
       output_tokens: 7,
     })
   })
+
+  test("parses OpenAI stream cache write usage", () => {
+    const usageParser = providers.openai.createUsageParser()
+    usageParser.parse(
+      'event: response.completed\ndata: {"response":{"usage":{"input_tokens":10,"input_tokens_details":{"cached_tokens":4,"cache_write_tokens":3},"output_tokens":2}}}',
+    )
+
+    expect(providers.openai.normalizeUsage(usageParser.retrieve())).toEqual({
+      inputTokens: 6,
+      outputTokens: 2,
+      reasoningTokens: undefined,
+      cacheReadTokens: 4,
+      cacheWrite5mTokens: 3,
+      cacheWrite1hTokens: undefined,
+    })
+  })
 })

packages/core/schema.json

@@ -1,8 +1,10 @@
 {
   "version": "7",
   "dialect": "sqlite",
-  "id": "2c759c08-79c8-4179-9e15-d2fea45c9dec",
-  "prevIds": ["01451b27-1e51-4657-b2d0-4b457dffa3ec"],
+  "id": "5f0a1db8-d4bf-42c3-becb-96b46fe66bed",
+  "prevIds": [
+    "666138ef-82cb-4a9a-a765-e6669a436ff3"
+  ],
   "ddl": [
     {
       "name": "workspace",
@@ -49,13 +51,17 @@
       "entityType": "tables"
     },
     {
-      "name": "instruction_checkpoint",
+      "name": "instruction_blob",
       "entityType": "tables"
     },
     {
       "name": "instruction_entry",
       "entityType": "tables"
     },
+    {
+      "name": "instruction_state",
+      "entityType": "tables"
+    },
     {
       "name": "message",
       "entityType": "tables"
@@ -786,39 +792,19 @@
       "autoincrement": false,
       "default": null,
       "generated": null,
-      "name": "session_id",
+      "name": "hash",
       "entityType": "columns",
-      "table": "instruction_checkpoint"
+      "table": "instruction_blob"
     },
     {
       "type": "text",
-      "notNull": true,
+      "notNull": false,
       "autoincrement": false,
       "default": null,
       "generated": null,
-      "name": "baseline",
+      "name": "value",
       "entityType": "columns",
-      "table": "instruction_checkpoint"
-    },
-    {
-      "type": "text",
-      "notNull": true,
-      "autoincrement": false,
-      "default": null,
-      "generated": null,
-      "name": "snapshot",
-      "entityType": "columns",
-      "table": "instruction_checkpoint"
-    },
-    {
-      "type": "integer",
-      "notNull": true,
-      "autoincrement": false,
-      "default": null,
-      "generated": null,
-      "name": "baseline_seq",
-      "entityType": "columns",
-      "table": "instruction_checkpoint"
+      "table": "instruction_blob"
     },
     {
       "type": "text",
@@ -842,7 +828,7 @@
     },
     {
       "type": "text",
-      "notNull": true,
+      "notNull": false,
       "autoincrement": false,
       "default": null,
       "generated": null,
@@ -850,6 +836,16 @@
       "entityType": "columns",
       "table": "instruction_entry"
     },
+    {
+      "type": "integer",
+      "notNull": true,
+      "autoincrement": false,
+      "default": "false",
+      "generated": null,
+      "name": "removed",
+      "entityType": "columns",
+      "table": "instruction_entry"
+    },
     {
       "type": "integer",
       "notNull": true,
@@ -870,6 +866,56 @@
       "entityType": "columns",
       "table": "instruction_entry"
     },
+    {
+      "type": "text",
+      "notNull": false,
+      "autoincrement": false,
+      "default": null,
+      "generated": null,
+      "name": "session_id",
+      "entityType": "columns",
+      "table": "instruction_state"
+    },
+    {
+      "type": "integer",
+      "notNull": true,
+      "autoincrement": false,
+      "default": null,
+      "generated": null,
+      "name": "epoch_start",
+      "entityType": "columns",
+      "table": "instruction_state"
+    },
+    {
+      "type": "integer",
+      "notNull": true,
+      "autoincrement": false,
+      "default": null,
+      "generated": null,
+      "name": "through_seq",
+      "entityType": "columns",
+      "table": "instruction_state"
+    },
+    {
+      "type": "text",
+      "notNull": true,
+      "autoincrement": false,
+      "default": null,
+      "generated": null,
+      "name": "initial_values",
+      "entityType": "columns",
+      "table": "instruction_state"
+    },
+    {
+      "type": "text",
+      "notNull": true,
+      "autoincrement": false,
+      "default": null,
+      "generated": null,
+      "name": "current_values",
+      "entityType": "columns",
+      "table": "instruction_state"
+    },
     {
       "type": "text",
       "notNull": false,
@@ -1180,6 +1226,16 @@
       "entityType": "columns",
       "table": "session"
     },
+    {
+      "type": "integer",
+      "notNull": false,
+      "autoincrement": false,
+      "default": null,
+      "generated": null,
+      "name": "fork_seq",
+      "entityType": "columns",
+      "table": "session"
+    },
     {
       "type": "text",
       "notNull": true,
@@ -1501,9 +1557,13 @@
       "table": "session_share"
     },
     {
-      "columns": ["project_id"],
+      "columns": [
+        "project_id"
+      ],
       "tableTo": "project",
-      "columnsTo": ["id"],
+      "columnsTo": [
+        "id"
+      ],
       "onUpdate": "NO ACTION",
       "onDelete": "CASCADE",
       "nameExplicit": false,
@@ -1512,9 +1572,13 @@
       "table": "workspace"
     },
     {
-      "columns": ["active_account_id"],
+      "columns": [
+        "active_account_id"
+      ],
       "tableTo": "account",
-      "columnsTo": ["id"],
+      "columnsTo": [
+        "id"
+      ],
       "onUpdate": "NO ACTION",
       "onDelete": "SET NULL",
       "nameExplicit": false,
@@ -1523,9 +1587,13 @@
       "table": "account_state"
     },
     {
-      "columns": ["aggregate_id"],
+      "columns": [
+        "aggregate_id"
+      ],
       "tableTo": "event_sequence",
-      "columnsTo": ["aggregate_id"],
+      "columnsTo": [
+        "aggregate_id"
+      ],
       "onUpdate": "NO ACTION",
       "onDelete": "CASCADE",
       "nameExplicit": false,
@@ -1534,9 +1602,13 @@
       "table": "event"
     },
     {
-      "columns": ["project_id"],
+      "columns": [
+        "project_id"
+      ],
       "tableTo": "project",
-      "columnsTo": ["id"],
+      "columnsTo": [
+        "id"
+      ],
       "onUpdate": "NO ACTION",
       "onDelete": "CASCADE",
       "nameExplicit": false,
@@ -1545,9 +1617,13 @@
       "table": "permission"
     },
     {
-      "columns": ["project_id"],
+      "columns": [
+        "project_id"
+      ],
       "tableTo": "project",
-      "columnsTo": ["id"],
+      "columnsTo": [
+        "id"
+      ],
       "onUpdate": "NO ACTION",
       "onDelete": "CASCADE",
       "nameExplicit": false,
@@ -1556,20 +1632,13 @@
       "table": "project_directory"
     },
     {
-      "columns": ["session_id"],
+      "columns": [
+        "session_id"
+      ],
       "tableTo": "session",
-      "columnsTo": ["id"],
-      "onUpdate": "NO ACTION",
-      "onDelete": "CASCADE",
-      "nameExplicit": false,
-      "name": "fk_instruction_checkpoint_session_id_session_id_fk",
-      "entityType": "fks",
-      "table": "instruction_checkpoint"
-    },
-    {
-      "columns": ["session_id"],
-      "tableTo": "session",
-      "columnsTo": ["id"],
+      "columnsTo": [
+        "id"
+      ],
       "onUpdate": "NO ACTION",
       "onDelete": "CASCADE",
       "nameExplicit": false,
@@ -1578,9 +1647,28 @@
       "table": "instruction_entry"
     },
     {
-      "columns": ["session_id"],
+      "columns": [
+        "session_id"
+      ],
       "tableTo": "session",
-      "columnsTo": ["id"],
+      "columnsTo": [
+        "id"
+      ],
+      "onUpdate": "NO ACTION",
+      "onDelete": "CASCADE",
+      "nameExplicit": false,
+      "name": "fk_instruction_state_session_id_session_id_fk",
+      "entityType": "fks",
+      "table": "instruction_state"
+    },
+    {
+      "columns": [
+        "session_id"
+      ],
+      "tableTo": "session",
+      "columnsTo": [
+        "id"
+      ],
       "onUpdate": "NO ACTION",
       "onDelete": "CASCADE",
       "nameExplicit": false,
@@ -1589,9 +1677,13 @@
       "table": "message"
     },
     {
-      "columns": ["message_id"],
+      "columns": [
+        "message_id"
+      ],
       "tableTo": "message",
-      "columnsTo": ["id"],
+      "columnsTo": [
+        "id"
+      ],
       "onUpdate": "NO ACTION",
       "onDelete": "CASCADE",
       "nameExplicit": false,
@@ -1600,9 +1692,13 @@
       "table": "part"
     },
     {
-      "columns": ["session_id"],
+      "columns": [
+        "session_id"
+      ],
       "tableTo": "session",
-      "columnsTo": ["id"],
+      "columnsTo": [
+        "id"
+      ],
       "onUpdate": "NO ACTION",
       "onDelete": "CASCADE",
       "nameExplicit": false,
@@ -1611,9 +1707,13 @@
       "table": "session_message"
     },
     {
-      "columns": ["session_id"],
+      "columns": [
+        "session_id"
+      ],
       "tableTo": "session",
-      "columnsTo": ["id"],
+      "columnsTo": [
+        "id"
+      ],
       "onUpdate": "NO ACTION",
       "onDelete": "CASCADE",
       "nameExplicit": false,
@@ -1622,9 +1722,13 @@
       "table": "session_pending"
     },
     {
-      "columns": ["project_id"],
+      "columns": [
+        "project_id"
+      ],
       "tableTo": "project",
-      "columnsTo": ["id"],
+      "columnsTo": [
+        "id"
+      ],
       "onUpdate": "NO ACTION",
       "onDelete": "CASCADE",
       "nameExplicit": false,
@@ -1633,9 +1737,13 @@
       "table": "session"
     },
     {
-      "columns": ["session_id"],
+      "columns": [
+        "session_id"
+      ],
       "tableTo": "session",
-      "columnsTo": ["id"],
+      "columnsTo": [
+        "id"
+      ],
       "onUpdate": "NO ACTION",
       "onDelete": "CASCADE",
       "nameExplicit": false,
@@ -1644,133 +1752,183 @@
       "table": "session_share"
     },
     {
-      "columns": ["email", "url"],
+      "columns": [
+        "email",
+        "url"
+      ],
       "nameExplicit": false,
       "name": "control_account_pk",
       "entityType": "pks",
       "table": "control_account"
     },
     {
-      "columns": ["project_id", "directory"],
+      "columns": [
+        "project_id",
+        "directory"
+      ],
       "nameExplicit": false,
       "name": "project_directory_pk",
       "entityType": "pks",
       "table": "project_directory"
     },
     {
-      "columns": ["session_id", "key"],
+      "columns": [
+        "session_id",
+        "key"
+      ],
       "nameExplicit": false,
       "name": "instruction_entry_pk",
       "entityType": "pks",
       "table": "instruction_entry"
     },
     {
-      "columns": ["id"],
+      "columns": [
+        "id"
+      ],
       "nameExplicit": false,
       "name": "workspace_pk",
       "table": "workspace",
       "entityType": "pks"
     },
     {
-      "columns": ["name"],
+      "columns": [
+        "name"
+      ],
       "nameExplicit": false,
       "name": "data_migration_pk",
       "table": "data_migration",
       "entityType": "pks"
     },
     {
-      "columns": ["id"],
+      "columns": [
+        "id"
+      ],
       "nameExplicit": false,
       "name": "account_state_pk",
       "table": "account_state",
       "entityType": "pks"
     },
     {
-      "columns": ["id"],
+      "columns": [
+        "id"
+      ],
       "nameExplicit": false,
       "name": "account_pk",
       "table": "account",
       "entityType": "pks"
     },
     {
-      "columns": ["id"],
+      "columns": [
+        "id"
+      ],
       "nameExplicit": false,
       "name": "credential_pk",
       "table": "credential",
       "entityType": "pks"
     },
     {
-      "columns": ["aggregate_id"],
+      "columns": [
+        "aggregate_id"
+      ],
       "nameExplicit": false,
       "name": "event_sequence_pk",
       "table": "event_sequence",
       "entityType": "pks"
     },
     {
-      "columns": ["id"],
+      "columns": [
+        "id"
+      ],
       "nameExplicit": false,
       "name": "event_pk",
       "table": "event",
       "entityType": "pks"
     },
     {
-      "columns": ["id"],
+      "columns": [
+        "id"
+      ],
       "nameExplicit": false,
       "name": "permission_pk",
       "table": "permission",
       "entityType": "pks"
     },
     {
-      "columns": ["id"],
+      "columns": [
+        "id"
+      ],
       "nameExplicit": false,
       "name": "project_pk",
       "table": "project",
       "entityType": "pks"
     },
     {
-      "columns": ["session_id"],
+      "columns": [
+        "hash"
+      ],
       "nameExplicit": false,
-      "name": "instruction_checkpoint_pk",
-      "table": "instruction_checkpoint",
+      "name": "instruction_blob_pk",
+      "table": "instruction_blob",
       "entityType": "pks"
     },
     {
-      "columns": ["id"],
+      "columns": [
+        "session_id"
+      ],
+      "nameExplicit": false,
+      "name": "instruction_state_pk",
+      "table": "instruction_state",
+      "entityType": "pks"
+    },
+    {
+      "columns": [
+        "id"
+      ],
       "nameExplicit": false,
       "name": "message_pk",
       "table": "message",
       "entityType": "pks"
     },
     {
-      "columns": ["id"],
+      "columns": [
+        "id"
+      ],
       "nameExplicit": false,
       "name": "part_pk",
       "table": "part",
       "entityType": "pks"
     },
     {
-      "columns": ["id"],
+      "columns": [
+        "id"
+      ],
       "nameExplicit": false,
       "name": "session_message_pk",
       "table": "session_message",
       "entityType": "pks"
     },
     {
-      "columns": ["id"],
+      "columns": [
+        "id"
+      ],
       "nameExplicit": false,
       "name": "session_input_pk",
       "table": "session_pending",
       "entityType": "pks"
     },
     {
-      "columns": ["id"],
+      "columns": [
+        "id"
+      ],
       "nameExplicit": false,
       "name": "session_pk",
       "table": "session",
       "entityType": "pks"
     },
     {
-      "columns": ["session_id"],
+      "columns": [
+        "session_id"
+      ],
       "nameExplicit": false,
       "name": "session_share_pk",
       "table": "session_share",
@@ -2079,5 +2237,5 @@
       "table": "session"
     }
   ],
-  "renames": ["session_input->session_pending"]
-}
+  "renames": []
+}

packages/core/src/aisdk.ts

@@ -15,43 +15,20 @@ import type {
   SharedV3ProviderOptions,
 } from "@ai-sdk/provider"
 import {
-  APIError,
-  Authentication,
-  BadRequest,
-  ConnectionError,
   FinishReason,
-  HttpContext,
-  HttpRequestDetails,
-  HttpResponseDetails,
+  InvalidProviderOutputReason,
   LLMEvent,
-  MalformedResponse,
+  LLMError,
   Model,
-  NotFound,
   ProviderID,
   ProviderMetadata,
   ToolResultValue,
-  classifyApiFailure,
-  isLLMError,
-  type LLMError,
+  UnknownProviderReason,
   type ContentPart,
   type LLMRequest,
   type ToolDefinition,
   type UsageInput,
 } from "@opencode-ai/llm"
-import {
-  APICallError,
-  EmptyResponseBodyError,
-  InvalidArgumentError,
-  InvalidPromptError,
-  InvalidResponseDataError,
-  JSONParseError,
-  LoadAPIKeyError,
-  LoadSettingError,
-  NoContentGeneratedError,
-  NoSuchModelError,
-  TypeValidationError,
-  UnsupportedFunctionalityError,
-} from "@ai-sdk/provider"
 import { Auth, Endpoint, type AnyRoute } from "@opencode-ai/llm/route"
 import { Cause, Context, Effect, Layer, Option, Schema, Scope, Stream } from "effect"
 import { ModelV2 } from "./model"
@@ -513,12 +490,12 @@ function streamLanguage(language: LanguageModelV3, options: LanguageModelV3CallO
     Stream.unwrap(
       Effect.tryPromise({
         try: () => language.doStream(options),
-        catch: (error) => llmError(error),
+        catch: (error) => llmError("doStream", error),
       }).pipe(
         Effect.map((result) =>
           Stream.fromReadableStream({
             evaluate: () => result.stream,
-            onError: (error) => llmError(error),
+            onError: (error) => llmError("readStream", error),
           }).pipe(
             Stream.mapEffect((event) => streamPartEvents(state, event)),
             Stream.flatMap((events) => Stream.fromIterable(events)),
@@ -631,7 +608,7 @@ function streamPartEvents(
         }),
       ])
     case "error":
-      return Effect.fail(llmError(event.error))
+      return Effect.fail(llmError("stream", event.error))
   }
 }
 
@@ -689,65 +666,16 @@ function messageValue(input: unknown) {
   }
 }
 
-const BODY_LIMIT = 16_384
-
-const headerRetryAfterMs = (headers: Record<string, string> | undefined) => {
-  if (!headers) return undefined
-  const millis = Number(headers["retry-after-ms"])
-  if (Number.isFinite(millis)) return Math.max(0, millis)
-  const value = headers["retry-after"]
-  if (!value) return undefined
-  const seconds = Number(value)
-  if (Number.isFinite(seconds)) return Math.max(0, seconds * 1000)
-  const date = Date.parse(value)
-  if (!Number.isNaN(date)) return Math.max(0, date - Date.now())
-  return undefined
-}
-
-// Classify AI SDK failures into the shared `LLMError` union so the synthetic
-// AI SDK route reports failures identically to native protocol routes. An
-// `APICallError` without a status code is the AI SDK's representation of a
-// network-level failure (connect refused, reset, DNS), not an API rejection.
-function llmError(error: unknown): LLMError {
-  if (isLLMError(error)) return error
-  if (APICallError.isInstance(error)) {
-    if (error.statusCode === undefined) {
-      return new ConnectionError({ message: error.message, url: error.url, cause: error })
-    }
-    return classifyApiFailure({
-      message: error.message,
-      status: error.statusCode,
-      retryAfterMs: headerRetryAfterMs(error.responseHeaders),
-      requestID: error.responseHeaders?.["x-request-id"] ?? error.responseHeaders?.["request-id"],
-      http: new HttpContext({
-        request: new HttpRequestDetails({ method: "POST", url: error.url, headers: {} }),
-        response: new HttpResponseDetails({ status: error.statusCode, headers: error.responseHeaders ?? {} }),
-        body: error.responseBody === undefined ? undefined : error.responseBody.slice(0, BODY_LIMIT),
-        bodyTruncated: error.responseBody !== undefined && error.responseBody.length > BODY_LIMIT ? true : undefined,
-      }),
-    })
-  }
-  if (LoadAPIKeyError.isInstance(error) || LoadSettingError.isInstance(error)) {
-    return new Authentication({ message: error.message })
-  }
-  if (NoSuchModelError.isInstance(error)) return new NotFound({ message: error.message })
-  if (
-    InvalidPromptError.isInstance(error) ||
-    InvalidArgumentError.isInstance(error) ||
-    UnsupportedFunctionalityError.isInstance(error)
-  ) {
-    return new BadRequest({ message: error.message })
-  }
-  if (
-    InvalidResponseDataError.isInstance(error) ||
-    JSONParseError.isInstance(error) ||
-    TypeValidationError.isInstance(error) ||
-    EmptyResponseBodyError.isInstance(error) ||
-    NoContentGeneratedError.isInstance(error)
-  ) {
-    return new MalformedResponse({ message: error.message })
-  }
-  return new APIError({ message: error instanceof Error ? error.message : String(error) })
+function llmError(method: string, error: unknown) {
+  const reason =
+    error instanceof LLMError
+      ? new InvalidProviderOutputReason({ message: error.message })
+      : new UnknownProviderReason({ message: error instanceof Error ? error.message : String(error) })
+  return new LLMError({
+    module: "AISDK",
+    method,
+    reason,
+  })
 }
 
 export const node = makeLocationNode({ service: Service, layer: locationLayer, deps: [] })

packages/core/src/control-plane/move-session.ts

@@ -8,6 +8,7 @@ import { Location } from "../location"
 import { ProjectV2 } from "../project"
 import { SessionV2 } from "../session"
 import { SessionEvent } from "../session/event"
+import { SessionExecution } from "../session/execution"
 import { SessionSchema } from "../session/schema"
 import { SessionStore } from "../session/store"
 import { AbsolutePath, RelativePath } from "../schema"
@@ -73,6 +74,7 @@ const layer = Layer.effect(
     const events = yield* EventV2.Service
     const project = yield* ProjectV2.Service
     const sessions = yield* SessionStore.Service
+    const execution = yield* SessionExecution.Service
 
     const moveSession = Effect.fn("MoveSession.moveSession")(function* (input: Input) {
       const current = yield* sessions.get(input.sessionID)
@@ -86,6 +88,12 @@ const layer = Layer.effect(
         return yield* new DestinationProjectMismatchError({ expected: current.projectID, actual: destination.id })
       }
 
+      // A move must not race active execution: a mid-drain relocation would let
+      // the source Location dispatch a request assembled under stale instructions
+      // and history. Serialize like removal does — stop the drain, then move.
+      yield* execution.interrupt(input.sessionID)
+      yield* execution.awaitIdle(input.sessionID)
+
       const moveChanges = input.moveChanges && source.directory !== destination.directory
       const sourceRepository = moveChanges ? yield* git.repo.discover(current.location.directory) : undefined
       if (moveChanges && !sourceRepository)
@@ -143,5 +151,5 @@ const layer = Layer.effect(
 export const node = makeGlobalNode({
   service: Service,
   layer,
-  deps: [Git.node, EventV2.node, ProjectV2.node, SessionStore.node],
+  deps: [Git.node, EventV2.node, ProjectV2.node, SessionStore.node, SessionExecution.node],
 })

packages/core/src/database/migration.gen.ts

@@ -53,5 +53,6 @@ export const migrations = (
     import("./migration/20260709025533_drop-todo"),
     import("./migration/20260709163752_time_suspended"),
     import("./migration/20260709190621_session_pending_table"),
+    import("./migration/20260710025429_instruction_sync"),
   ])
 ).map((module) => module.default) satisfies DatabaseMigration.Migration[]

packages/core/src/database/migration/20260710025429_instruction_sync.ts

@@ -0,0 +1,86 @@
+import { Effect } from "effect"
+import type { DatabaseMigration } from "../migration"
+
+export default {
+  id: "20260710025429_instruction_sync",
+  up(tx) {
+    return Effect.gen(function* () {
+      yield* tx.run(`ALTER TABLE \`session\` ADD \`fork_seq\` integer;`)
+      yield* tx.run(`PRAGMA foreign_keys=OFF;`)
+      yield* tx.run(`
+        CREATE TABLE \`__new_instruction_entry\` (
+          \`session_id\` text NOT NULL,
+          \`key\` text NOT NULL,
+          \`value\` text,
+          \`removed\` integer DEFAULT false NOT NULL,
+          \`time_created\` integer NOT NULL,
+          \`time_updated\` integer NOT NULL,
+          CONSTRAINT \`instruction_entry_pk\` PRIMARY KEY(\`session_id\`, \`key\`),
+          CONSTRAINT \`fk_instruction_entry_session_id_session_id_fk\` FOREIGN KEY (\`session_id\`) REFERENCES \`session\`(\`id\`) ON DELETE CASCADE
+        );
+      `)
+      yield* tx.run(`
+        INSERT INTO \`__new_instruction_entry\`(
+          \`session_id\`, \`key\`, \`value\`, \`removed\`, \`time_created\`, \`time_updated\`
+        )
+        SELECT \`session_id\`, \`key\`, \`value\`, false, \`time_created\`, \`time_updated\`
+        FROM \`instruction_entry\`;
+      `)
+      yield* tx.run(`DROP TABLE \`instruction_entry\`;`)
+      yield* tx.run(`ALTER TABLE \`__new_instruction_entry\` RENAME TO \`instruction_entry\`;`)
+      yield* tx.run(`PRAGMA foreign_keys=ON;`)
+      yield* tx.run(`
+        CREATE TABLE \`instruction_blob\` (
+          \`hash\` text PRIMARY KEY,
+          \`value\` text
+        );
+      `)
+      yield* tx.run(`
+        CREATE TABLE \`instruction_state\` (
+          \`session_id\` text PRIMARY KEY,
+          \`epoch_start\` integer NOT NULL,
+          \`through_seq\` integer NOT NULL,
+          \`initial_values\` text NOT NULL,
+          \`current_values\` text NOT NULL,
+          CONSTRAINT \`fk_instruction_state_session_id_session_id_fk\` FOREIGN KEY (\`session_id\`) REFERENCES \`session\`(\`id\`) ON DELETE CASCADE
+        );
+      `)
+      // Persisted System rows were exclusively pre-beta instruction prose,
+      // including fork copies whose message IDs no longer match the source event.
+      yield* tx.run(`DELETE FROM \`session_message\` WHERE \`type\` = 'system';`)
+      yield* tx.run(`
+        UPDATE \`session\`
+        SET \`fork_seq\` = COALESCE(
+          (
+            SELECT MIN(\`seq\`) - 1
+            FROM \`event\`
+            WHERE \`aggregate_id\` = \`session\`.\`id\` AND \`seq\` > 0
+          ),
+          (
+            SELECT \`seq\`
+            FROM \`event_sequence\`
+            WHERE \`aggregate_id\` = \`session\`.\`id\`
+          ),
+          0
+        )
+        WHERE \`fork_session_id\` IS NOT NULL;
+      `)
+      yield* tx.run(`
+        UPDATE \`event\`
+        SET
+          \`type\` = 'session.forked.2',
+          \`data\` = json_set(
+            \`data\`,
+            '$.parentSeq',
+            COALESCE(
+              (SELECT \`fork_seq\` FROM \`session\` WHERE \`id\` = \`event\`.\`aggregate_id\`),
+              0
+            )
+          )
+        WHERE \`type\` = 'session.forked.1';
+      `)
+      yield* tx.run(`DELETE FROM \`event\` WHERE \`type\` = 'session.instructions.updated.1';`)
+      yield* tx.run(`DROP TABLE \`instruction_checkpoint\`;`)
+    })
+  },
+} satisfies DatabaseMigration.Migration

packages/core/src/database/schema.gen.ts

@@ -126,25 +126,33 @@ export default {
         );
       `)
       yield* tx.run(`
-        CREATE TABLE \`instruction_checkpoint\` (
-          \`session_id\` text PRIMARY KEY,
-          \`baseline\` text NOT NULL,
-          \`snapshot\` text NOT NULL,
-          \`baseline_seq\` integer NOT NULL,
-          CONSTRAINT \`fk_instruction_checkpoint_session_id_session_id_fk\` FOREIGN KEY (\`session_id\`) REFERENCES \`session\`(\`id\`) ON DELETE CASCADE
+        CREATE TABLE \`instruction_blob\` (
+          \`hash\` text PRIMARY KEY,
+          \`value\` text
         );
       `)
       yield* tx.run(`
         CREATE TABLE \`instruction_entry\` (
           \`session_id\` text NOT NULL,
           \`key\` text NOT NULL,
-          \`value\` text NOT NULL,
+          \`value\` text,
+          \`removed\` integer DEFAULT false NOT NULL,
           \`time_created\` integer NOT NULL,
           \`time_updated\` integer NOT NULL,
           CONSTRAINT \`instruction_entry_pk\` PRIMARY KEY(\`session_id\`, \`key\`),
           CONSTRAINT \`fk_instruction_entry_session_id_session_id_fk\` FOREIGN KEY (\`session_id\`) REFERENCES \`session\`(\`id\`) ON DELETE CASCADE
         );
       `)
+      yield* tx.run(`
+        CREATE TABLE \`instruction_state\` (
+          \`session_id\` text PRIMARY KEY,
+          \`epoch_start\` integer NOT NULL,
+          \`through_seq\` integer NOT NULL,
+          \`initial_values\` text NOT NULL,
+          \`current_values\` text NOT NULL,
+          CONSTRAINT \`fk_instruction_state_session_id_session_id_fk\` FOREIGN KEY (\`session_id\`) REFERENCES \`session\`(\`id\`) ON DELETE CASCADE
+        );
+      `)
       yield* tx.run(`
         CREATE TABLE \`message\` (
           \`id\` text PRIMARY KEY,
@@ -198,6 +206,7 @@ export default {
           \`parent_id\` text,
           \`fork_session_id\` text,
           \`fork_message_id\` text,
+          \`fork_seq\` integer,
           \`slug\` text NOT NULL,
           \`directory\` text NOT NULL,
           \`path\` text,

packages/core/src/event.ts

@@ -1,6 +1,6 @@
 export * as EventV2 from "./event"
 
-import { Cause, Context, DateTime, Effect, Layer, Option, PubSub, Queue, Schema, Stream } from "effect"
+import { Cause, Context, DateTime, Effect, Layer, Option, PubSub, Schema, Stream } from "effect"
 import { Event } from "@opencode-ai/schema/event"
 import type { Data, Definition, Payload } from "@opencode-ai/schema/event"
 import type { EventLog } from "@opencode-ai/schema/event-log"
@@ -89,11 +89,6 @@ const decodeSerializedEvent = (event: SerializedEvent): Payload => {
   }
 }
 
-export class SubscriberOverflowError extends Schema.TaggedErrorClass<SubscriberOverflowError>()(
-  "EventV2.SubscriberOverflow",
-  { capacity: Schema.Int },
-) {}
-
 export const versionedType = Event.versionedType
 export const durable = Event.durable
 export const ephemeral = Event.ephemeral
@@ -137,7 +132,8 @@ export interface Interface {
   ) => Effect.Effect<Payload<D>>
   readonly subscribe: Subscribe
   /**
-   * Durable, ordered, gap-free per-aggregate log read. `follow: false`
+   * Durable, ordered per-aggregate log read. Forked aggregates may reserve an
+   * inherited prefix before their first child-authored event. `follow: false`
    * completes at the end of the log; `follow: true` replays then transitions
    * to live. Both modes emit one `Synced` marker at the captured replay
    * watermark.
@@ -166,27 +162,6 @@ export interface Interface {
 
 export class Service extends Context.Service<Service, Interface>()("@opencode/Event") {}
 
-export const liveBounded = (
-  events: Interface,
-  options: { readonly capacity: number; readonly accept?: (event: Payload) => boolean },
-) =>
-  Effect.gen(function* () {
-    const queue = yield* Queue.dropping<Payload, SubscriberOverflowError>(options.capacity)
-    const unsubscribe = yield* events.listen((event) =>
-      options.accept && !options.accept(event)
-        ? Effect.void
-        : Queue.offer(queue, event).pipe(
-            Effect.flatMap((accepted) =>
-              accepted
-                ? Effect.void
-                : Queue.fail(queue, new SubscriberOverflowError({ capacity: options.capacity })).pipe(Effect.asVoid),
-            ),
-          ),
-    )
-    yield* Effect.addFinalizer(() => unsubscribe.pipe(Effect.andThen(Queue.shutdown(queue)), Effect.asVoid))
-    return Stream.fromQueue(queue)
-  })
-
 export interface LayerOptions {
   readonly beforeAggregateRead?: (aggregateID: string) => Effect.Effect<void>
   /** Maximum durable rows read per page while replaying or tailing an aggregate log. */
@@ -203,7 +178,6 @@ export const layerWith = (options?: LayerOptions) =>
         typed: new Map<string, PubSub.PubSub<Payload>>(),
       }
       const projectors = new Map<string, Subscriber[]>()
-      // TODO: Bind durable projectors to exact type+version before supporting incompatible historical payloads.
       const listeners = new Array<Subscriber>()
       const { db } = yield* Database.Service
       const logReadPageSize = options?.logReadPageSize ?? 512
@@ -260,7 +234,7 @@ export const layerWith = (options?: LayerOptions) =>
                   }),
                 )
               }
-              const list = projectors.get(event.type) ?? []
+              const list = projectors.get(versionedType(definition.type, durable.version)) ?? []
               return yield* Effect.uninterruptible(
                 Effect.gen(function* () {
                   const committed = yield* db
@@ -515,18 +489,6 @@ export const layerWith = (options?: LayerOptions) =>
               }),
             )
           }
-          const start = events[0]?.seq ?? 0
-          for (const [index, event] of events.entries()) {
-            const seq = start + index
-            if (event.seq !== seq) {
-              yield* Effect.die(
-                new InvalidDurableEventError({
-                  type: event.type,
-                  message: `Replay sequence mismatch at index ${index}: expected ${seq}, got ${event.seq}`,
-                }),
-              )
-            }
-          }
           for (const event of events) {
             yield* replay(event, options)
           }
@@ -727,9 +689,10 @@ export const layerWith = (options?: LayerOptions) =>
 
       const project = <D extends Definition>(definition: D, projector: Subscriber<D>): Effect.Effect<void> =>
         Effect.sync(() => {
-          const list = projectors.get(definition.type) ?? []
+          const key = definition.durable ? versionedType(definition.type, definition.durable.version) : definition.type
+          const list = projectors.get(key) ?? []
           list.push((event) => projector(event as Payload<D>))
-          projectors.set(definition.type, list)
+          projectors.set(key, list)
         })
 
       return Service.of({

packages/core/src/filesystem/search.ts

@@ -128,6 +128,8 @@ export const fffLayer = Layer.effect(
         Fff.create({
           basePath: location.directory,
           aiMode: true,
+          disableMmapCache: true,
+          disableContentIndexing: true,
         }),
       catch: (cause) => cause,
     }).pipe(
@@ -230,6 +232,13 @@ export const fffLayer = Layer.effect(
   }),
 )
 
-const layer = Layer.unwrap(Effect.sync(() => (Flag.OPENCODE_DISABLE_FFF || !Fff.available() ? ripgrepLayer : fffLayer)))
+const layer = Layer.unwrap(
+  Effect.gen(function* () {
+    if (Flag.OPENCODE_DISABLE_FFF || !Fff.available()) return ripgrepLayer
+    const location = yield* Location.Service
+    // Non-VCS locations can contain many repositories, so avoid eagerly content-indexing the entire aggregate tree.
+    return location.vcs ? fffLayer : ripgrepLayer
+  }),
+)
 
 export const node = makeLocationNode({ service: Service, layer, deps: [FSUtil.node, Location.node, Ripgrep.node] })

packages/core/src/generate.ts

@@ -1,6 +1,6 @@
 export * as Generate from "./generate"
 
-import { LLM, LLMClient, type LLMError } from "@opencode-ai/llm"
+import { LLM, LLMClient, LLMError } from "@opencode-ai/llm"
 import { Context, Effect, Layer, Schema } from "effect"
 import { Catalog } from "./catalog"
 import { makeLocationNode } from "./effect/app-node"

packages/core/src/git.ts

@@ -189,16 +189,14 @@ const layer = Layer.effect(
       if (!dotgit) return undefined
 
       const cwd = path.dirname(dotgit)
-      const git = run(cwd, proc)
-      const topLevel = yield* git(["rev-parse", "--show-toplevel"])
-      const gitDir = yield* git(["rev-parse", "--git-dir"])
-      const commonDir = yield* git(["rev-parse", "--git-common-dir"])
-      if (gitDir.exitCode !== 0 || commonDir.exitCode !== 0) return undefined
+      const result = yield* run(cwd, proc)(["rev-parse", "--git-dir", "--git-common-dir", "--show-toplevel"])
+      const [gitDir, commonDir, topLevel] = result.text.split(/\r?\n/)
+      if (!gitDir || !commonDir) return undefined
 
       return new Repository({
-        worktree: AbsolutePath.make(topLevel.exitCode === 0 ? resolvePath(cwd, topLevel.text) : cwd),
-        gitDirectory: AbsolutePath.make(resolvePath(cwd, gitDir.text)),
-        commonDirectory: AbsolutePath.make(resolvePath(cwd, commonDir.text)),
+        worktree: AbsolutePath.make(topLevel ? resolvePath(cwd, topLevel) : cwd),
+        gitDirectory: AbsolutePath.make(resolvePath(cwd, gitDir)),
+        commonDirectory: AbsolutePath.make(resolvePath(cwd, commonDir)),
       })
     })
 

packages/core/src/github-copilot/models.ts

@@ -0,0 +1,214 @@
+export * as CopilotModels from "./models"
+
+import { Money } from "@opencode-ai/schema/money"
+import { Option, Schema } from "effect"
+import { ModelV2 } from "../model"
+import { ProviderV2 } from "../provider"
+
+const RemoteModel = Schema.Struct({
+  model_picker_enabled: Schema.Boolean,
+  id: Schema.String,
+  name: Schema.String,
+  version: Schema.String,
+  supported_endpoints: Schema.optional(Schema.Array(Schema.String)),
+  policy: Schema.optional(Schema.Struct({ state: Schema.optional(Schema.String) })),
+  billing: Schema.optional(
+    Schema.Struct({
+      token_prices: Schema.optional(
+        Schema.Struct({
+          batch_size: Schema.Number,
+          default: Schema.Struct({
+            cache_price: Schema.Number,
+            input_price: Schema.Number,
+            output_price: Schema.Number,
+          }),
+        }),
+      ),
+    }),
+  ),
+  capabilities: Schema.Struct({
+    family: Schema.String,
+    limits: Schema.optional(
+      Schema.Struct({
+        max_context_window_tokens: Schema.optional(Schema.Number),
+        max_output_tokens: Schema.optional(Schema.Number),
+        max_prompt_tokens: Schema.optional(Schema.Number),
+        vision: Schema.optional(
+          Schema.Struct({
+            max_prompt_image_size: Schema.Number,
+            max_prompt_images: Schema.Number,
+            supported_media_types: Schema.Array(Schema.String),
+          }),
+        ),
+      }),
+    ),
+    supports: Schema.Struct({
+      adaptive_thinking: Schema.optional(Schema.Boolean),
+      max_thinking_budget: Schema.optional(Schema.Number),
+      min_thinking_budget: Schema.optional(Schema.Number),
+      reasoning_effort: Schema.optional(Schema.Array(Schema.String)),
+      streaming: Schema.optional(Schema.Boolean),
+      structured_outputs: Schema.optional(Schema.Boolean),
+      tool_calls: Schema.optional(Schema.Boolean),
+      vision: Schema.optional(Schema.Boolean),
+    }),
+  }),
+})
+
+const Response = Schema.Struct({ data: Schema.Array(Schema.Unknown) })
+const decodeResponse = Schema.decodeUnknownSync(Response)
+const decodeModel = Schema.decodeUnknownOption(RemoteModel)
+
+type RemoteModel = typeof RemoteModel.Type
+type UsableModel = RemoteModel & {
+  capabilities: RemoteModel["capabilities"] & {
+    limits: NonNullable<RemoteModel["capabilities"]["limits"]> & {
+      max_output_tokens: number
+      max_prompt_tokens: number
+    }
+    supports: RemoteModel["capabilities"]["supports"] & { tool_calls: boolean }
+  }
+}
+
+export async function get(baseURL: string, headers: RequestInit["headers"], existing: readonly ModelV2.Info[]) {
+  const response = await fetch(`${baseURL}/models`, {
+    headers,
+    signal: AbortSignal.timeout(5_000),
+  })
+  if (!response.ok) throw new Error(`Failed to fetch Copilot models: ${response.status}`)
+
+  const remote = new Map(
+    decodeResponse(await response.json()).data.flatMap((raw) => {
+      const model = Option.getOrUndefined(decodeModel(raw))
+      return model && usable(model) ? ([[model.id, model]] as const) : []
+    }),
+  )
+  const result = new Map(existing.map((model) => [model.id, model]))
+
+  // Keep aliases and local metadata, but only when their advertised API model
+  // still exists. A partial or malformed item cannot create a broken model.
+  for (const [id, model] of result) {
+    const current = remote.get(model.modelID)
+    if (!current) {
+      result.delete(id)
+      continue
+    }
+    result.set(id, build(id, current, baseURL, model))
+  }
+
+  for (const [id, model] of remote) {
+    const key = ModelV2.ID.make(id)
+    if (result.has(key)) continue
+    result.set(key, build(key, model, baseURL))
+  }
+
+  return result
+}
+
+function usable(model: RemoteModel): model is UsableModel {
+  return (
+    model.policy?.state !== "disabled" &&
+    model.capabilities.limits?.max_output_tokens !== undefined &&
+    model.capabilities.limits.max_prompt_tokens !== undefined &&
+    model.capabilities.supports.tool_calls !== undefined
+  )
+}
+
+function build(id: ModelV2.ID, remote: UsableModel, baseURL: string, previous?: ModelV2.Info) {
+  const messages = remote.supported_endpoints?.includes("/v1/messages") ?? false
+  const endpoint = messages
+    ? "messages"
+    : remote.supported_endpoints?.includes("/responses")
+      ? "responses"
+      : remote.supported_endpoints?.includes("/chat/completions")
+        ? "chat"
+        : undefined
+  const image =
+    (remote.capabilities.supports.vision ?? false) ||
+    (remote.capabilities.limits.vision?.supported_media_types ?? []).some((item) => item.startsWith("image/"))
+  const prices = remote.billing?.token_prices
+  // Copilot reports AIC per billing batch; OpenCode stores USD per million tokens.
+  const usdPerMillion = prices && prices.batch_size > 0 ? 10_000 / prices.batch_size : 0
+  const version = remote.version.startsWith(`${remote.id}-`)
+    ? remote.version.slice(remote.id.length + 1)
+    : remote.version
+  const released = previous?.time.released || Date.parse(version)
+
+  return ModelV2.Info.make({
+    ...ModelV2.Info.empty(ProviderV2.ID.githubCopilot, id),
+    id,
+    modelID: ModelV2.ID.make(remote.id),
+    providerID: ProviderV2.ID.githubCopilot,
+    family: previous?.family ?? ModelV2.Family.make(remote.capabilities.family),
+    name: previous?.name ?? remote.name,
+    package: ProviderV2.aisdk(messages ? "@ai-sdk/anthropic" : "@ai-sdk/github-copilot"),
+    settings: ProviderV2.mergeOverlay(previous?.settings, {
+      baseURL: messages ? `${baseURL}/v1` : baseURL,
+      ...(endpoint ? { endpoint } : {}),
+    }),
+    headers: previous?.headers,
+    body: previous?.body,
+    capabilities: {
+      tools: remote.capabilities.supports.tool_calls,
+      input: image ? ["text", "image"] : ["text"],
+      output: ["text"],
+    },
+    variants: variants(remote, messages),
+    time: { released: Number.isFinite(released) ? released : 0 },
+    cost: [
+      {
+        input: Money.USDPerMillionTokens.make((prices?.default.input_price ?? 0) * usdPerMillion),
+        output: Money.USDPerMillionTokens.make((prices?.default.output_price ?? 0) * usdPerMillion),
+        cache: {
+          read: Money.USDPerMillionTokens.make((prices?.default.cache_price ?? 0) * usdPerMillion),
+          write: Money.USDPerMillionTokens.zero,
+        },
+      },
+    ],
+    status: "active",
+    enabled: remote.model_picker_enabled,
+    limit: {
+      context: remote.capabilities.limits.max_context_window_tokens ?? remote.capabilities.limits.max_prompt_tokens,
+      input: remote.capabilities.limits.max_prompt_tokens,
+      output: remote.capabilities.limits.max_output_tokens,
+    },
+  })
+}
+
+function variants(remote: UsableModel, messages: boolean): ModelV2.Info["variants"] {
+  const efforts = remote.capabilities.supports.reasoning_effort ?? []
+  if (!messages && efforts.length) {
+    return efforts.map((effort) => ({
+      id: ModelV2.VariantID.make(effort),
+      settings: {
+        reasoningEffort: effort,
+        reasoningSummary: "auto",
+        include: ["reasoning.encrypted_content"],
+      },
+    }))
+  }
+  if (efforts.length && remote.capabilities.supports.adaptive_thinking) {
+    return efforts.map((effort) => ({
+      id: ModelV2.VariantID.make(effort),
+      settings: {
+        thinking: {
+          type: "adaptive",
+          ...(remote.id.includes("opus-4.7") ? { display: "summarized" } : {}),
+        },
+        effort,
+      },
+    }))
+  }
+  const max = remote.capabilities.supports.max_thinking_budget
+  if (max === undefined) return []
+  return [
+    {
+      id: ModelV2.VariantID.make("max"),
+      settings: { thinking: { type: "enabled", budgetTokens: max - 1 } },
+    },
+    {
+      id: ModelV2.VariantID.make("high"),
+      settings: { thinking: { type: "enabled", budgetTokens: Math.floor(max / 2) } },
+    },
+  ]
+}

packages/core/src/instruction-discovery.ts

@@ -31,15 +31,17 @@ const layer = Layer.effect(
     const global = yield* Global.Service
     const location = yield* Location.Service
 
-    const source = (value: ReadonlyArray<File> | Instructions.Unavailable) =>
-      Instructions.make({
+    const source = (value: ReadonlyArray<File> | Instructions.Unavailable | Instructions.Removed) =>
+      Instructions.make<ReadonlyArray<File>>({
         key,
         codec: Schema.toCodecJson(Files),
-        load: Effect.succeed(value),
-        baseline: render,
-        update: (_previous, current) =>
-          `These instructions replace all previously loaded ambient instructions.\n\n${render(current)}`,
-        removed: () => "Previously loaded instructions no longer apply.",
+        read: Effect.succeed(value),
+        render: {
+          initial: render,
+          changed: (_previous, current) =>
+            `These instructions replace all previously loaded ambient instructions.\n\n${render(current)}`,
+          removed: () => "Previously loaded instructions no longer apply.",
+        },
       })
 
     const observe = Effect.fn("InstructionDiscovery.observe")(function* () {
@@ -82,11 +84,7 @@ const layer = Layer.effect(
       load: () =>
         observe().pipe(
           Effect.map((files) =>
-            files === Instructions.unavailable
-              ? source(files)
-              : files.length === 0
-                ? Instructions.empty
-                : source(files),
+            Array.isArray(files) && files.length === 0 ? source(Instructions.removed) : source(files),
           ),
           Effect.catch(() => Effect.succeed(source(Instructions.unavailable))),
           Effect.catchDefect(() => Effect.succeed(source(Instructions.unavailable))),

packages/core/src/instructions/builtins.ts

@@ -15,29 +15,34 @@ const layer = Layer.effect(
   Service,
   Effect.gen(function* () {
     const location = yield* Location.Service
-    const environment = [
-      "<env>",
-      `  Working directory: ${location.directory}`,
-      `  Workspace root folder: ${location.project.directory}`,
-      `  Is directory a git repo: ${location.vcs?.type === "git" ? "yes" : "no"}`,
-      `  Platform: ${process.platform}`,
-      "</env>",
-    ].join("\n")
     const instructions = Instructions.combine([
       Instructions.make({
         key: Instructions.Key.make("core/environment"),
         codec: Schema.toCodecJson(Schema.String),
-        load: Effect.succeed(environment),
-        baseline: (environment) =>
-          ["Here is some useful information about the environment you are running in:", environment].join("\n"),
-        update: (_previous, environment) => ["The environment you are running in is now:", environment].join("\n"),
+        read: Effect.sync(() =>
+          [
+            "<env>",
+            `  Working directory: ${location.directory}`,
+            `  Workspace root folder: ${location.project.directory}`,
+            `  Is directory a git repo: ${location.vcs?.type === "git" ? "yes" : "no"}`,
+            `  Platform: ${process.platform}`,
+            "</env>",
+          ].join("\n"),
+        ),
+        render: {
+          initial: (environment) =>
+            ["Here is some useful information about the environment you are running in:", environment].join("\n"),
+          changed: (_previous, environment) => ["The environment you are running in is now:", environment].join("\n"),
+        },
       }),
       Instructions.make({
         key: Instructions.Key.make("core/date"),
         codec: Schema.toCodecJson(Schema.String),
-        load: DateTime.nowAsDate.pipe(Effect.map((date) => date.toDateString())),
-        baseline: (date) => `Today's date: ${date}`,
-        update: (_previous, date) => `Today's date is now: ${date}`,
+        read: DateTime.nowAsDate.pipe(Effect.map((date) => date.toDateString())),
+        render: {
+          initial: (date) => `Today's date: ${date}`,
+          changed: (_previous, date) => `Today's date is now: ${date}`,
+        },
       }),
     ])
 

packages/core/src/instructions/index.ts

@@ -1,80 +1,70 @@
 export * as Instructions from "./index"
 
-import { Effect, Option, Schema } from "effect"
+import { createHash } from "crypto"
+import { Instruction } from "@opencode-ai/schema/instruction"
+import { Data, Effect, Option, Schema } from "effect"
 
-/**
- * Models privileged instructions as independently refreshable typed sources.
- *
- * `Source<A>` describes how to observe, compare, and render one value. `make`
- * closes over `A`, producing opaque `Instructions` that compose uniformly with
- * instructions built from other value types.
- *
- * The durable `Applied` record tracks what the model was last told, per source:
- * it is the model's current belief. Interpreters uphold one invariant —
- * `reconcile` never rewrites the baseline; it only narrates drift as update
- * text. Only `rebaseline` (compaction) and `initialize` (first step) produce
- * baseline text.
- *
- * Returning `unavailable` means observation failed temporarily. It differs from
- * removing a source from the instructions: the model's prior belief stands.
- * `reconcile` retains the applied value silently, and `rebaseline` restates the
- * belief by rendering the last-applied value instead of a live observation.
- *
- * @module
- */
+export const Key = Instruction.Key
+export type Key = Instruction.Key
+export const Hash = Instruction.Hash
+export type Hash = Instruction.Hash
+export const Values = Instruction.Values
+export type Values = Instruction.Values
+export const Delta = Instruction.Delta
+export type Delta = Instruction.Delta
 
-/** Stable namespaced identity for one independently refreshable instruction source. */
-export const Key = Schema.String.check(Schema.isPattern(/^[a-z0-9][a-z0-9._-]*\/[a-z0-9][a-z0-9._/-]*$/)).pipe(
-  Schema.brand("Instructions.Key"),
-)
-export type Key = typeof Key.Type
+type NonValue = Data.TaggedEnum<{ Unavailable: {}; Removed: {} }>
+const NonValue = Data.taggedEnum<NonValue>()
 
-/** Indicates that a source could not be observed without treating it as removed. */
-export const unavailable = Symbol.for("@opencode/Instructions.Unavailable")
+/** The read failed temporarily; the stored value stands. */
+export const unavailable = NonValue.Unavailable()
 export type Unavailable = typeof unavailable
 
-/** Defines one typed source before its value type is hidden by `make`. */
-export interface Source<A> {
+/** An observed absence: the source exists but its value is gone. */
+export const removed = NonValue.Removed()
+export type Removed = typeof removed
+
+/**
+ * One composable instruction source over canonical JSON — the same
+ * representation that is hashed, stored, and replayed. `make` builds one from
+ * a typed definition; renderers returning `undefined` skip (undecodable or
+ * unrenderable historical values).
+ */
+export interface Source {
   readonly key: Key
-  readonly codec: Schema.Codec<A, Schema.Json, never, never>
-  readonly load: Effect.Effect<A | Unavailable>
-  readonly baseline: (current: A) => string
-  readonly update: (previous: A, current: A) => string
-  readonly removed?: (previous: A) => string
+  readonly read: Effect.Effect<Schema.Json | Unavailable | Removed>
+  readonly initial: (value: Schema.Json) => string | undefined
+  readonly changed: (previous: Schema.Json, current: Schema.Json) => string | undefined
+  readonly removed: (previous: Schema.Json) => string | undefined
 }
 
-const InstructionsTypeId: unique symbol = Symbol.for("@opencode/Instructions")
-
-/** Opaque carrier for composable instruction sources. */
-export interface Instructions {
-  readonly [InstructionsTypeId]: ReadonlyArray<PackedSource>
+export declare namespace Source {
+  /** The typed definition supplied when constructing a source. */
+  export interface Definition<A> {
+    readonly key: Key
+    readonly codec: Schema.Codec<A, Schema.Json>
+    readonly read: Effect.Effect<A | Unavailable | Removed>
+    readonly render: {
+      readonly initial: (current: A) => string
+      readonly changed: (previous: A, current: A) => string
+      readonly removed?: (previous: A) => string
+    }
+  }
 }
 
-/** The value last applied to the model for one admitted source. */
-export const AppliedSource = Schema.Struct({
-  value: Schema.Json,
-  removed: Schema.optional(Schema.NonEmptyString),
-})
-export type AppliedSource = typeof AppliedSource.Type
+/** Ordered sources; identical values render identical bytes. */
+export type Instructions = ReadonlyArray<Source>
 
-/** Durable record of what the model currently believes, per source. */
-export const Applied = Schema.Record(Key, AppliedSource)
-export type Applied = Readonly<Record<string, AppliedSource>>
+export type ReadResult = ReadonlyArray<{
+  readonly key: Key
+  readonly value: Schema.Json | Unavailable | Removed
+}>
 
-/** A rendered baseline together with the applied values it was rendered from. */
-export interface Baseline {
-  readonly text: string
-  readonly applied: Applied
+export interface Admission {
+  readonly delta: Delta
+  readonly blobs: Readonly<Record<string, Schema.Json>>
 }
 
-export interface Updated {
-  readonly _tag: "Updated"
-  readonly text: string
-  readonly applied: Applied
-}
-
-export type ReconcileResult = { readonly _tag: "Unchanged" } | Updated
-
 export class InitializationBlocked extends Schema.TaggedErrorClass<InitializationBlocked>()(
   "Instructions.InitializationBlocked",
   { keys: Schema.Array(Key) },
@@ -92,71 +82,140 @@ export class DuplicateKeyError extends Schema.TaggedErrorClass<DuplicateKeyError
   }
 }
 
-interface PackedSource {
-  readonly key: Key
-  readonly load: Effect.Effect<Observed | Unavailable>
-  /** Restates the model's belief from a last-applied value when the source cannot be observed. */
-  readonly recall: (stored: AppliedSource) => string | undefined
-}
+export const empty: Instructions = []
 
-interface Observed {
-  readonly applied: AppliedSource
-  readonly baseline: () => string
-  /** `undefined` means unchanged. An undecodable previous value re-renders the baseline (treat-as-new). */
-  readonly update: (previous: AppliedSource) => string | undefined
-}
-
-interface Entry {
-  readonly key: Key
-  readonly recall: PackedSource["recall"]
-  readonly observed: Observed | Unavailable
-}
-
-/** The identity instruction set. */
-export const empty = instructions([])
-
-/** Closes a typed source into instructions that compose with differently typed sources. */
-export function make<A>(source: Source<A>): Instructions {
+/** Closes a typed definition into one `Source`, so differently typed sources compose. */
+export function make<A>(source: Source.Definition<A>): Instructions {
   const decode = Schema.decodeUnknownOption(source.codec)
   const encode = Schema.encodeSync(source.codec)
-  const equivalent = Schema.toEquivalence(source.codec)
-  const baseline = (value: A) => requireText(source.key, "baseline", source.baseline(value))
-  return instructions([
+  const initial = (value: A) => requireText(source.key, "initial", source.render.initial(value))
+  const decodeValue = (value: Schema.Json) => Option.getOrUndefined(decode(value))
+  return [
     {
       key: source.key,
-      recall: (stored) =>
-        Option.match(decode(stored.value), {
-          onNone: () => undefined,
-          onSome: baseline,
-        }),
-      load: source.load.pipe(
+      read: source.read.pipe(
         Effect.map((value) => {
-          if (isUnavailable(value)) return value
-          return {
-            applied: {
-              value: encode(value),
-              ...(source.removed ? { removed: requireText(source.key, "removal", source.removed(value)) } : {}),
-            },
-            baseline: () => baseline(value),
-            update: (previous) =>
-              Option.match(decode(previous.value), {
-                onNone: () => baseline(value),
-                onSome: (decoded) =>
-                  equivalent(decoded, value)
-                    ? undefined
-                    : requireText(source.key, "update", source.update(decoded, value)),
-              }),
-          } satisfies Observed
+          if (isUnavailable(value)) return unavailable
+          if (isRemoved(value)) return removed
+          return encode(value)
         }),
       ),
+      initial: (value) => {
+        const decoded = decodeValue(value)
+        return decoded === undefined ? undefined : initial(decoded)
+      },
+      changed: (previous, current) => {
+        const before = decodeValue(previous)
+        const after = decodeValue(current)
+        if (after === undefined) return undefined
+        if (before === undefined) return initial(after)
+        return requireText(source.key, "changed", source.render.changed(before, after))
+      },
+      removed: (previous) => {
+        const decoded = decodeValue(previous)
+        return decoded === undefined || source.render.removed === undefined
+          ? undefined
+          : requireText(source.key, "removed", source.render.removed(decoded))
+      },
     },
-  ])
+  ]
+}
+
+export function combine(values: ReadonlyArray<Instructions>): Instructions {
+  const sources = values.flat()
+  const keys = new Set<Key>()
+  for (const source of sources) {
+    if (keys.has(source.key)) throw new DuplicateKeyError({ key: source.key })
+    keys.add(source.key)
+  }
+  return sources
+}
+
+export function read(value: Instructions): Effect.Effect<ReadResult> {
+  return Effect.forEach(
+    value,
+    (source) => source.read.pipe(Effect.map((observed) => ({ key: source.key, value: observed }))),
+    { concurrency: "unbounded" },
+  )
+}
+
+export function diff(observed: ReadResult, previous?: Values): Effect.Effect<Admission, InitializationBlocked> {
+  const blocked = previous ? [] : observed.flatMap((entry) => (isUnavailable(entry.value) ? [entry.key] : []))
+  if (blocked.length > 0) return Effect.fail(new InitializationBlocked({ keys: blocked }))
+  const delta: Record<string, Hash | Instruction.Removed> = {}
+  const blobs: Record<string, Schema.Json> = {}
+  for (const entry of observed) {
+    if (isUnavailable(entry.value)) continue
+    if (isRemoved(entry.value)) {
+      if (previous && Object.hasOwn(previous, entry.key)) delta[entry.key] = Instruction.removed
+      continue
+    }
+    const next = hash(entry.value)
+    if (previous?.[entry.key] === next) continue
+    delta[entry.key] = next
+    blobs[next] = entry.value
+  }
+  return Effect.succeed({ delta, blobs })
+}
+
+export function renderInitial(value: Instructions, values: Readonly<Record<string, Schema.Json>>) {
+  return render(
+    value.flatMap((source) => {
+      if (!Object.hasOwn(values, source.key)) return []
+      const text = source.initial(values[source.key])
+      return text === undefined ? [] : [text]
+    }),
+  )
+}
+
+export function renderUpdate(
+  value: Instructions,
+  previous: Readonly<Record<string, Schema.Json>>,
+  delta: Readonly<Record<string, Option.Option<Schema.Json>>>,
+) {
+  return render(
+    value.flatMap((source) => {
+      if (!Object.hasOwn(delta, source.key)) return []
+      const current = delta[source.key]
+      if (Option.isNone(current)) {
+        if (!Object.hasOwn(previous, source.key)) return []
+        const text = source.removed(previous[source.key])
+        return text === undefined ? [] : [text]
+      }
+      const next = current.value
+      const text = Object.hasOwn(previous, source.key)
+        ? source.changed(previous[source.key], next)
+        : source.initial(next)
+      return text === undefined ? [] : [text]
+    }),
+  )
+}
+
+export function hash(value: Schema.Json) {
+  return Hash.make(createHash("sha256").update(canonical(value)).digest("hex"))
+}
+
+export function applyDelta(
+  values: Readonly<Record<string, Schema.Json>>,
+  delta: Readonly<Record<string, Option.Option<Schema.Json>>>,
+): Readonly<Record<string, Schema.Json>> {
+  const result: Record<string, Schema.Json> = { ...values }
+  for (const [key, value] of Object.entries(delta)) {
+    if (Option.isNone(value)) delete result[key]
+    else result[key] = value.value
+  }
+  return result
+}
+
+export function applyHashDelta(values: Values, delta: Delta): Values {
+  const result: Record<string, Hash> = { ...values }
+  for (const [key, value] of Object.entries(delta)) {
+    if (value === Instruction.removed) delete result[key]
+    else result[key] = value
+  }
+  return result
 }
 
-/**
- * Keyed three-way diff for list-shaped sources rendering delta updates.
- * `changed` compares two values sharing a key; entries equal under it are dropped.
- */
 export function diffByKey<A>(
   previous: ReadonlyArray<A>,
   current: ReadonlyArray<A>,
@@ -179,129 +238,31 @@ export function diffByKey<A>(
   }
 }
 
-/** Combines instructions in order and rejects duplicate source keys immediately. */
-export function combine(values: ReadonlyArray<Instructions>): Instructions {
-  const sources = values.flatMap((value) => value[InstructionsTypeId])
-  assertUniqueKeys(sources)
-  return instructions(sources)
-}
-
-const observe = (value: Instructions) =>
-  Effect.forEach(
-    value[InstructionsTypeId],
-    (source) =>
-      source.load.pipe(Effect.map((observed): Entry => ({ key: source.key, recall: source.recall, observed }))),
-    { concurrency: "unbounded" },
-  )
-
-/** Creates the first baseline. Blocks rather than admit a baseline missing an unobservable source. */
-export function initialize(value: Instructions): Effect.Effect<Baseline, InitializationBlocked> {
-  return observe(value).pipe(
-    Effect.flatMap((entries) => {
-      const blocked = entries.flatMap((entry) => (entry.observed === unavailable ? [entry.key] : []))
-      if (blocked.length > 0) return new InitializationBlocked({ keys: blocked })
-      const parts: string[] = []
-      const applied: Record<string, AppliedSource> = {}
-      for (const entry of entries) {
-        if (entry.observed === unavailable) continue
-        parts.push(entry.observed.baseline())
-        applied[entry.key] = entry.observed.applied
-      }
-      return Effect.succeed({ text: render(parts), applied })
-    }),
-  )
-}
-
-/** Narrates drift between current source values and the model's beliefs. Never rewrites the baseline. */
-export function reconcile(value: Instructions, previous: Applied): Effect.Effect<ReconcileResult> {
-  return observe(value).pipe(
-    Effect.map((entries): ReconcileResult => {
-      const updates: string[] = []
-      const applied: Record<string, AppliedSource> = {}
-      for (const entry of entries) {
-        const stored = get(previous, entry.key)
-        if (entry.observed === unavailable) {
-          // The prior belief stands while the source cannot be observed.
-          if (stored) applied[entry.key] = stored
-          continue
-        }
-        if (!stored) {
-          updates.push(entry.observed.baseline())
-          applied[entry.key] = entry.observed.applied
-          continue
-        }
-        const text = entry.observed.update(stored)
-        if (text === undefined) {
-          applied[entry.key] = stored
-          continue
-        }
-        updates.push(text)
-        applied[entry.key] = entry.observed.applied
-      }
-      const keys = new Set<string>(entries.map((entry) => entry.key))
-      for (const key of Object.keys(previous).sort()) {
-        if (keys.has(key)) continue
-        const removed = previous[key].removed
-        // An unannounced removal retains the belief; it clears at the next rebaseline.
-        if (removed === undefined) applied[key] = previous[key]
-        else updates.push(removed)
-      }
-      if (updates.length === 0) return { _tag: "Unchanged" }
-      return { _tag: "Updated", text: render(updates), applied }
-    }),
-  )
-}
-
-/** Rebuilds the baseline, restating unobservable sources from the model's last-applied beliefs. */
-export function rebaseline(value: Instructions, previous: Applied): Effect.Effect<Baseline> {
-  return observe(value).pipe(
-    Effect.map((entries): Baseline => {
-      const parts: string[] = []
-      const applied: Record<string, AppliedSource> = {}
-      for (const entry of entries) {
-        if (entry.observed !== unavailable) {
-          parts.push(entry.observed.baseline())
-          applied[entry.key] = entry.observed.applied
-          continue
-        }
-        const stored = get(previous, entry.key)
-        if (!stored) continue
-        const text = entry.recall(stored)
-        // An undecodable belief cannot be restated; the source re-announces when observable again.
-        if (text === undefined) continue
-        parts.push(text)
-        applied[entry.key] = stored
-      }
-      return { text: render(parts), applied }
-    }),
-  )
-}
-
-function instructions(sources: ReadonlyArray<PackedSource>): Instructions {
-  return { [InstructionsTypeId]: sources }
-}
-
 function render(parts: ReadonlyArray<string>) {
   return parts.join("\n\n")
 }
 
-function get(applied: Applied, key: Key) {
-  return Object.hasOwn(applied, key) ? applied[key] : undefined
-}
-
+// Reference-equality guards: `A` in a typed source may itself be JSON shaped
+// like these singletons, so identity, never structure, discriminates.
 function isUnavailable(value: unknown): value is Unavailable {
   return value === unavailable
 }
 
+function isRemoved(value: unknown): value is Removed {
+  return value === removed
+}
+
+function canonical(value: Schema.Json): string {
+  if (Array.isArray(value)) return `[${value.map(canonical).join(",")}]`
+  if (value !== null && typeof value === "object")
+    return `{${Object.entries(value)
+      .sort(([a], [b]) => (a < b ? -1 : a > b ? 1 : 0))
+      .map(([key, entry]) => `${JSON.stringify(key)}:${canonical(entry)}`)
+      .join(",")}}`
+  return JSON.stringify(value)
+}
+
 function requireText(key: Key, kind: string, text: string) {
   if (text.length === 0) throw new Error(`Instruction source ${key} rendered an empty ${kind}`)
   return text
 }
-
-function assertUniqueKeys(sources: ReadonlyArray<PackedSource>) {
-  const keys = new Set<Key>()
-  for (const source of sources) {
-    if (keys.has(source.key)) throw new DuplicateKeyError({ key: source.key })
-    keys.add(source.key)
-  }
-}

packages/core/src/integration.ts

@@ -303,7 +303,7 @@ const layer = Layer.effect(
     }
 
     const project = (entry: Entry, connections: IntegrationConnection.Info[]) =>
-      new Info({
+      Info.make({
         id: entry.ref.id,
         name: entry.ref.name,
         methods: entry.methods,

packages/core/src/mcp/guidance.ts

@@ -70,8 +70,19 @@ export const layer = Layer.effect(
       load: Effect.fn("McpGuidance.load")(function* (selection) {
         const agent = selection.info
         if (!agent) return Instructions.empty
+        const source = (value: ReadonlyArray<Summary> | Instructions.Removed) =>
+          Instructions.make<ReadonlyArray<Summary>>({
+            key: Instructions.Key.make("core/mcp-guidance"),
+            codec: Schema.toCodecJson(Schema.Array(Summary)),
+            read: Effect.succeed(value),
+            render: {
+              initial: render,
+              changed: update,
+              removed: () => "MCP server instructions are no longer available.",
+            },
+          })
         if (Flag.CODEMODE_ENABLED && PermissionV2.evaluate("execute", "*", agent.permissions).effect === "deny")
-          return Instructions.empty
+          return source(Instructions.removed)
         const [instructions, tools] = yield* Effect.all([mcp.instructions(), mcp.tools()], {
           concurrency: "unbounded",
         })
@@ -88,15 +99,8 @@ export const layer = Layer.effect(
             )
           })
           .map((item) => ({ server: item.server, instructions: item.instructions }))
-        if (visible.length === 0) return Instructions.empty
-        return Instructions.make({
-          key: Instructions.Key.make("core/mcp-guidance"),
-          codec: Schema.toCodecJson(Schema.Array(Summary)),
-          load: Effect.succeed(visible),
-          baseline: render,
-          update,
-          removed: () => "MCP server instructions are no longer available.",
-        })
+          .toSorted((a, b) => a.server.localeCompare(b.server))
+        return source(visible.length === 0 ? Instructions.removed : visible)
       }),
     })
   }),

packages/core/src/plugin.ts

@@ -21,10 +21,14 @@ import { ToolHooks } from "./tool/hooks"
 import { PluginHooks } from "./plugin/hooks"
 
 export interface Interface {
-  readonly activate: (plugins: readonly Plugin[]) => Effect.Effect<void>
+  readonly activate: (plugins: readonly Versioned[]) => Effect.Effect<void>
   readonly list: () => Effect.Effect<Info[]>
 }
 
+export interface Versioned extends Plugin {
+  readonly version: string
+}
+
 export class Service extends Context.Service<Service, Interface>()("@opencode/v2/Plugin") {}
 
 const layer = Layer.effect(
@@ -32,11 +36,11 @@ const layer = Layer.effect(
   Effect.gen(function* () {
     const events = yield* EventV2.Service
     const scope = yield* Scope.make()
-    const active = new Map<typeof ID.Type, { readonly plugin: Plugin; readonly scope: Scope.Closeable }>()
+    const active = new Map<typeof ID.Type, { readonly plugin: Versioned; readonly scope: Scope.Closeable }>()
     const lock = Semaphore.makeUnsafe(1)
     let host: Parameters<Plugin["effect"]>[0]
 
-    const load = Effect.fnUntraced(function* (plugin: Plugin) {
+    const load = Effect.fnUntraced(function* (plugin: Versioned) {
       const child = yield* Scope.fork(scope)
       const inherit = yield* State.inherit()
       const loaded = yield* Effect.suspend(() => plugin.effect(host)).pipe(
@@ -55,7 +59,7 @@ const layer = Layer.effect(
       return undefined
     })
 
-    const activate = Effect.fn("Plugin.activate")(function* (plugins: readonly Plugin[]) {
+    const activate = Effect.fn("Plugin.activate")(function* (plugins: readonly Versioned[]) {
       const definitions = plugins.map((plugin) => ({ ...plugin, id: ID.make(plugin.id) }))
       const ids = new Set<typeof ID.Type>()
       for (const definition of definitions) {
@@ -65,6 +69,20 @@ const layer = Layer.effect(
 
       yield* lock.withPermit(
         Effect.gen(function* () {
+          const next = definitions.map((definition) => ({ id: definition.id, version: definition.version }))
+          const current = Array.from(active.values(), (entry) => ({
+            id: entry.plugin.id,
+            version: entry.plugin.version,
+          }))
+          if (
+            current.length === next.length &&
+            current.every((definition, index) => {
+              const candidate = next[index]
+              return definition.id === candidate?.id && definition.version === candidate.version
+            })
+          )
+            return
+
           yield* State.batch(
             Effect.gen(function* () {
               for (const definition of definitions) {

packages/core/src/plugin/models-dev.ts

@@ -26,7 +26,10 @@ export const ModelsDevPlugin = define({
     })
     yield* ctx.catalog.transform((catalog) => {
       for (const provider of loaded.data) {
-        catalog.provider.update(provider.info.id, (draft) => Object.assign(draft, provider.info))
+        catalog.provider.update(provider.info.id, (draft) => {
+          Object.assign(draft, provider.info)
+          draft.integrationID = provider.info.id
+        })
         for (const model of provider.models) {
           catalog.model.update(provider.info.id, model.id, (draft) => Object.assign(draft, model))
         }

packages/core/src/plugin/promise.ts

@@ -1,14 +1,24 @@
 export * as PluginPromise from "./promise"
 
-import { Plugin } from "@opencode-ai/plugin/v2/effect"
+import { define } from "@opencode-ai/plugin/v2/effect/plugin"
+import type { Context, Plugin } from "@opencode-ai/plugin/v2/plugin"
 import type { AnyTool } from "@opencode-ai/plugin/v2/tool"
-import { Effect, Scope, Stream } from "effect"
+import { Agent } from "@opencode-ai/schema/agent"
+import { Integration } from "@opencode-ai/schema/integration"
+import { Location } from "@opencode-ai/schema/location"
+import { Model } from "@opencode-ai/schema/model"
+import { Provider } from "@opencode-ai/schema/provider"
+import { AbsolutePath } from "@opencode-ai/schema/schema"
+import { Session } from "@opencode-ai/schema/session"
+import { SessionMessage } from "@opencode-ai/schema/session-message"
+import { Workspace } from "@opencode-ai/schema/workspace"
+import { DateTime, Effect, Scope, Stream } from "effect"
 import { Tool } from "../tool/tool"
 
 type HostRegistration = { readonly dispose: Effect.Effect<void> }
 type Registration = { readonly dispose: () => Promise<void> }
-type PromisePlugin = import("@opencode-ai/plugin/v2/plugin").Plugin
-type PromisePluginContext = import("@opencode-ai/plugin/v2/plugin").Context
+type PromiseEvent = ReturnType<Context["event"]["subscribe"]> extends AsyncIterable<infer Event> ? Event : never
+type JsonValue = null | boolean | number | string | Array<JsonValue> | { [key: string]: JsonValue }
 
 /**
  * Adapts a Promise plugin into an Effect plugin so the existing Effect-only
@@ -19,8 +29,8 @@ type PromisePluginContext = import("@opencode-ai/plugin/v2/plugin").Context
  * preserves boot-time batching, so Promise-plugin transforms still coalesce
  * into one reload per domain.
  */
-export function fromPromise(plugin: PromisePlugin) {
-  return Plugin.define({
+export function fromPromise(plugin: Plugin) {
+  return define({
     id: plugin.id,
     effect: (host) =>
       Effect.gen(function* () {
@@ -33,7 +43,7 @@ export function fromPromise(plugin: PromisePlugin) {
             dispose: () => Effect.runPromiseWith(context)(registration.dispose),
           }))
 
-        const run = <A, E>(effect: Effect.Effect<A, E>) => Effect.runPromiseWith(context)(effect)
+        const run = <A, E>(effect: Effect.Effect<A, E>) => Effect.runPromiseWith(context)(effect).then(wire)
 
         const transform =
           <Draft>(domain: {
@@ -46,7 +56,7 @@ export function fromPromise(plugin: PromisePlugin) {
               }),
             )
 
-        const context2: PromisePluginContext = {
+        const context2: Context = {
           options: host.options,
           agent: {
             list: (input) => run(host.agent.list(input)),
@@ -60,11 +70,12 @@ export function fromPromise(plugin: PromisePlugin) {
           catalog: {
             provider: {
               list: (input) => run(host.catalog.provider.list(input)),
-              get: (input) => run(host.catalog.provider.get(input)),
+              get: (input) => run(host.catalog.provider.get({ ...input, providerID: Provider.ID.make(input.providerID) })),
             },
             model: {
               list: (input) => run(host.catalog.model.list(input)),
-              default: (input) => run(host.catalog.model.default(input)),
+              default: (input) =>
+                run(host.catalog.model.default(input)).then((result) => ({ ...result, data: result.data ?? null })),
             },
             transform: transform(host.catalog),
             reload: () => run(host.catalog.reload()),
@@ -75,19 +86,48 @@ export function fromPromise(plugin: PromisePlugin) {
             reload: () => run(host.command.reload()),
           },
           event: {
-            subscribe: () => Stream.toAsyncIterable(host.event.subscribe()),
+            subscribe: () => Stream.toAsyncIterable(host.event.subscribe().pipe(Stream.map(wireEvent))),
           },
           integration: {
             list: (input) => run(host.integration.list(input)),
-            get: (input) => run(host.integration.get(input)),
+            get: (input) =>
+              run(host.integration.get({ ...input, integrationID: Integration.ID.make(input.integrationID) })).then(
+                (result) => ({ ...result, data: result.data ?? null }),
+              ),
             connect: {
-              key: (input) => run(host.integration.connect.key(input)),
-              oauth: (input) => run(host.integration.connect.oauth(input)),
+              key: (input) =>
+                run(host.integration.connect.key({ ...input, integrationID: Integration.ID.make(input.integrationID) })),
+              oauth: (input) =>
+                run(
+                  host.integration.connect.oauth({
+                    ...input,
+                    integrationID: Integration.ID.make(input.integrationID),
+                    methodID: Integration.MethodID.make(input.methodID),
+                  }),
+                ),
             },
             attempt: {
-              status: (input) => run(host.integration.attempt.status(input)),
-              complete: (input) => run(host.integration.attempt.complete(input)),
-              cancel: (input) => run(host.integration.attempt.cancel(input)),
+              status: (input) =>
+                run(
+                  host.integration.attempt.status({
+                    ...input,
+                    attemptID: Integration.AttemptID.make(input.attemptID),
+                  }),
+                ),
+              complete: (input) =>
+                run(
+                  host.integration.attempt.complete({
+                    ...input,
+                    attemptID: Integration.AttemptID.make(input.attemptID),
+                  }),
+                ),
+              cancel: (input) =>
+                run(
+                  host.integration.attempt.cancel({
+                    ...input,
+                    attemptID: Integration.AttemptID.make(input.attemptID),
+                  }),
+                ),
             },
             transform: transform(host.integration),
             reload: () => run(host.integration.reload()),
@@ -122,11 +162,53 @@ export function fromPromise(plugin: PromisePlugin) {
               register(host.tool.hook(name, (event) => Effect.promise(() => Promise.resolve(callback(event))))),
           },
           session: {
-            create: (input) => run(host.session.create(input)),
-            get: (input) => run(host.session.get(input)),
-            prompt: (input) => run(host.session.prompt(input)),
-            command: (input) => run(host.session.command(input)),
-            interrupt: (input) => run(host.session.interrupt(input)),
+            create: (input) =>
+              run(
+                host.session.create(
+                  input === undefined
+                    ? undefined
+                    : {
+                        id: input.id == null ? undefined : Session.ID.make(input.id),
+                        agent: input.agent == null ? undefined : Agent.ID.make(input.agent),
+                        model: input.model == null ? undefined : model(input.model),
+                        location:
+                          input.location == null
+                            ? undefined
+                            : Location.Ref.make({
+                                directory: AbsolutePath.make(input.location.directory),
+                                workspaceID:
+                                  input.location.workspaceID === undefined
+                                    ? undefined
+                                    : Workspace.ID.make(input.location.workspaceID),
+                              }),
+                      },
+                ),
+              ),
+            get: (input) => run(host.session.get({ sessionID: Session.ID.make(input.sessionID) })),
+            prompt: (input) =>
+              run(
+                host.session.prompt({
+                  ...input,
+                  sessionID: Session.ID.make(input.sessionID),
+                  id: input.id == null ? undefined : SessionMessage.ID.make(input.id),
+                  delivery: input.delivery ?? undefined,
+                  resume: input.resume ?? undefined,
+                }),
+              ),
+            command: (input) =>
+              run(
+                host.session.command({
+                  ...input,
+                  sessionID: Session.ID.make(input.sessionID),
+                  id: input.id == null ? undefined : SessionMessage.ID.make(input.id),
+                  agent: input.agent == null ? undefined : Agent.ID.make(input.agent),
+                  model: input.model == null ? undefined : model(input.model),
+                  arguments: input.arguments ?? undefined,
+                  delivery: input.delivery ?? undefined,
+                  resume: input.resume ?? undefined,
+                }),
+              ),
+            interrupt: (input) => run(host.session.interrupt({ sessionID: Session.ID.make(input.sessionID) })),
           },
         }
 
@@ -137,6 +219,39 @@ export function fromPromise(plugin: PromisePlugin) {
   })
 }
 
+function model(input: { readonly id: string; readonly providerID: string; readonly variant?: string }) {
+  return Model.Ref.make({
+    id: Model.ID.make(input.id),
+    providerID: Provider.ID.make(input.providerID),
+    variant: input.variant === undefined ? undefined : Model.VariantID.make(input.variant),
+  })
+}
+
+type Wire<Value> = unknown extends Value
+  ? JsonValue
+  : Value extends string | number | boolean | bigint | symbol | null | undefined
+    ? Value
+    : Value extends DateTime.DateTime
+      ? number
+      : Value extends ReadonlyArray<infer Item>
+        ? Array<Wire<Item>>
+        : Value extends object
+          ? { -readonly [Key in keyof Value]: Wire<Value[Key]> }
+          : Value
+
+function wire<Value>(value: Value): Wire<Value>
+function wire(value: unknown): unknown {
+  if (DateTime.isDateTime(value)) return DateTime.toEpochMillis(value)
+  if (Array.isArray(value)) return value.map(wire)
+  if (typeof value !== "object" || value === null) return value
+  return Object.fromEntries(Object.entries(value).map(([key, item]) => [key, wire(item)]))
+}
+
+function wireEvent(value: unknown): PromiseEvent
+function wireEvent(value: unknown): unknown {
+  return wire(value)
+}
+
 function fromPromiseTool(tool: AnyTool) {
   if ("jsonSchema" in tool)
     return Tool.make({