refactor(app): split server management controllers

.opencode/plugins/tui/discovery-smoke.ts

@@ -2,12 +2,15 @@ import type { Context } from "../../../packages/plugin/src/tui/context"
 
 export default {
   id: "test.tui-discovery-smoke",
-  setup(_context: Context) {
-    // context.ui.toast.show({
-    //   title: "TUI plugin discovery works",
-    //   message: "Loaded .opencode/plugins/tui/discovery-smoke.ts",
-    //   variant: "success",
-    //   duration: 30_000,
-    // })
+  setup(context: Context) {
+    const timer = setTimeout(() => {
+      context.ui.toast.show({
+        title: "TUI plugin discovery works",
+        message: "Loaded .opencode/plugins/tui/discovery-smoke.ts",
+        variant: "success",
+        duration: 30_000,
+      })
+    }, 1_000)
+    return () => clearTimeout(timer)
   },
 }

bun.lock

@@ -600,7 +600,6 @@
         "zod": "catalog:",
       },
       "devDependencies": {
-        "@opencode-ai/theme": "workspace:*",
         "@opentui/core": "catalog:",
         "@opentui/keymap": "catalog:",
         "@opentui/solid": "catalog:",
@@ -612,14 +611,12 @@
         "typescript": "catalog:",
       },
       "peerDependencies": {
-        "@opencode-ai/theme": "workspace:*",
         "@opentui/core": ">=0.4.5",
         "@opentui/keymap": ">=0.4.5",
         "@opentui/solid": ">=0.4.5",
         "solid-js": ">=1.9.0",
       },
       "optionalPeers": [
-        "@opencode-ai/theme",
         "@opentui/core",
         "@opentui/keymap",
         "@opentui/solid",

docs/design/v1-v2-database-migration.md

@@ -1,118 +0,0 @@
-# V1 to V2 Database Migration
-
-## Approach
-
-- Use the `dev` branch database schema and migration registry as the V1 baseline.
-- Remove migrations that exist only on the V2 branch.
-- Generate one canonical migration from the `dev` schema to the final V2 schema.
-- Add explicit data operations to that migration where generated DDL is insufficient.
-- Test the migration against a populated database at the exact `dev` schema.
-
-## Preserve
-
-The canonical V1 data remains in its existing tables. In particular, preserve `session`, `message`, and `part` rows.
-
-Preserve `workspace` rows and existing `session.workspace_id` values unchanged. The migration must not clear or rebuild
-workspace relationships.
-
-Keep the `todo` table and its data unchanged. V2 does not currently migrate todos into another representation, and the
-generated migration must not drop the table.
-
-## Truncate
-
-Truncate these pre-launch V2 tables before applying schema changes:
-
-- `event`
-- `event_sequence`
-- `session_message`
-
-These rows are not canonical V1 data. Truncating `event` before adding the required `event.created` column means the
-column needs neither a backfill nor a default. After truncation, rebuild `session_message` from canonical V1 `message`
-and `part` rows rather than retaining its pre-launch V2 contents.
-
-## Message Backfill
-
-Backfill canonical V1 history from `message` and `part` into `session_message`. This is the main data transformation in
-the migration. Preserving the V1 tables alone keeps the data safe but does not make existing history visible through the
-V2 session APIs, which read `session_message`.
-
-Reuse each V1 `message.id` as the corresponding `session_message.id`. Stable IDs keep the migration deterministic and
-avoid rewriting other persisted state that may refer to a message.
-
-Within each session, order V1 messages by `time_created` and then `id`, matching the existing V1 message index. Assign
-contiguous `session_message.seq` values starting at `0`.
-
-Map ordinary V1 messages one-to-one by role. Each ordinary V1 user message becomes one V2 `user` row, and each ordinary
-V1 assistant message becomes one V2 `assistant` row. Fold the source message's ordered V1 parts into that row's V2
-payload.
-
-Handle semantic marker parts before applying the ordinary mapping. In particular, a V1 user message containing a
-`compaction` part and its paired assistant summary represent one compaction operation, not two ordinary messages. Special
-part mappings must be decided explicitly before implementing the backfill.
-
-V1 synthetic content is represented by user text parts with `synthetic: true`, not by a separate message role. A V1 user
-message whose visible text parts are all synthetic should become a V2 `synthetic` message. If a V1 user message mixes
-ordinary and synthetic content, preserve the ordinary content in the V2 `user` row and emit the synthetic content as an
-adjacent V2 `synthetic` row. Ignore text parts marked `ignored`, matching V1 model-history behavior.
-
-Use the V1 compaction user message ID as the ID of the collapsed V2 compaction message. This matches V2's use of the
-admitted compaction input ID and preserves references to the initiating message.
-
-For a completed compaction, create one V2 `compaction` row with `status: "completed"`. Set `reason` from the V1
-compaction part's `auto` flag, join the paired summary assistant's nonempty text parts with blank lines for `summary`, and
-serialize the retained V1 tail beginning at `tail_start_id` for `recent`. Use an empty `recent` value when no tail was
-retained, and use the compaction user message creation time. Do not emit the paired summary assistant as a separate V2
-assistant row.
-
-After rebuilding `session_message`, seed `event_sequence` with one row per migrated session. Set its watermark to that
-session's maximum backfilled `session_message.seq`. This prevents new V2 events from reusing sequence numbers or sorting
-before migrated history. The `event` table remains empty.
-
-## Drop
-
-Drop these pre-launch V2 tables without preserving or transforming their rows:
-
-- `session_input`
-- `session_context_epoch`
-
-Do not transfer `session_input` rows into `session_pending`.
-
-## Create Empty
-
-Let the generated migration create these tables empty:
-
-- `instruction_blob`
-- `instruction_entry`
-- `instruction_state`
-- `session_pending`
-- `kv`
-
-V1 has no canonical data to backfill into these tables. V2 initializes their state as it runs.
-
-## Fork Storage
-
-V1 has no fork-boundary state to backfill. New V2 forks use a required message boundary and persist it in
-`session.fork_boundary`. The durable fork event contains no parent sequence. Its resolved boundary is one of:
-
-- `before`: copy messages before the identified message.
-- `through`: copy messages through the identified message.
-
-Forking an empty session is not supported. `session.fork_seq` and `session.fork_message_id` are not part of the final V2
-schema.
-
-New nullable session columns, including `fork_session_id`, `fork_boundary`, and `time_suspended`, require no explicit
-backfill. Existing rows naturally receive `NULL` when the generated migration adds the columns.
-
-## Verification
-
-The canonical migration test should seed representative V1 sessions, messages, parts, todos, projects, accounts,
-credentials, permissions, shares, and workspaces. After migration, it should verify:
-
-- Preserved rows and encoded values remain unchanged.
-- Todo rows remain available in the unchanged `todo` table.
-- `event` is empty, and stale pre-launch rows are absent from the rebuilt projections.
-- Backfilled `session_message` rows represent the canonical V1 `message` and `part` history.
-- Each migrated session's `event_sequence` watermark matches its maximum backfilled message sequence.
-- Dropped tables no longer exist.
-- New tables exist and are empty.
-- The final schema has no ungenerated changes.

packages/ai/AGENTS.md

@@ -46,7 +46,7 @@ const response = yield * LLMClient.generate(request)
 
 `LLM.request(...)` builds an `LLMRequest`. `LLMClient.generate(...)` reads the executable route carried by `request.model.route`, builds the provider-native body, asks the route's transport for a real `HttpClientRequest.HttpClientRequest`, sends it through `RequestExecutor.Service`, parses the provider stream into common `LLMEvent`s, and finally returns an `LLMResponse`.
 
-Use `LLMClient.stream(request)` when callers want incremental `LLMEvent`s. Use `LLMClient.generate(request)` when callers want those same events collected into an `LLMResponse`.
+Use `LLMClient.stream(request)` when callers want incremental `LLMEvent`s. Use `LLMClient.generate(request)` when callers want those same events collected into an `LLMResponse`. Use `LLMClient.prepare<Body>(request)` to compile a request through the route pipeline without sending it — the optional `Body` type argument narrows `.body` to the route's native shape (e.g. `prepare<OpenAIChatBody>(...)` returns a `PreparedRequestOf<OpenAIChatBody>`). The runtime body is identical; the generic is a type-level assertion.
 
 Filter or narrow `LLMEvent` streams with `LLMEvent.is.*` (camelCase guards, e.g. `events.filter(LLMEvent.is.toolCall)`). The kebab-case `LLMEvent.guards["tool-call"]` form also works but prefer `is.*` in new code.
 
@@ -138,13 +138,13 @@ packages/ai/src/
     ids.ts                  branded IDs, literal types, ProviderMetadata
     options.ts              Generation/Provider/Http options, Limits, Model, cache policy
     messages.ts             content parts, Message, ToolDefinition, LLMRequest
-    events.ts               Usage, individual events, LLMEvent, LLMResponse
+    events.ts               Usage, individual events, LLMEvent, PreparedRequest, LLMResponse
     errors.ts               error reasons, LLMError, ToolFailure
     index.ts                barrel
   llm.ts                    request constructors and convenience helpers
   route/
     index.ts                @opencode-ai/ai/route advanced barrel
-    client.ts               Route.make + LLMClient.stream/generate
+    client.ts               Route.make + LLMClient.prepare/stream/generate
     executor.ts             RequestExecutor service + transport error mapping
     protocol.ts             Protocol type + Protocol.make
     endpoint.ts             Endpoint type + Endpoint.path

packages/ai/README.md

@@ -196,6 +196,7 @@ The hosted result is represented as a provider-executed tool call and tool resul
 - **`LLM.generate` / `LLM.stream`** — re-exported from `LLMClient` for one-import use.
 - **`Message.user(...)` / `Message.assistant(...)` / `Message.tool(...)`** — message constructors from the canonical schema model.
 - **`Model.make(...)` / `ToolCallPart.make(...)` / `ToolResultPart.make(...)` / `ToolDefinition.make(...)`** — model and tool-related constructors from the canonical schema model.
+- **`LLMClient.prepare(request)`** — compile a request through protocol body construction, validation, and HTTP preparation without sending. Useful for inspection and testing.
 - **`LLMEvent.is.*`** — typed guards (`is.textDelta`, `is.toolCall`, `is.finish`, …) for filtering streams.
 - **`Image.generate({...})`** — generate images through a provider-neutral image request and response model.
 - **`ImageClient`** — Effect service and layer for image execution, parallel to `LLMClient`.

packages/ai/example/call-sites.md

@@ -568,7 +568,7 @@ App boundary = explicit durable-config -> typed-provider call
       calling `.model(...)`.
 - [x] Remove request-shaping defaults from `Model`; selected models now carry only
       id, provider, and configured route while defaults live on routes or requests.
-- [x] Rework `LLMClient.stream` / `generate` to read
+- [x] Rework `LLMClient.prepare` / `stream` / `generate` to read
       `request.model.route` directly instead of calling `registeredRoute(...)`.
 - [x] Remove `Route.make(...)` global registration from the normal execution
       path; keep route ids only as diagnostics/provider API labels.

packages/ai/example/tutorial.ts

@@ -50,6 +50,18 @@ const request = LLM.request({
   },
 })
 
+// `http` is intentionally not needed for normal calls. This shows the shape for
+// newly released provider fields before they deserve a typed provider option.
+const rawOverlayExample = LLM.request({
+  model,
+  prompt: "Show the final HTTP overlay shape.",
+  http: {
+    body: { metadata: { example: "tutorial" } },
+    headers: { "x-opencode-tutorial": "1" },
+    query: { debug: "1" },
+  },
+})
+
 // 3. `generate` sends the request and collects the event stream into one
 // response object. `response.text` is the collected text output.
 const generateOnce = Effect.gen(function* () {
@@ -210,15 +222,33 @@ const FakeEcho = {
   }),
 }
 
+// `LLMClient.prepare` is the lower-level inspection hook: it compiles through
+// body conversion, validation, endpoint, auth, and HTTP construction without
+// sending anything over the network.
+const inspectFakeProvider = Effect.gen(function* () {
+  const prepared = yield* LLMClient.prepare(
+    LLM.request({
+      model: FakeEcho.configure().model("tiny-echo"),
+      prompt: "Show me the provider pipeline.",
+    }),
+  )
+
+  console.log("\n== fake provider prepare ==")
+  console.log("route:", prepared.route)
+  console.log("body:", Formatter.formatJson(prepared.body, { space: 2 }))
+})
+
 // Provide the LLM runtime and the HTTP request executor once. Keep one path
-// enabled at a time so the tutorial can demonstrate generate, stream, or
-// tool-loop behavior without spending tokens on every example.
+// enabled at a time so the tutorial can demonstrate generate, prepare, stream,
+// or tool-loop behavior without spending tokens on every example.
 const requestExecutorLayer = RequestExecutor.fetchLayer
 const llmDeps = Layer.mergeAll(requestExecutorLayer, WebSocketExecutor.layer)
 const llmClientLayer = LLMClient.layer.pipe(Layer.provide(llmDeps))
 
 const program = Effect.gen(function* () {
   // yield* generateOnce
+  // yield* inspectFakeProvider
+  // yield* LLMClient.prepare(rawOverlayExample).pipe(Effect.andThen((prepared) => Effect.sync(() => console.log(prepared.body))))
   // yield* streamText
   // yield* generateStructuredObject
   // yield* generateDynamicObject.pipe(Effect.andThen((response) => Effect.sync(() => console.log(response.object))))

packages/ai/src/llm.ts

@@ -9,28 +9,25 @@ import {
   LLMRequest,
   LLMResponse,
   Message,
-  Model,
   SystemPart,
   ToolChoice,
   ToolDefinition,
   type ContentPart,
-  type ModelProviderOptions,
 } from "./schema"
 import { make as makeTool, toDefinitions, type ToolSchema } from "./tool"
 
 /** Input accepted by `LLM.request`, normalized into the canonical `LLMRequest` class. */
-export type RequestInput<SelectedModel extends Model = Model> = Omit<
+export type RequestInput = Omit<
   ConstructorParameters<typeof LLMRequest>[0],
-  "model" | "system" | "messages" | "tools" | "toolChoice" | "generation" | "http" | "providerOptions"
+  "system" | "messages" | "tools" | "toolChoice" | "generation" | "http" | "providerOptions"
 > & {
-  readonly model: SelectedModel
   readonly system?: string | SystemPart | ReadonlyArray<SystemPart>
   readonly prompt?: string | ContentPart | ReadonlyArray<ContentPart>
   readonly messages?: ReadonlyArray<Message | Message.Input>
   readonly tools?: ReadonlyArray<ToolDefinition.Input>
   readonly toolChoice?: ToolChoice.Input
   readonly generation?: GenerationOptions.Input
-  readonly providerOptions?: NoInfer<ModelProviderOptions<SelectedModel>>
+  readonly providerOptions?: ConstructorParameters<typeof LLMRequest>[0]["providerOptions"]
   readonly http?: HttpOptions.Input
 }
 
@@ -38,7 +35,7 @@ export const generate = LLMClient.generate
 
 export const stream = LLMClient.stream
 
-export const request = <const SelectedModel extends Model>(input: RequestInput<SelectedModel>) => {
+export const request = (input: RequestInput) => {
   const {
     system: requestSystem,
     prompt,
@@ -66,7 +63,7 @@ const GENERATE_OBJECT_TOOL_NAME = "generate_object"
 
 const GENERATE_OBJECT_TOOL_DESCRIPTION = "Return the structured result by calling this tool."
 
-type GenerateObjectBase<SelectedModel extends Model = Model> = Omit<RequestInput<SelectedModel>, "tools" | "toolChoice">
+type GenerateObjectBase = Omit<RequestInput, "tools" | "toolChoice">
 
 export class GenerateObjectResponse<T> {
   constructor(
@@ -83,13 +80,11 @@ export class GenerateObjectResponse<T> {
   }
 }
 
-export interface GenerateObjectOptions<S extends ToolSchema<any>, SelectedModel extends Model = Model>
-  extends GenerateObjectBase<SelectedModel> {
+export interface GenerateObjectOptions<S extends ToolSchema<any>> extends GenerateObjectBase {
   readonly schema: S
 }
 
-export interface GenerateObjectDynamicOptions<SelectedModel extends Model = Model>
-  extends GenerateObjectBase<SelectedModel> {
+export interface GenerateObjectDynamicOptions extends GenerateObjectBase {
   /** Raw JSON Schema object describing the expected output shape. */
   readonly jsonSchema: JsonSchema.JsonSchema
 }
@@ -142,11 +137,11 @@ const runGenerateObject = Effect.fn("LLM.generateObject")(function* (
  * 2. `jsonSchema: JsonSchema.JsonSchema` — `.object` is `unknown`. Use when
  *    the schema is only available at runtime (MCP, plugin manifests). Caller validates.
  */
-export function generateObject<const SelectedModel extends Model, S extends ToolSchema<any>>(
-  options: GenerateObjectOptions<S, SelectedModel>,
+export function generateObject<S extends ToolSchema<any>>(
+  options: GenerateObjectOptions<S>,
 ): Effect.Effect<GenerateObjectResponse<Schema.Schema.Type<S>>, LLMError>
-export function generateObject<const SelectedModel extends Model>(
-  options: GenerateObjectDynamicOptions<SelectedModel>,
+export function generateObject(
+  options: GenerateObjectDynamicOptions,
 ): Effect.Effect<GenerateObjectResponse<unknown>, LLMError>
 export function generateObject(options: GenerateObjectOptions<ToolSchema<any>> | GenerateObjectDynamicOptions) {
   if ("schema" in options) {

packages/ai/src/provider-package.ts

@@ -1,4 +1,4 @@
-import type { Model, ProviderOptions } from "./schema"
+import type { Model } from "./schema"
 
 export interface Settings extends Readonly<Record<string, unknown>> {
   readonly headers?: Readonly<Record<string, string>>
@@ -9,11 +9,8 @@ export interface Settings extends Readonly<Record<string, unknown>> {
   }
 }
 
-export interface Definition<
-  ProviderSettings extends Settings = Settings,
-  Options extends ProviderOptions = ProviderOptions,
-> {
-  readonly model: (modelID: string, settings: ProviderSettings) => Model<Options>
+export interface Definition<ProviderSettings extends Settings = Settings> {
+  readonly model: (modelID: string, settings: ProviderSettings) => Model
 }
 
 export * as ProviderPackage from "./provider-package"

packages/ai/src/providers/anthropic-compatible.ts

@@ -47,7 +47,7 @@ export const configure = (input: Config) => {
   })
   return {
     id: ProviderID.make(provider),
-    model: (modelID: string | ModelID) => route.model<AnthropicMessages.ProviderOptionsInput>({ id: modelID }),
+    model: (modelID: string | ModelID) => route.model({ id: modelID }),
     configure,
   }
 }
@@ -57,10 +57,7 @@ export const provider = {
   configure,
 }
 
-export const model: ProviderPackage.Definition<Settings, AnthropicMessages.ProviderOptionsInput>["model"] = (
-  modelID,
-  settings,
-) => {
+export const model: ProviderPackage.Definition<Settings>["model"] = (modelID, settings) => {
   if (settings.apiKey !== undefined && settings.authToken !== undefined)
     throw new Error("Anthropic-compatible apiKey cannot be combined with authToken")
   return configure({

packages/ai/src/providers/anthropic.ts

@@ -52,10 +52,7 @@ export const configure = (input: Config = {}) => {
 }
 
 export const provider = configure()
-export const model: ProviderPackage.Definition<Settings, AnthropicMessages.ProviderOptionsInput>["model"] = (
-  modelID,
-  settings,
-) => {
+export const model: ProviderPackage.Definition<Settings>["model"] = (modelID, settings) => {
   if (settings.apiKey !== undefined && settings.authToken !== undefined)
     throw new Error("Anthropic apiKey cannot be combined with authToken")
   return configure({

packages/ai/src/providers/azure.ts

@@ -99,14 +99,10 @@ export const configure = (input: Config) => {
   const modelDefaults = defaults(input)
 
   const responses = (modelID: string | ModelID) =>
-    configuredResponsesRoute
-      .with(withOpenAIOptions(modelID, modelDefaults))
-      .model<OpenAIProviderOptionsInput>({ id: modelID })
+    configuredResponsesRoute.with(withOpenAIOptions(modelID, modelDefaults)).model({ id: modelID })
 
   const chat = (modelID: string | ModelID) =>
-    configuredChatRoute
-      .with(withOpenAIOptions(modelID, modelDefaults))
-      .model<OpenAIProviderOptionsInput>({ id: modelID })
+    configuredChatRoute.with(withOpenAIOptions(modelID, modelDefaults)).model({ id: modelID })
 
   return {
     id,
@@ -137,12 +133,8 @@ const config = (settings: Settings): Config => {
   throw new Error("Azure requires resourceName or baseURL")
 }
 
-export const responsesModel: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (
-  modelID,
-  settings,
-) => configure(config(settings)).responses(modelID)
-export const chatModel: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (
-  modelID,
-  settings,
-) => configure(config(settings)).chat(modelID)
+export const responsesModel: ProviderPackage.Definition<Settings>["model"] = (modelID, settings) =>
+  configure(config(settings)).responses(modelID)
+export const chatModel: ProviderPackage.Definition<Settings>["model"] = (modelID, settings) =>
+  configure(config(settings)).chat(modelID)
 export const model = responsesModel

packages/ai/src/providers/cloudflare.ts

@@ -4,7 +4,6 @@ import { Auth } from "../route/auth"
 import { AuthOptions, type AtLeastOne, type ProviderAuthOption } from "../route/auth-options"
 import type { RouteDefaultsInput } from "../route/client"
 import { ProviderID, type ModelID } from "../schema"
-import type { OpenAIProviderOptionsInput } from "./openai-options"
 
 export const aiGatewayID = ProviderID.make("cloudflare-ai-gateway")
 export const workersAIID = ProviderID.make("cloudflare-workers-ai")
@@ -21,11 +20,10 @@ type GatewayURL = AtLeastOne<{
 }
 
 export type AIGatewayOptions = GatewayURL &
-  Omit<RouteDefaultsInput, "providerOptions"> &
+  RouteDefaultsInput &
   ProviderAuthOption<"optional"> & {
     /** Cloudflare AI Gateway authentication token. Sent as `cf-aig-authorization`. */
     readonly gatewayApiKey?: CloudflareSecret
-    readonly providerOptions?: OpenAIProviderOptionsInput
   }
 
 type WorkersAIURL = AtLeastOne<{
@@ -33,11 +31,7 @@ type WorkersAIURL = AtLeastOne<{
   readonly baseURL: string
 }>
 
-export type WorkersAIOptions = WorkersAIURL &
-  Omit<RouteDefaultsInput, "providerOptions"> &
-  ProviderAuthOption<"optional"> & {
-    readonly providerOptions?: OpenAIProviderOptionsInput
-  }
+export type WorkersAIOptions = WorkersAIURL & RouteDefaultsInput & ProviderAuthOption<"optional">
 
 export const aiGatewayBaseURL = (input: GatewayURL) => {
   if (input.baseURL) return input.baseURL
@@ -104,7 +98,7 @@ const configureAIGateway = (options: AIGatewayOptions) => {
   })
   return {
     id: aiGatewayID,
-    model: (modelID: string | ModelID) => route.model<OpenAIProviderOptionsInput>({ id: modelID }),
+    model: (modelID: string | ModelID) => route.model({ id: modelID }),
     configure: configureAIGateway,
   }
 }
@@ -117,7 +111,7 @@ const configureWorkersAI = (options: WorkersAIOptions) => {
   })
   return {
     id: workersAIID,
-    model: (modelID: string | ModelID) => route.model<OpenAIProviderOptionsInput>({ id: modelID }),
+    model: (modelID: string | ModelID) => route.model({ id: modelID }),
     configure: configureWorkersAI,
   }
 }

packages/ai/src/providers/github-copilot.ts

@@ -50,11 +50,9 @@ export const configure = (options: ModelOptions) => {
   const responsesRoute = configuredResponsesRoute(options)
   const chatRoute = configuredChatRoute(options)
   const responses = (modelID: string | ModelID) =>
-    responsesRoute
-      .with(withOpenAIOptions(modelID, defaults(options)))
-      .model<OpenAIProviderOptionsInput>({ id: modelID })
+    responsesRoute.with(withOpenAIOptions(modelID, defaults(options))).model({ id: modelID })
   const chat = (modelID: string | ModelID) =>
-    chatRoute.with(withOpenAIOptions(modelID, defaults(options))).model<OpenAIProviderOptionsInput>({ id: modelID })
+    chatRoute.with(withOpenAIOptions(modelID, defaults(options))).model({ id: modelID })
   return {
     id,
     model: (modelID: string | ModelID) =>

packages/ai/src/providers/google-vertex-chat.ts

@@ -1,9 +1,8 @@
 import type { ProviderPackage } from "../provider-package"
 import { OpenAICompatibleChat } from "../protocols/openai-compatible-chat"
 import type { RouteDefaultsInput } from "../route/client"
-import { ProviderID, type ModelID } from "../schema"
+import { ProviderID, type ModelID, type ProviderOptions } from "../schema"
 import { GoogleVertexShared } from "./google-vertex-shared"
-import type { OpenAIProviderOptionsInput } from "./openai-options"
 
 export const id = ProviderID.make("google-vertex")
 
@@ -12,7 +11,6 @@ export type Config = RouteDefaultsInput &
     readonly baseURL?: string
     readonly location?: string
     readonly project?: string
-    readonly providerOptions?: OpenAIProviderOptionsInput
   }
 
 export interface Settings extends ProviderPackage.Settings {
@@ -21,7 +19,7 @@ export interface Settings extends ProviderPackage.Settings {
   readonly baseURL?: string
   readonly location?: string
   readonly project?: string
-  readonly providerOptions?: OpenAIProviderOptionsInput
+  readonly providerOptions?: ProviderOptions
 }
 
 const route = OpenAICompatibleChat.route.with({
@@ -58,7 +56,7 @@ export const configure = (input: Config = {}) => {
   const route = configuredRoute(input)
   return {
     id,
-    model: (modelID: string | ModelID) => route.model<OpenAIProviderOptionsInput>({ id: modelID }),
+    model: (modelID: string | ModelID) => route.model({ id: modelID }),
     configure,
   }
 }
@@ -68,7 +66,7 @@ export const provider = {
   configure,
 }
 
-export const model: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (modelID, settings) => {
+export const model: ProviderPackage.Definition<Settings>["model"] = (modelID, settings) => {
   if (settings.apiKey !== undefined) throw new Error("Google Vertex Chat does not support API keys")
   return configure({
     accessToken: settings.accessToken,

packages/ai/src/providers/google-vertex-messages.ts

@@ -91,7 +91,7 @@ export const configure = (input: Config = {}) => {
   const route = configuredRoute(input)
   return {
     id,
-    model: (modelID: string | ModelID) => route.model<AnthropicMessages.ProviderOptionsInput>({ id: modelID }),
+    model: (modelID: string | ModelID) => route.model({ id: modelID }),
     configure,
   }
 }
@@ -101,10 +101,7 @@ export const provider = {
   configure,
 }
 
-export const model: ProviderPackage.Definition<Settings, AnthropicMessages.ProviderOptionsInput>["model"] = (
-  modelID,
-  settings,
-) => {
+export const model: ProviderPackage.Definition<Settings>["model"] = (modelID, settings) => {
   if (settings.apiKey !== undefined) throw new Error("Google Vertex Messages does not support API keys")
   return configure({
     accessToken: settings.accessToken,

packages/ai/src/providers/google-vertex-responses.ts

@@ -1,9 +1,8 @@
 import type { ProviderPackage } from "../provider-package"
 import { OpenAICompatibleResponses } from "../protocols/openai-compatible-responses"
 import type { RouteDefaultsInput } from "../route/client"
-import { ProviderID, type ModelID } from "../schema"
+import { ProviderID, type ModelID, type ProviderOptions } from "../schema"
 import { GoogleVertexShared } from "./google-vertex-shared"
-import type { OpenResponsesProviderOptionsInput } from "./open-responses-options"
 
 export const id = ProviderID.make("google-vertex")
 
@@ -12,7 +11,6 @@ export type Config = RouteDefaultsInput &
     readonly baseURL?: string
     readonly location?: string
     readonly project?: string
-    readonly providerOptions?: OpenResponsesProviderOptionsInput
   }
 
 export interface Settings extends ProviderPackage.Settings {
@@ -21,7 +19,7 @@ export interface Settings extends ProviderPackage.Settings {
   readonly baseURL?: string
   readonly location?: string
   readonly project?: string
-  readonly providerOptions?: OpenResponsesProviderOptionsInput
+  readonly providerOptions?: ProviderOptions
 }
 
 const route = OpenAICompatibleResponses.route.with({
@@ -60,7 +58,7 @@ export const configure = (input: Config = {}) => {
   const route = configuredRoute(input)
   return {
     id,
-    model: (modelID: string | ModelID) => route.model<OpenResponsesProviderOptionsInput>({ id: modelID }),
+    model: (modelID: string | ModelID) => route.model({ id: modelID }),
     configure,
   }
 }
@@ -70,10 +68,7 @@ export const provider = {
   configure,
 }
 
-export const model: ProviderPackage.Definition<Settings, OpenResponsesProviderOptionsInput>["model"] = (
-  modelID,
-  settings,
-) => {
+export const model: ProviderPackage.Definition<Settings>["model"] = (modelID, settings) => {
   if (settings.apiKey !== undefined) throw new Error("Google Vertex Responses does not support API keys")
   return configure({
     accessToken: settings.accessToken,

packages/ai/src/providers/google-vertex.ts

@@ -77,8 +77,7 @@ const configuredRoute = (input: Config, modelID: string | ModelID) => {
 export const configure = (input: Config = {}) => {
   return {
     id,
-    model: (modelID: string | ModelID) =>
-      configuredRoute(input, modelID).model<Gemini.ProviderOptionsInput>({ id: modelID }),
+    model: (modelID: string | ModelID) => configuredRoute(input, modelID).model({ id: modelID }),
     configure,
   }
 }
@@ -87,10 +86,7 @@ export const provider = {
   id,
   configure,
 }
-export const model: ProviderPackage.Definition<Settings, Gemini.ProviderOptionsInput>["model"] = (
-  modelID,
-  settings,
-) => {
+export const model: ProviderPackage.Definition<Settings>["model"] = (modelID, settings) => {
   if (settings.apiKey !== undefined && settings.accessToken !== undefined)
     throw new Error("Google Vertex apiKey cannot be combined with accessToken or auth")
   return configure({

packages/ai/src/providers/google.ts

@@ -50,14 +50,14 @@ export const configure = (input: Config = {}) => {
     })
   return {
     id,
-    model: (modelID: string | ModelID) => route.model<Gemini.ProviderOptionsInput>({ id: modelID }),
+    model: (modelID: string | ModelID) => route.model({ id: modelID }),
     image,
     configure,
   }
 }
 
 export const provider = configure()
-export const model: ProviderPackage.Definition<Settings, Gemini.ProviderOptionsInput>["model"] = (modelID, settings) =>
+export const model: ProviderPackage.Definition<Settings>["model"] = (modelID, settings) =>
   configure({
     apiKey: settings.apiKey,
     baseURL: settings.baseURL,

packages/ai/src/providers/openai-compatible-responses.ts

@@ -36,7 +36,7 @@ export const configure = (input: Config) => {
   })
   return {
     id: ProviderID.make(provider),
-    model: (modelID: string | ModelID) => route.model<OpenResponsesProviderOptionsInput>({ id: modelID }),
+    model: (modelID: string | ModelID) => route.model({ id: modelID }),
     configure,
   }
 }
@@ -46,10 +46,7 @@ export const provider = {
   configure,
 }
 
-export const model: ProviderPackage.Definition<Settings, OpenResponsesProviderOptionsInput>["model"] = (
-  modelID,
-  settings,
-) =>
+export const model: ProviderPackage.Definition<Settings>["model"] = (modelID, settings) =>
   configure({
     apiKey: settings.apiKey,
     baseURL: settings.baseURL,

packages/ai/src/providers/openai-compatible.ts

@@ -4,15 +4,13 @@ import type { RouteDefaultsInput } from "../route/client"
 import { AuthOptions, type ProviderAuthOption } from "../route/auth-options"
 import type { ProviderPackage } from "../provider-package"
 import { profiles, type OpenAICompatibleProfile } from "./openai-compatible-profile"
-import type { OpenAIProviderOptionsInput } from "./openai-options"
 
 export const id = ProviderID.make("openai-compatible")
 
-type GenericModelOptions = Omit<RouteDefaultsInput, "providerOptions"> &
+type GenericModelOptions = RouteDefaultsInput &
   ProviderAuthOption<"optional"> & {
     readonly provider?: string
     readonly baseURL: string
-    readonly providerOptions?: OpenAIProviderOptionsInput
   }
 
 export interface Settings extends ProviderPackage.Settings {
@@ -21,10 +19,9 @@ export interface Settings extends ProviderPackage.Settings {
   readonly provider?: string
 }
 
-export type FamilyModelOptions = Omit<RouteDefaultsInput, "providerOptions"> &
+export type FamilyModelOptions = RouteDefaultsInput &
   ProviderAuthOption<"optional"> & {
     readonly baseURL?: string
-    readonly providerOptions?: OpenAIProviderOptionsInput
   }
 
 export const routes = [OpenAICompatibleChat.route]
@@ -40,8 +37,7 @@ export const configure = (input: GenericModelOptions) => {
   })
   return {
     id: ProviderID.make(provider),
-    model: (modelID: string | ModelID) =>
-      route.model<OpenAIProviderOptionsInput>({ id: modelID, provider: ProviderID.make(provider) }),
+    model: (modelID: string | ModelID) => route.model({ id: modelID, provider: ProviderID.make(provider) }),
     configure,
   }
 }
@@ -67,7 +63,7 @@ export const provider = {
   configure,
 }
 
-export const model: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (modelID, settings) =>
+export const model: ProviderPackage.Definition<Settings>["model"] = (modelID, settings) =>
   configure({
     apiKey: settings.apiKey,
     baseURL: settings.baseURL,

packages/ai/src/providers/openai.ts

@@ -86,15 +86,10 @@ export const configure = (input: Config = {}) => {
   const chatRoute = configuredRoute(OpenAIChat.route, input)
   const modelDefaults = defaults(input)
   const responses = (id: string | ModelID) =>
-    responsesRoute
-      .with(withOpenAIOptions(id, modelDefaults, { textVerbosity: true }))
-      .model<OpenAIProviderOptionsInput>({ id })
+    responsesRoute.with(withOpenAIOptions(id, modelDefaults, { textVerbosity: true })).model({ id })
   const responsesWebSocket = (id: string | ModelID) =>
-    responsesWebSocketRoute
-      .with(withOpenAIOptions(id, modelDefaults, { textVerbosity: true }))
-      .model<OpenAIProviderOptionsInput>({ id })
-  const chat = (id: string | ModelID) =>
-    chatRoute.with(withOpenAIOptions(id, modelDefaults)).model<OpenAIProviderOptionsInput>({ id })
+    responsesWebSocketRoute.with(withOpenAIOptions(id, modelDefaults, { textVerbosity: true })).model({ id })
+  const chat = (id: string | ModelID) => chatRoute.with(withOpenAIOptions(id, modelDefaults)).model({ id })
   const image = (modelID: string | ModelID) =>
     OpenAIImages.model({
       id: modelID,
@@ -137,17 +132,15 @@ const config = (settings: Settings): Config => {
   }
 }
 
-export const model: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (modelID, settings) => {
+export const model: ProviderPackage.Definition<Settings>["model"] = (modelID, settings) => {
   const configured = configure(config(settings))
   if (settings.transport === undefined || settings.transport === "http") return configured.responses(modelID)
   if (settings.transport === "websocket") return configured.responsesWebSocket(modelID)
   throw new Error(`Unsupported OpenAI Responses transport: ${String(settings.transport)}`)
 }
 
-export const chatModel: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (
-  modelID,
-  settings,
-) => configure(config(settings)).chat(modelID)
+export const chatModel: ProviderPackage.Definition<Settings>["model"] = (modelID, settings) =>
+  configure(config(settings)).chat(modelID)
 export const responses = provider.responses
 export const responsesWebSocket = provider.responsesWebSocket
 export const chat = provider.chat

packages/ai/src/providers/openrouter.ts

@@ -107,7 +107,7 @@ export const configure = (input: ModelOptions = {}) => {
   const route = configuredRoute(input)
   return {
     id,
-    model: (modelID: string | ModelID) => route.model<OpenRouterProviderOptionsInput>({ id: modelID }),
+    model: (modelID: string | ModelID) => route.model({ id: modelID }),
     configure,
   }
 }

packages/ai/src/providers/xai.ts

@@ -5,14 +5,12 @@ import * as OpenAICompatibleProfiles from "./openai-compatible-profile"
 import * as OpenAICompatibleChat from "../protocols/openai-compatible-chat"
 import * as OpenAIResponses from "../protocols/openai-responses"
 import { XAIImages } from "../protocols/xai-images"
-import type { OpenAIProviderOptionsInput } from "./openai-options"
 
 export const id = ProviderID.make("xai")
 
-export type ModelOptions = Omit<RouteDefaultsInput, "providerOptions"> &
+export type ModelOptions = RouteDefaultsInput &
   ProviderAuthOption<"optional"> & {
     readonly baseURL?: string
-    readonly providerOptions?: OpenAIProviderOptionsInput
   }
 
 export type { XAIImageOptions } from "../protocols/xai-images"
@@ -44,8 +42,8 @@ const configuredChatRoute = (input: ModelOptions) => {
 export const configure = (input: ModelOptions = {}) => {
   const responsesRoute = configuredResponsesRoute(input)
   const chatRoute = configuredChatRoute(input)
-  const responses = (modelID: string | ModelID) => responsesRoute.model<OpenAIProviderOptionsInput>({ id: modelID })
-  const chat = (modelID: string | ModelID) => chatRoute.model<OpenAIProviderOptionsInput>({ id: modelID })
+  const responses = (modelID: string | ModelID) => responsesRoute.model({ id: modelID })
+  const chat = (modelID: string | ModelID) => chatRoute.model({ id: modelID })
   const image = (modelID: string | ModelID) =>
     XAIImages.model({
       id: modelID,

packages/ai/src/route/client.ts

@@ -10,7 +10,7 @@ import { WebSocketExecutor } from "./transport"
 import type { Protocol } from "./protocol"
 import { applyCachePolicy } from "../cache-policy"
 import * as ProviderShared from "../protocols/shared"
-import type { LLMError, ProtocolID, ProviderOptions } from "../schema"
+import type { LLMError, PreparedRequestOf, ProtocolID, ProviderOptions } from "../schema"
 import {
   GenerationOptions,
   HttpOptions,
@@ -20,6 +20,7 @@ import {
   ModelLimits,
   LLMError as LLMErrorClass,
   LLMEvent,
+  PreparedRequest,
   ProviderID,
   mergeGenerationOptions,
   mergeHttpOptions,
@@ -45,7 +46,7 @@ export interface Route<Body, Prepared = unknown> {
   readonly defaults: RouteDefaults
   readonly body: RouteBody<Body>
   readonly with: (patch: RoutePatch<Body, Prepared>) => Route<Body, Prepared>
-  readonly model: <Options extends ProviderOptions = ProviderOptions>(input: RouteMappedModelInput) => Model<Options>
+  readonly model: (input: RouteMappedModelInput) => Model
   readonly prepareTransport: (body: Body, request: LLMRequest) => Effect.Effect<Prepared, LLMError>
   readonly streamPrepared: (
     prepared: Prepared,
@@ -92,12 +93,12 @@ export interface RoutePatch<Body, Prepared> extends RouteDefaultsInput {
 
 type RouteMappedModelInput = RouteModelInput | RouteRoutedModelInput
 
-const makeRouteModel = <Options extends ProviderOptions = ProviderOptions>(route: AnyRoute, mapped: RouteMappedModelInput) => {
+const makeRouteModel = (route: AnyRoute, mapped: RouteMappedModelInput) => {
   const provider = route.provider ?? ("provider" in mapped ? mapped.provider : undefined)
   if (!provider) throw new Error(`Route.model(${route.id}) requires a provider`)
   if (!endpointBaseURL(route.endpoint))
     throw new Error(`Route.model(${route.id}) requires an endpoint baseURL — configure it on the route first`)
-  return Model.make<Options>({
+  return Model.make({
     ...mapped,
     provider,
     route,
@@ -141,6 +142,17 @@ export const httpOptions = (input: HttpOptionsInput | undefined) => {
 }
 
 export interface Interface {
+  /**
+   * Compile a request through protocol body construction, validation, and HTTP
+   * preparation without sending it. Returns the prepared request including the
+   * provider-native body.
+   *
+   * Pass a `Body` type argument to statically expose the route's body
+   * shape (e.g. `prepare<OpenAIChatBody>(...)`) — the runtime body is
+   * identical, so this is a type-level assertion the caller makes about which
+   * route the request will resolve to.
+   */
+  readonly prepare: <Body = unknown>(request: LLMRequest) => Effect.Effect<PreparedRequestOf<Body>, LLMError>
   readonly stream: StreamMethod
   readonly generate: GenerateMethod
 }
@@ -284,8 +296,7 @@ function makeFromTransport<Body, Prepared, Frame, Event, State>(
           defaults: mergeRouteDefaults(route.defaults, defaults),
         })
       },
-      model: <Options extends ProviderOptions = ProviderOptions>(input: RouteMappedModelInput) =>
-        makeRouteModel<Options>(route, input),
+      model: (input) => makeRouteModel(route, input),
       prepareTransport: (body, request) =>
         routeInput.transport.prepare({
           body,
@@ -359,6 +370,9 @@ export function make<Body, Prepared, Frame, Event, State>(
   })
 }
 
+// `compile` is the important boundary: it turns a common `LLMRequest` into a
+// validated provider body plus transport-private prepared data, but does not
+// execute transport.
 const compile = Effect.fn("LLM.compile")(function* (request: LLMRequest) {
   const resolved = applyCachePolicy(resolveRequestOptions(request))
   const route = resolved.model.route
@@ -376,17 +390,17 @@ const compile = Effect.fn("LLM.compile")(function* (request: LLMRequest) {
   }
 })
 
-/** @internal Test-only projection of the execution compiler; not exported from package barrels. */
-export const compileRequest = Effect.fn("LLM.compileRequest")(function* (request: LLMRequest) {
+const prepareWith = Effect.fn("LLMClient.prepare")(function* (request: LLMRequest) {
   const compiled = yield* compile(request)
-  return {
+
+  return new PreparedRequest({
     id: compiled.request.id ?? "request",
     route: compiled.route.id,
     protocol: compiled.route.protocol,
     model: compiled.request.model,
     body: compiled.body,
     metadata: { transport: compiled.route.transport.id },
-  }
+  })
 })
 
 const streamRequestWith = (runtime: TransportRuntime) => (request: LLMRequest) =>
@@ -408,6 +422,9 @@ const generateWith = (stream: Interface["stream"]) =>
     )
   })
 
+export const prepare = <Body = unknown>(request: LLMRequest) =>
+  prepareWith(request) as Effect.Effect<PreparedRequestOf<Body>, LLMError>
+
 export function stream(request: LLMRequest): Stream.Stream<LLMEvent, LLMError> {
   return Stream.unwrap(
     Effect.gen(function* () {
@@ -436,7 +453,7 @@ export const layer: Layer.Layer<Service, never, RequestExecutor.Service> = Layer
       http: yield* RequestExecutor.Service,
       webSocket: Option.getOrUndefined(yield* Effect.serviceOption(WebSocketExecutor.Service)),
     })
-    return Service.of({ stream, generate: generateWith(stream) })
+    return Service.of({ prepare: prepareWith as Interface["prepare"], stream, generate: generateWith(stream) })
   }),
 )
 
@@ -445,6 +462,7 @@ export const Route = { make } as const
 export const LLMClient = {
   Service,
   layer,
+  prepare,
   stream,
   generate,
 } as const

packages/ai/src/schema/events.ts

@@ -1,5 +1,6 @@
 import { Schema } from "effect"
-import { ContentBlockID, FinishReason, ProviderMetadata, ToolCallID } from "./ids"
+import { ContentBlockID, FinishReason, ProtocolID, ProviderMetadata, RouteID, ToolCallID } from "./ids"
+import { ModelSchema } from "./options"
 import { Message, ToolCallPart, ToolOutput, ToolResultPart, ToolResultValue, type ContentPart } from "./messages"
 import { ProviderFailureClassification } from "./errors"
 
@@ -313,6 +314,29 @@ export const LLMEvent = Object.assign(llmEventTagged, {
 })
 export type LLMEvent = Schema.Schema.Type<typeof llmEventTagged>
 
+export class PreparedRequest extends Schema.Class<PreparedRequest>("LLM.PreparedRequest")({
+  id: Schema.String,
+  route: RouteID,
+  protocol: ProtocolID,
+  model: ModelSchema,
+  body: Schema.Unknown,
+  metadata: Schema.optional(Schema.Record(Schema.String, Schema.Unknown)),
+}) {}
+
+/**
+ * A `PreparedRequest` whose `body` is typed as `Body`. Use with the generic
+ * on `LLMClient.prepare<Body>(...)` when the caller knows which route their
+ * request will resolve to and wants its native shape statically exposed
+ * (debug UIs, request previews, plan rendering).
+ *
+ * The runtime body is identical — the route still emits `body: unknown` — so
+ * this is a type-level assertion the caller makes about what they expect to
+ * find. The prepare runtime does not validate the assertion.
+ */
+export type PreparedRequestOf<Body> = Omit<PreparedRequest, "body"> & {
+  readonly body: Body
+}
+
 const responseText = (events: ReadonlyArray<LLMEvent>) =>
   events
     .filter(LLMEvent.is.textDelta)

packages/ai/src/schema/options.ts

@@ -178,8 +178,7 @@ export namespace ModelCompatibility {
   export const make = (input: Input) => (input instanceof ModelCompatibility ? input : new ModelCompatibility(input))
 }
 
-export class Model<Options extends ProviderOptions = ProviderOptions> {
-  declare protected readonly _ProviderOptions: Options
+export class Model {
   readonly id: ModelID
   readonly provider: ProviderID
   readonly route: AnyRoute
@@ -194,8 +193,8 @@ export class Model<Options extends ProviderOptions = ProviderOptions> {
     this.compatibility = input.compatibility
   }
 
-  static make<Options extends ProviderOptions = ProviderOptions>(input: Model.Input) {
-    return new Model<Options>({
+  static make(input: Model.Input) {
+    return new Model({
       id: ModelID.make(input.id),
       provider: ProviderID.make(input.provider),
       route: input.route,
@@ -204,7 +203,7 @@ export class Model<Options extends ProviderOptions = ProviderOptions> {
     })
   }
 
-  static input<Options extends ProviderOptions>(model: Model<Options>): Model.ConstructorInput {
+  static input(model: Model): Model.ConstructorInput {
     return {
       id: model.id,
       provider: model.provider,
@@ -214,9 +213,9 @@ export class Model<Options extends ProviderOptions = ProviderOptions> {
     }
   }
 
-  static update<Options extends ProviderOptions>(model: Model<Options>, patch: Partial<Model.Input>) {
+  static update(model: Model, patch: Partial<Model.Input>) {
     if (Object.keys(patch).length === 0) return model
-    return Model.make<Options>({
+    return Model.make({
       ...Model.input(model),
       ...patch,
     })
@@ -242,8 +241,6 @@ export namespace Model {
 
 export type ModelInput = Model.Input
 
-export type ModelProviderOptions<SelectedModel> = SelectedModel extends Model<infer Options> ? Options : never
-
 export const ModelSchema = Schema.declare((value): value is Model => value instanceof Model, { expected: "LLM.Model" })
 
 export class CacheHint extends Schema.Class<CacheHint>("LLM.CacheHint")({

packages/ai/src/testing.ts

@@ -99,6 +99,7 @@ export const layer = (options: LayerOptions = {}) =>
         )
       }) as LLMClientShape["stream"]
       const client = LLMClient.Service.of({
+        prepare: () => Effect.die("TestLLM does not prepare provider-native requests"),
         stream,
         generate: (request) =>
           stream(request).pipe(

packages/ai/test/adapter.test.ts

@@ -2,7 +2,6 @@ import { describe, expect } from "bun:test"
 import { Effect, Schema, Stream } from "effect"
 import { LLM, LLMRequest, LLMResponse } from "../src"
 import { Route, Endpoint, LLMClient, Protocol, type FramingDef } from "../src/route"
-import { compileRequest } from "../src/route/client"
 import { Model } from "../src/schema"
 import { testEffect } from "./lib/effect"
 import { dynamicResponse } from "./lib/http"
@@ -140,7 +139,8 @@ describe("llm route", () => {
 
   it.effect("selects routes by model route value", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const llm = yield* LLMClient.Service
+      const prepared = yield* llm.prepare(
         LLMRequest.update(request, { model: updateModel(request.model, { route: configuredGemini }) }),
       )
 
@@ -173,7 +173,7 @@ describe("llm route", () => {
         framing: fakeFraming,
       })
 
-      const prepared = yield* compileRequest(
+      const prepared = yield* (yield* LLMClient.Service).prepare(
         LLMRequest.update(request, { model: updateModel(request.model, { route: duplicate }) }),
       )
 

packages/ai/test/cache-policy.test.ts

@@ -1,8 +1,7 @@
 import { describe, expect, test } from "bun:test"
 import { Effect } from "effect"
 import { CacheHint, LLM, Message } from "../src"
-import { Auth } from "../src/route"
-import { compileRequest } from "../src/route/client"
+import { Auth, LLMClient } from "../src/route"
 import { AmazonBedrock } from "../src/providers"
 import * as AnthropicMessages from "../src/protocols/anthropic-messages"
 import * as Gemini from "../src/protocols/gemini"
@@ -32,7 +31,7 @@ const geminiModel = Gemini.route
 describe("applyCachePolicy", () => {
   it.effect("undefined cache resolves to 'auto' (the recommended default)", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           model: anthropicModel,
           system: "You are concise.",
@@ -51,7 +50,7 @@ describe("applyCachePolicy", () => {
 
   it.effect("'auto' marks the last tool, first and last system parts, and final message boundary on Anthropic", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           model: anthropicModel,
           system: [
@@ -88,7 +87,7 @@ describe("applyCachePolicy", () => {
 
   it.effect("'auto' is a no-op on OpenAI (implicit caching protocol)", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           model: openaiModel,
           system: "Sys",
@@ -107,7 +106,7 @@ describe("applyCachePolicy", () => {
 
   it.effect("'auto' is a no-op on Gemini (out-of-band caching protocol)", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           model: geminiModel,
           system: "Sys",
@@ -124,7 +123,7 @@ describe("applyCachePolicy", () => {
 
   it.effect("'auto' on Bedrock emits cachePoint markers in the right places", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           model: bedrockModel,
           system: [
@@ -158,7 +157,7 @@ describe("applyCachePolicy", () => {
 
   it.effect("'none' disables auto placement even when manual hints exist", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           model: anthropicModel,
           system: "Sys",
@@ -177,7 +176,7 @@ describe("applyCachePolicy", () => {
 
   it.effect("granular object form: tools-only marks just tools", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           model: anthropicModel,
           system: "Sys",
@@ -196,7 +195,7 @@ describe("applyCachePolicy", () => {
 
   it.effect("auto policy preserves manual CacheHints on other parts", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           model: anthropicModel,
           system: [
@@ -242,7 +241,7 @@ describe("applyCachePolicy", () => {
       expect("cache" in tail ? tail.cache : undefined).toBeUndefined()
       expect(applyCachePolicy(applied)).toBe(applied)
 
-      const prepared = yield* compileRequest(request)
+      const prepared = yield* LLMClient.prepare(request)
 
       const body = prepared.body as {
         tools: Array<{ cache_control?: unknown }>
@@ -262,7 +261,7 @@ describe("applyCachePolicy", () => {
 
   it.effect("ttlSeconds in the policy flows through to wire markers", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           model: anthropicModel,
           system: "Sys",
@@ -279,7 +278,7 @@ describe("applyCachePolicy", () => {
 
   it.effect("messages: { tail: 2 } marks the last 2 message boundaries", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           model: anthropicModel,
           messages: [Message.user("u1"), Message.assistant("a1"), Message.user("u2"), Message.assistant("a2")],
@@ -297,7 +296,7 @@ describe("applyCachePolicy", () => {
 
   it.effect("'latest-assistant' marks the last assistant message", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           model: anthropicModel,
           messages: [Message.user("u1"), Message.assistant("a1"), Message.user("u2")],

packages/ai/test/llm-option-types.types.ts

@@ -1,47 +0,0 @@
-import { Schema } from "effect"
-import { LLM, type Model, type ModelProviderOptions, type ProviderOptions } from "../src"
-import { OpenAIChat } from "../src/protocols"
-
-interface ExampleOptions {
-  readonly [key: string]: unknown
-  readonly mode?: "fast" | "thorough"
-}
-
-type ExampleProviderOptions = ProviderOptions & {
-  readonly example?: ExampleOptions
-}
-
-const model = OpenAIChat.route
-  .with({ endpoint: { baseURL: "https://example.com/v1" } })
-  .model<ExampleProviderOptions>({ id: "example" })
-
-LLM.request({ model, prompt: "Hello", providerOptions: { example: { mode: "fast" } } })
-LLM.request({ model, prompt: "Hello", providerOptions: { future: { option: true } } })
-
-LLM.request({
-  model,
-  prompt: "Hello",
-  // @ts-expect-error Known provider options preserve their value types.
-  providerOptions: { example: { mode: "slow" } },
-})
-
-LLM.generateObject({
-  model,
-  prompt: "Hello",
-  schema: Schema.Struct({ answer: Schema.String }),
-  providerOptions: { example: { mode: "thorough" } },
-})
-
-LLM.generateObject({
-  model,
-  prompt: "Hello",
-  jsonSchema: { type: "object" },
-  // @ts-expect-error Dynamic object generation uses the selected model's provider options.
-  providerOptions: { example: { mode: false } },
-})
-
-declare const generic: Model
-LLM.request({ model: generic, prompt: "Hello", providerOptions: { arbitrary: { option: true } } })
-
-const options: ModelProviderOptions<typeof model> = { example: { mode: "fast" } }
-void options

packages/ai/test/prepare.test.ts

@@ -4,7 +4,6 @@ import { HttpClientRequest } from "effect/unstable/http"
 import { LLM, mergeProviderOptions } from "../src"
 import { AnthropicMessages, OpenAIChat } from "../src/protocols"
 import { Auth, LLMClient } from "../src/route"
-import { compileRequest } from "../src/route/client"
 import { it } from "./lib/effect"
 import { dynamicResponse } from "./lib/http"
 import { deltaChunk } from "./lib/openai-chunks"
@@ -45,7 +44,7 @@ describe("request option precedence", () => {
     })
   })
 
-  it.effect("compiles bodies with route defaults, model defaults, and call options in order", () =>
+  it.effect("prepares bodies with route defaults, model defaults, and call options in order", () =>
     Effect.gen(function* () {
       const route = OpenAIChat.route.with({
         endpoint: { baseURL: "https://api.openai.test/v1/" },
@@ -60,7 +59,7 @@ describe("request option precedence", () => {
           providerOptions: { openai: { reasoningEffort: "medium" } },
         },
       })
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
         LLM.request({
           model,
           prompt: "Say hello.",
@@ -142,7 +141,7 @@ describe("request option precedence", () => {
       const model = OpenAIChat.route
         .with({ endpoint: { baseURL: "https://api.openai.test/v1/" }, auth: Auth.bearer("test") })
         .model({ id: "gpt-4o-mini" })
-      const error = yield* compileRequest(
+      const error = yield* LLMClient.prepare(
         LLM.request({
           model,
           prompt: "Say hello.",
@@ -165,8 +164,10 @@ describe("request option precedence", () => {
         limits: { output: 128 },
       })
       const model = route.model({ id: "claude-sonnet-4-5", defaults: { limits: { output: 64 } } })
-      const withoutMaxTokens = yield* compileRequest(LLM.request({ model, prompt: "Say hello.", cache: "none" }))
-      const withMaxTokens = yield* compileRequest(
+      const withoutMaxTokens = yield* LLMClient.prepare<AnthropicMessages.AnthropicMessagesBody>(
+        LLM.request({ model, prompt: "Say hello.", cache: "none" }),
+      )
+      const withMaxTokens = yield* LLMClient.prepare<AnthropicMessages.AnthropicMessagesBody>(
         LLM.request({ model, prompt: "Say hello.", cache: "none", generation: { maxTokens: 32 } }),
       )
 

packages/ai/test/provider-options/anthropic-compatible.types.ts

@@ -1,13 +0,0 @@
-import { LLM } from "../../src"
-import { AnthropicCompatible } from "../../src/providers"
-
-const model = AnthropicCompatible.configure({ baseURL: "https://example.com" }).model("claude")
-
-LLM.request({ model, prompt: "Hello", providerOptions: { anthropic: { effort: "high" } } })
-
-LLM.request({
-  model,
-  prompt: "Hello",
-  // @ts-expect-error Anthropic effort must be a string.
-  providerOptions: { anthropic: { effort: 1 } },
-})

packages/ai/test/provider-options/anthropic.types.ts

@@ -1,13 +0,0 @@
-import { LLM } from "../../src"
-import { Anthropic } from "../../src/providers"
-
-const model = Anthropic.provider.model("claude-sonnet-4-5")
-
-LLM.request({ model, prompt: "Hello", providerOptions: { anthropic: { thinking: { type: "adaptive" } } } })
-
-LLM.request({
-  model,
-  prompt: "Hello",
-  // @ts-expect-error Anthropic thinking modes are a fixed union.
-  providerOptions: { anthropic: { thinking: { type: "automatic" } } },
-})

packages/ai/test/provider-options/azure.types.ts

@@ -1,13 +0,0 @@
-import { LLM } from "../../src"
-import { Azure } from "../../src/providers"
-
-const model = Azure.configure({ resourceName: "example" }).responses("deployment")
-
-LLM.request({ model, prompt: "Hello", providerOptions: { openai: { store: false } } })
-
-LLM.request({
-  model,
-  prompt: "Hello",
-  // @ts-expect-error Azure OpenAI store must be boolean.
-  providerOptions: { openai: { store: "false" } },
-})

packages/ai/test/provider-options/cloudflare.types.ts

@@ -1,13 +0,0 @@
-import { LLM } from "../../src"
-import { CloudflareWorkersAI } from "../../src/providers"
-
-const model = CloudflareWorkersAI.configure({ accountId: "account", apiKey: "test" }).model("model")
-
-LLM.request({ model, prompt: "Hello", providerOptions: { openai: { promptCacheKey: "cache" } } })
-
-LLM.request({
-  model,
-  prompt: "Hello",
-  // @ts-expect-error Cloudflare's OpenAI-compatible prompt cache key must be a string.
-  providerOptions: { openai: { promptCacheKey: 1 } },
-})

packages/ai/test/provider-options/github-copilot.types.ts

@@ -1,13 +0,0 @@
-import { LLM } from "../../src"
-import { GitHubCopilot } from "../../src/providers"
-
-const model = GitHubCopilot.configure({ baseURL: "https://example.com" }).model("gpt-5")
-
-LLM.request({ model, prompt: "Hello", providerOptions: { openai: { reasoningSummary: "auto" } } })
-
-LLM.request({
-  model,
-  prompt: "Hello",
-  // @ts-expect-error Copilot reasoning summaries use the OpenAI union.
-  providerOptions: { openai: { reasoningSummary: "full" } },
-})

packages/ai/test/provider-options/google-vertex-chat.types.ts

@@ -1,13 +0,0 @@
-import { LLM } from "../../src"
-import { GoogleVertexChat } from "../../src/providers"
-
-const model = GoogleVertexChat.configure({ accessToken: "test", project: "project" }).model("gemini")
-
-LLM.request({ model, prompt: "Hello", providerOptions: { openai: { serviceTier: "priority" } } })
-
-LLM.request({
-  model,
-  prompt: "Hello",
-  // @ts-expect-error Vertex OpenAI-compatible service tiers use the OpenAI union.
-  providerOptions: { openai: { serviceTier: "premium" } },
-})

packages/ai/test/provider-options/google-vertex-messages.types.ts

@@ -1,13 +0,0 @@
-import { LLM } from "../../src"
-import { GoogleVertexMessages } from "../../src/providers"
-
-const model = GoogleVertexMessages.configure({ accessToken: "test", project: "project" }).model("claude")
-
-LLM.request({ model, prompt: "Hello", providerOptions: { anthropic: { effort: "medium" } } })
-
-LLM.request({
-  model,
-  prompt: "Hello",
-  // @ts-expect-error Vertex Anthropic effort must be a string.
-  providerOptions: { anthropic: { effort: false } },
-})

packages/ai/test/provider-options/google-vertex-responses.types.ts

@@ -1,13 +0,0 @@
-import { LLM } from "../../src"
-import { GoogleVertexResponses } from "../../src/providers"
-
-const model = GoogleVertexResponses.configure({ accessToken: "test", project: "project" }).model("gemini")
-
-LLM.request({ model, prompt: "Hello", providerOptions: { openresponses: { textVerbosity: "high" } } })
-
-LLM.request({
-  model,
-  prompt: "Hello",
-  // @ts-expect-error Vertex Responses verbosity uses the Open Responses union.
-  providerOptions: { openresponses: { textVerbosity: "verbose" } },
-})

packages/ai/test/provider-options/google-vertex.types.ts

@@ -1,17 +0,0 @@
-import { LLM } from "../../src"
-import { GoogleVertex } from "../../src/providers"
-
-const model = GoogleVertex.provider.configure({ apiKey: "test" }).model("gemini-2.5-pro")
-
-LLM.request({
-  model,
-  prompt: "Hello",
-  providerOptions: { gemini: { thinkingConfig: { includeThoughts: true } } },
-})
-
-LLM.request({
-  model,
-  prompt: "Hello",
-  // @ts-expect-error Vertex Gemini includeThoughts must be boolean.
-  providerOptions: { gemini: { thinkingConfig: { includeThoughts: "yes" } } },
-})

packages/ai/test/provider-options/google.types.ts

@@ -1,17 +0,0 @@
-import { LLM } from "../../src"
-import { Google } from "../../src/providers"
-
-const model = Google.provider.model("gemini-2.5-pro")
-
-LLM.request({
-  model,
-  prompt: "Hello",
-  providerOptions: { gemini: { thinkingConfig: { thinkingBudget: 1024 } } },
-})
-
-LLM.request({
-  model,
-  prompt: "Hello",
-  // @ts-expect-error Gemini thinking budgets must be numeric.
-  providerOptions: { gemini: { thinkingConfig: { thinkingBudget: "large" } } },
-})

packages/ai/test/provider-options/openai-compatible-responses.types.ts

@@ -1,13 +0,0 @@
-import { LLM } from "../../src"
-import { OpenAICompatibleResponses } from "../../src/providers"
-
-const model = OpenAICompatibleResponses.configure({ baseURL: "https://example.com" }).model("model")
-
-LLM.request({ model, prompt: "Hello", providerOptions: { openresponses: { reasoningSummary: "detailed" } } })
-
-LLM.request({
-  model,
-  prompt: "Hello",
-  // @ts-expect-error Open Responses reasoning summaries use a fixed union.
-  providerOptions: { openresponses: { reasoningSummary: "full" } },
-})

packages/ai/test/provider-options/openai-compatible.types.ts

@@ -1,13 +0,0 @@
-import { LLM } from "../../src"
-import { OpenAICompatible } from "../../src/providers"
-
-const model = OpenAICompatible.deepseek.model("deepseek-chat")
-
-LLM.request({ model, prompt: "Hello", providerOptions: { openai: { store: false } } })
-
-LLM.request({
-  model,
-  prompt: "Hello",
-  // @ts-expect-error OpenAI-compatible store must be boolean.
-  providerOptions: { openai: { store: "false" } },
-})

packages/ai/test/provider-options/openai.types.ts

@@ -1,13 +0,0 @@
-import { LLM } from "../../src"
-import { OpenAI } from "../../src/providers"
-
-const model = OpenAI.responses("gpt-5")
-
-LLM.request({ model, prompt: "Hello", providerOptions: { openai: { reasoningEffort: "high" } } })
-
-LLM.request({
-  model,
-  prompt: "Hello",
-  // @ts-expect-error OpenAI reasoning effort must be a string.
-  providerOptions: { openai: { reasoningEffort: 1 } },
-})

packages/ai/test/provider-options/openrouter.types.ts

@@ -1,13 +0,0 @@
-import { LLM } from "../../src"
-import { OpenRouter } from "../../src/providers"
-
-const model = OpenRouter.provider.model("anthropic/claude-sonnet-4.5")
-
-LLM.request({ model, prompt: "Hello", providerOptions: { openrouter: { usage: true } } })
-
-LLM.request({
-  model,
-  prompt: "Hello",
-  // @ts-expect-error OpenRouter usage must be boolean or an option record.
-  providerOptions: { openrouter: { usage: "yes" } },
-})

packages/ai/test/provider-options/xai.types.ts

@@ -1,13 +0,0 @@
-import { LLM } from "../../src"
-import { XAI } from "../../src/providers"
-
-const model = XAI.provider.model("grok-4")
-
-LLM.request({ model, prompt: "Hello", providerOptions: { openai: { reasoningEffort: "high" } } })
-
-LLM.request({
-  model,
-  prompt: "Hello",
-  // @ts-expect-error xAI's OpenAI-compatible reasoning effort must be a string.
-  providerOptions: { openai: { reasoningEffort: true } },
-})

packages/ai/test/provider/anthropic-messages.test.ts

@@ -3,7 +3,6 @@ import { Effect } from "effect"
 import { HttpClientRequest } from "effect/unstable/http"
 import { CacheHint, LLM, LLMError, LLMRequest, Message, ToolCallPart, ToolDefinition, Usage } from "../../src"
 import { Auth, LLMClient } from "../../src/route"
-import { compileRequest } from "../../src/route/client"
 import * as AnthropicMessages from "../../src/protocols/anthropic-messages"
 import { continuationRequest, nativeAnthropicMessagesContinuation } from "../continuation-scenarios"
 import { it } from "../lib/effect"
@@ -45,7 +44,7 @@ const expectToolResult = (body: AnthropicMessages.AnthropicMessagesBody): Anthro
 describe("Anthropic Messages route", () => {
   it.effect("prepares Anthropic Messages target", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(request)
+      const prepared = yield* LLMClient.prepare(request)
 
       expect(prepared.body).toEqual({
         model: "claude-sonnet-4-5",
@@ -60,7 +59,7 @@ describe("Anthropic Messages route", () => {
 
   it.effect("lowers adaptive thinking settings with effort", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<AnthropicMessages.AnthropicMessagesBody>(
         LLMRequest.update(request, {
           providerOptions: {
             anthropic: { thinking: { type: "adaptive", display: "summarized" }, effort: "low" },
@@ -77,17 +76,17 @@ describe("Anthropic Messages route", () => {
 
   it.effect("normalizes enabled and disabled thinking settings", () =>
     Effect.gen(function* () {
-      const enabled = yield* compileRequest(
+      const enabled = yield* LLMClient.prepare<AnthropicMessages.AnthropicMessagesBody>(
         LLMRequest.update(request, {
           providerOptions: { anthropic: { thinking: { type: "enabled", budgetTokens: 1_024 } } },
         }),
       )
-      const legacy = yield* compileRequest(
+      const legacy = yield* LLMClient.prepare<AnthropicMessages.AnthropicMessagesBody>(
         LLMRequest.update(request, {
           providerOptions: { anthropic: { thinking: { type: "enabled", budget_tokens: 2_048 } } },
         }),
       )
-      const disabled = yield* compileRequest(
+      const disabled = yield* LLMClient.prepare<AnthropicMessages.AnthropicMessagesBody>(
         LLMRequest.update(request, {
           providerOptions: { anthropic: { thinking: { type: "disabled" } } },
         }),
@@ -101,7 +100,7 @@ describe("Anthropic Messages route", () => {
 
   it.effect("rejects enabled thinking without a budget", () =>
     Effect.gen(function* () {
-      const error = yield* compileRequest(
+      const error = yield* LLMClient.prepare(
         LLMRequest.update(request, {
           providerOptions: { anthropic: { thinking: { type: "enabled" } } },
         }),
@@ -113,7 +112,7 @@ describe("Anthropic Messages route", () => {
 
   it.effect("lowers chronological system updates natively for Claude Opus 4.8 with cache hints", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<AnthropicMessages.AnthropicMessagesBody>(
         LLM.request({
           model: opus48,
           messages: [
@@ -138,7 +137,7 @@ describe("Anthropic Messages route", () => {
 
   it.effect("lowers chronological system updates to wrapped user text for unsupported Anthropic models", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<AnthropicMessages.AnthropicMessagesBody>(
         LLM.request({
           model,
           messages: [
@@ -165,7 +164,7 @@ describe("Anthropic Messages route", () => {
 
   it.effect("rejects non-text chronological system update content before send", () =>
     Effect.gen(function* () {
-      const error = yield* compileRequest(
+      const error = yield* LLMClient.prepare(
         LLM.request({
           model: opus48,
           messages: [
@@ -182,7 +181,7 @@ describe("Anthropic Messages route", () => {
   it.effect("falls back for unsupported native chronological system update placement", () =>
     Effect.gen(function* () {
       expect(
-        (yield* compileRequest(
+        (yield* LLMClient.prepare<AnthropicMessages.AnthropicMessagesBody>(
           LLM.request({
             model: opus48,
             messages: [Message.assistant("Plain."), Message.system("After plain assistant.")],
@@ -197,11 +196,12 @@ describe("Anthropic Messages route", () => {
         },
       ])
       expect(
-        (yield* compileRequest(LLM.request({ model: opus48, messages: [Message.system("First.")], cache: "none" })))
-          .body.messages,
+        (yield* LLMClient.prepare<AnthropicMessages.AnthropicMessagesBody>(
+          LLM.request({ model: opus48, messages: [Message.system("First.")], cache: "none" }),
+        )).body.messages,
       ).toEqual([{ role: "user", content: [{ type: "text", text: "<system-update>\nFirst.\n</system-update>" }] }])
       expect(
-        (yield* compileRequest(
+        (yield* LLMClient.prepare<AnthropicMessages.AnthropicMessagesBody>(
           LLM.request({
             model: opus48,
             messages: [Message.user("Before."), Message.system("One."), Message.system("Two.")],
@@ -223,7 +223,7 @@ describe("Anthropic Messages route", () => {
 
   it.effect("rejects a system update between a local tool call and its result", () =>
     Effect.gen(function* () {
-      const error = yield* compileRequest(
+      const error = yield* LLMClient.prepare(
         LLM.request({
           model: opus48,
           messages: [
@@ -242,7 +242,7 @@ describe("Anthropic Messages route", () => {
 
   it.effect("prepares tool call and tool result messages", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<AnthropicMessages.AnthropicMessagesBody>(
         LLM.request({
           id: "req_tool_result",
           model,
@@ -273,7 +273,7 @@ describe("Anthropic Messages route", () => {
 
   it.effect("keeps tools and sends tool_choice none", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<AnthropicMessages.AnthropicMessagesBody>(
         LLM.request({
           id: "req_tool_choice_none",
           model,
@@ -303,7 +303,7 @@ describe("Anthropic Messages route", () => {
   // not JSON-stringified into `tool_result.content`.
   it.effect("lowers media tool-result content as structured blocks", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<AnthropicMessages.AnthropicMessagesBody>(
         LLM.request({
           id: "req_tool_result_image",
           model,
@@ -335,7 +335,7 @@ describe("Anthropic Messages route", () => {
 
   it.effect("lowers single-image tool-result content as a structured image block", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<AnthropicMessages.AnthropicMessagesBody>(
         LLM.request({
           id: "req_tool_result_image_only",
           model,
@@ -360,7 +360,7 @@ describe("Anthropic Messages route", () => {
 
   it.effect("rejects unsupported media in tool-result content with a clear error", () =>
     Effect.gen(function* () {
-      const error = yield* compileRequest(
+      const error = yield* LLMClient.prepare(
         LLM.request({
           id: "req_tool_result_unsupported_media",
           model,
@@ -384,7 +384,7 @@ describe("Anthropic Messages route", () => {
 
   it.effect("prepares the composed native continuation request", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<AnthropicMessages.AnthropicMessagesBody>(
         continuationRequest({
           id: "req_native_continuation_anthropic",
           model,
@@ -428,7 +428,7 @@ describe("Anthropic Messages route", () => {
 
   it.effect("lowers preserved Anthropic reasoning signature metadata", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           model,
           messages: [
@@ -447,7 +447,7 @@ describe("Anthropic Messages route", () => {
 
   it.effect("round-trips redacted thinking as redacted_thinking blocks", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           model,
           messages: [
@@ -628,7 +628,9 @@ describe("Anthropic Messages route", () => {
         { type: "reasoning", text: "", providerMetadata: { anthropic: { signature: "sig_1" } } },
       ])
 
-      const prepared = yield* compileRequest(LLM.request({ model, messages: [response.message], cache: "none" }))
+      const prepared = yield* LLMClient.prepare<AnthropicMessages.AnthropicMessagesBody>(
+        LLM.request({ model, messages: [response.message], cache: "none" }),
+      )
       expect(prepared.body.messages).toEqual([
         { role: "assistant", content: [{ type: "thinking", thinking: "", signature: "sig_1" }] },
       ])
@@ -771,7 +773,7 @@ describe("Anthropic Messages route", () => {
           ),
         ),
       )
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<AnthropicMessages.AnthropicMessagesBody>(
         LLM.request({
           model,
           messages: [
@@ -1131,7 +1133,7 @@ describe("Anthropic Messages route", () => {
 
   it.effect("round-trips provider-executed assistant content into server tool blocks", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           id: "req_round_trip",
           model,
@@ -1182,7 +1184,7 @@ describe("Anthropic Messages route", () => {
 
   it.effect("rejects round-trip for unknown server tool names", () =>
     Effect.gen(function* () {
-      const error = yield* compileRequest(
+      const error = yield* LLMClient.prepare(
         LLM.request({
           id: "req_unknown_server_tool",
           model,
@@ -1259,7 +1261,7 @@ describe("Anthropic Messages route", () => {
 
   it.effect("maps ttlSeconds >= 3600 to cache_control ttl: '1h'", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           model,
           system: { type: "text", text: "system", cache: new CacheHint({ type: "ephemeral", ttlSeconds: 3600 }) },
@@ -1275,7 +1277,7 @@ describe("Anthropic Messages route", () => {
 
   it.effect("emits cache_control on tool definitions and tool-result blocks", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           model,
           tools: [
@@ -1316,7 +1318,7 @@ describe("Anthropic Messages route", () => {
   it.effect("drops cache_control breakpoints past the 4-per-request cap", () =>
     Effect.gen(function* () {
       const hint = new CacheHint({ type: "ephemeral" })
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           model,
           system: [
@@ -1342,7 +1344,7 @@ describe("Anthropic Messages route", () => {
   it.effect("spends breakpoint budget on tools before system before messages", () =>
     Effect.gen(function* () {
       const hint = new CacheHint({ type: "ephemeral" })
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           model,
           tools: [

packages/ai/test/provider/bedrock-converse.test.ts

@@ -13,7 +13,6 @@ import {
   ToolDefinition,
 } from "../../src"
 import { LLMClient } from "../../src/route"
-import { compileRequest } from "../../src/route/client"
 import { AmazonBedrock } from "../../src/providers"
 import * as BedrockConverse from "../../src/protocols/bedrock-converse"
 import { it } from "../lib/effect"
@@ -102,7 +101,7 @@ const baseRequest = LLM.request({
 describe("Bedrock Converse route", () => {
   it.effect("prepares Converse target with system, inference config, and messages", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(baseRequest)
+      const prepared = yield* LLMClient.prepare(baseRequest)
 
       expect(prepared.body).toEqual({
         modelId: "anthropic.claude-3-5-sonnet-20240620-v1:0",
@@ -115,7 +114,7 @@ describe("Bedrock Converse route", () => {
 
   it.effect("passes topK through additionalModelRequestFields as top_k", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<BedrockConverse.BedrockConverseBody>(
         LLMRequest.update(baseRequest, {
           generation: GenerationOptions.make({ maxTokens: 64, temperature: 0, topK: 40 }),
         }),
@@ -130,14 +129,14 @@ describe("Bedrock Converse route", () => {
 
   it.effect("omits additionalModelRequestFields when topK is unset", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(baseRequest)
+      const prepared = yield* LLMClient.prepare<BedrockConverse.BedrockConverseBody>(baseRequest)
       expect(prepared.body.additionalModelRequestFields).toBeUndefined()
     }),
   )
 
   it.effect("lowers chronological system updates to wrapped user text in order", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<BedrockConverse.BedrockConverseBody>(
         LLM.request({
           model,
           messages: [Message.user("Before."), Message.system("Update."), Message.assistant("After.")],
@@ -154,7 +153,7 @@ describe("Bedrock Converse route", () => {
 
   it.effect("prepares tool config with toolSpec and toolChoice", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLMRequest.update(baseRequest, {
           tools: [
             ToolDefinition.make({
@@ -188,7 +187,7 @@ describe("Bedrock Converse route", () => {
 
   it.effect("keeps tools and omits the unsupported choice when tool choice is none", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLMRequest.update(baseRequest, {
           tools: [
             ToolDefinition.make({
@@ -218,7 +217,7 @@ describe("Bedrock Converse route", () => {
 
   it.effect("lowers assistant tool-call + tool-result message history", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           id: "req_history",
           model,
@@ -257,7 +256,7 @@ describe("Bedrock Converse route", () => {
 
   it.effect("lowers image content in tool-result messages", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           id: "req_tool_image",
           model,
@@ -492,7 +491,7 @@ describe("Bedrock Converse route", () => {
         providerMetadata: { bedrock: { signature: "sig_1" } },
       })
 
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<BedrockConverse.BedrockConverseBody>(
         LLM.request({
           model,
           messages: [
@@ -547,7 +546,9 @@ describe("Bedrock Converse route", () => {
         },
       ])
 
-      const prepared = yield* compileRequest(LLM.request({ model, messages: [response.message], cache: "none" }))
+      const prepared = yield* LLMClient.prepare<BedrockConverse.BedrockConverseBody>(
+        LLM.request({ model, messages: [response.message], cache: "none" }),
+      )
       expect(prepared.body.messages).toEqual([
         {
           role: "assistant",
@@ -638,7 +639,7 @@ describe("Bedrock Converse route", () => {
         text: "",
         providerMetadata: { bedrock: { redactedData } },
       })
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<BedrockConverse.BedrockConverseBody>(
         LLM.request({
           model,
           messages: [
@@ -753,7 +754,7 @@ describe("Bedrock Converse route", () => {
           secretAccessKey: "wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY",
         },
       }).model("anthropic.claude-3-5-sonnet-20240620-v1:0")
-      const prepared = yield* compileRequest(LLMRequest.update(baseRequest, { model: signed }))
+      const prepared = yield* LLMClient.prepare(LLMRequest.update(baseRequest, { model: signed }))
 
       expect(prepared.route).toBe("bedrock-converse")
       expect(prepared.model).toBe(signed)
@@ -763,7 +764,7 @@ describe("Bedrock Converse route", () => {
   it.effect("emits cachePoint markers after system, user-text, and assistant-text with cache hints", () =>
     Effect.gen(function* () {
       const cache = new CacheHint({ type: "ephemeral" })
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           id: "req_cache",
           model,
@@ -795,7 +796,7 @@ describe("Bedrock Converse route", () => {
 
   it.effect("does not emit cachePoint when no cache hint is set", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(baseRequest)
+      const prepared = yield* LLMClient.prepare(baseRequest)
       expect(prepared.body).toMatchObject({
         system: [{ text: "You are concise." }],
         messages: [{ role: "user", content: [{ text: "Say hello." }] }],
@@ -805,7 +806,7 @@ describe("Bedrock Converse route", () => {
 
   it.effect("lowers image media into Bedrock image blocks", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           id: "req_image",
           model,
@@ -842,7 +843,7 @@ describe("Bedrock Converse route", () => {
 
   it.effect("base64-encodes Uint8Array image bytes", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           id: "req_image_bytes",
           model,
@@ -864,7 +865,7 @@ describe("Bedrock Converse route", () => {
 
   it.effect("lowers document media into Bedrock document blocks with format and name", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           id: "req_doc",
           model,
@@ -896,7 +897,7 @@ describe("Bedrock Converse route", () => {
 
   it.effect("requires names for document media", () =>
     Effect.gen(function* () {
-      const error = yield* compileRequest(
+      const error = yield* LLMClient.prepare(
         LLM.request({
           model,
           messages: [Message.user({ type: "media", mediaType: "application/pdf", data: "UERGREFUQQ==" })],
@@ -909,7 +910,7 @@ describe("Bedrock Converse route", () => {
 
   it.effect("passes named document-only messages through for provider validation", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<BedrockConverse.BedrockConverseBody>(
         LLM.request({
           model,
           cache: "none",
@@ -935,7 +936,7 @@ describe("Bedrock Converse route", () => {
 
   it.effect("lowers document media in tool results", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<BedrockConverse.BedrockConverseBody>(
         LLM.request({
           model,
           cache: "none",
@@ -987,7 +988,7 @@ describe("Bedrock Converse route", () => {
 
   it.effect("rejects unsupported image media types", () =>
     Effect.gen(function* () {
-      const error = yield* compileRequest(
+      const error = yield* LLMClient.prepare(
         LLM.request({
           id: "req_bad_image",
           model,
@@ -1001,7 +1002,7 @@ describe("Bedrock Converse route", () => {
 
   it.effect("rejects unsupported document media types", () =>
     Effect.gen(function* () {
-      const error = yield* compileRequest(
+      const error = yield* LLMClient.prepare(
         LLM.request({
           id: "req_bad_doc",
           model,
@@ -1016,7 +1017,7 @@ describe("Bedrock Converse route", () => {
   it.effect("maps ttlSeconds >= 3600 to cachePoint ttl: '1h'", () =>
     Effect.gen(function* () {
       const cache = new CacheHint({ type: "ephemeral", ttlSeconds: 3600 })
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           model,
           system: [{ type: "text", text: "system", cache }],
@@ -1033,7 +1034,7 @@ describe("Bedrock Converse route", () => {
   it.effect("appends cachePoint after marked tool definitions and tool-result blocks", () =>
     Effect.gen(function* () {
       const cache = new CacheHint({ type: "ephemeral" })
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           model,
           tools: [{ name: "lookup", description: "lookup", inputSchema: { type: "object", properties: {} }, cache }],
@@ -1065,7 +1066,7 @@ describe("Bedrock Converse route", () => {
   it.effect("drops cachePoint markers past the 4-per-request cap", () =>
     Effect.gen(function* () {
       const cache = new CacheHint({ type: "ephemeral" })
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           model,
           system: [

packages/ai/test/provider/cloudflare.test.ts

@@ -3,7 +3,7 @@ import { ConfigProvider, Effect, Schema } from "effect"
 import { HttpClientRequest } from "effect/unstable/http"
 import { LLM, LLMEvent } from "../../src"
 import { CloudflareAIGateway, CloudflareWorkersAI } from "../../src/providers/cloudflare"
-import { compileRequest } from "../../src/route/client"
+import { LLMClient } from "../../src/route"
 import { it } from "../lib/effect"
 import { dynamicResponse } from "../lib/http"
 import { sseEvents } from "../lib/sse"
@@ -34,7 +34,7 @@ describe("Cloudflare", () => {
       })
       expect(model.route.endpoint.baseURL).toBe("https://gateway.ai.cloudflare.com/v1/test-account/test-gateway/compat")
 
-      const prepared = yield* compileRequest(LLM.request({ model, prompt: "Say hello." }))
+      const prepared = yield* LLMClient.prepare(LLM.request({ model, prompt: "Say hello." }))
 
       expect(prepared.route).toBe("cloudflare-ai-gateway")
       expect(prepared.body).toMatchObject({
@@ -129,7 +129,7 @@ describe("Cloudflare", () => {
         openai: { reasoningField: "reasoning", reasoningDetails: merged },
       })
 
-      const replay = yield* compileRequest(LLM.request({ model, messages: [response.message] }))
+      const replay = yield* LLMClient.prepare(LLM.request({ model, messages: [response.message] }))
       expect(replay.body.messages).toEqual([
         { role: "assistant", content: "Hello", reasoning: "Thinking", reasoning_details: merged },
       ])
@@ -180,7 +180,7 @@ describe("Cloudflare", () => {
 
   it.effect("allows a fully configured baseURL override", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           model: CloudflareAIGateway.configure({
             baseURL: "https://gateway.proxy.test/v1/custom/compat",
@@ -208,7 +208,7 @@ describe("Cloudflare", () => {
       })
       expect(model.route.endpoint.baseURL).toBe("https://api.cloudflare.com/client/v4/accounts/test-account/ai/v1")
 
-      const prepared = yield* compileRequest(LLM.request({ model, prompt: "Say hello." }))
+      const prepared = yield* LLMClient.prepare(LLM.request({ model, prompt: "Say hello." }))
 
       expect(prepared.route).toBe("cloudflare-workers-ai")
       expect(prepared.body).toMatchObject({

packages/ai/test/provider/gemini.test.ts

@@ -2,7 +2,6 @@ import { describe, expect } from "bun:test"
 import { Effect } from "effect"
 import { LLM, LLMError, LLMRequest, Message, ToolCallPart, ToolDefinition, Usage } from "../../src"
 import { Auth, LLMClient } from "../../src/route"
-import { compileRequest } from "../../src/route/client"
 import * as Gemini from "../../src/protocols/gemini"
 import { ProviderShared } from "../../src/protocols/shared"
 import { it } from "../lib/effect"
@@ -27,7 +26,7 @@ const request = LLM.request({
 describe("Gemini route", () => {
   it.effect("prepares Gemini target", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(request)
+      const prepared = yield* LLMClient.prepare(request)
 
       expect(prepared.body).toEqual({
         contents: [{ role: "user", parts: [{ text: "Say hello." }] }],
@@ -39,12 +38,12 @@ describe("Gemini route", () => {
 
   it.effect("normalizes Gemini thinking options", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<Gemini.GeminiBody>(
         LLMRequest.update(request, {
           providerOptions: { gemini: { thinkingConfig: { thinkingBudget: 0, includeThoughts: false } } },
         }),
       )
-      const filtered = yield* compileRequest(
+      const filtered = yield* LLMClient.prepare<Gemini.GeminiBody>(
         LLMRequest.update(request, {
           providerOptions: { gemini: { thinkingConfig: { thinkingBudget: "invalid", includeThoughts: false } } },
         }),
@@ -60,7 +59,7 @@ describe("Gemini route", () => {
 
   it.effect("lowers chronological system updates to wrapped user text in order", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<Gemini.GeminiBody>(
         LLM.request({
           model,
           messages: [Message.user("Before."), Message.system("Update."), Message.assistant("After.")],
@@ -76,7 +75,7 @@ describe("Gemini route", () => {
 
   it.effect("prepares multimodal user input and tool history", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           id: "req_tool_result",
           model,
@@ -144,7 +143,7 @@ describe("Gemini route", () => {
 
   it.effect("continues media tool results as inline model input without base64 text", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<Gemini.GeminiBody>(
         LLM.request({
           model,
           messages: [
@@ -189,7 +188,7 @@ describe("Gemini route", () => {
 
   it.effect("strips matching data URLs to raw base64 inlineData", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<Gemini.GeminiBody>(
         LLM.request({
           model,
           messages: [
@@ -230,7 +229,7 @@ describe("Gemini route", () => {
   ] as const)
     it.effect(`rejects ${name}`, () =>
       Effect.gen(function* () {
-        const error = yield* compileRequest(
+        const error = yield* LLMClient.prepare(
           LLM.request({ model, messages: [Message.user({ type: "media", ...media })] }),
         ).pipe(Effect.flip)
         expect(error.message).toMatch(/does not support|does not match|valid base64/)
@@ -239,7 +238,7 @@ describe("Gemini route", () => {
 
   it.effect("rejects oversized image input", () =>
     Effect.gen(function* () {
-      const error = yield* compileRequest(
+      const error = yield* LLMClient.prepare(
         LLM.request({
           model,
           messages: [
@@ -257,7 +256,7 @@ describe("Gemini route", () => {
 
   it.effect("keeps tools and sends function calling mode NONE", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           id: "req_tool_choice_none",
           model,
@@ -277,7 +276,7 @@ describe("Gemini route", () => {
 
   it.effect("sanitizes integer enums, dangling required, untyped arrays, and scalar object keys", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           id: "req_schema_patch",
           model,
@@ -458,7 +457,7 @@ describe("Gemini route", () => {
         response.events.findIndex((event) => event.type === "tool-call"),
       )
 
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<Gemini.GeminiBody>(
         LLM.request({
           model,
           messages: [
@@ -692,7 +691,7 @@ describe("Gemini route", () => {
 
   it.effect("rejects unsupported assistant media content", () =>
     Effect.gen(function* () {
-      const error = yield* compileRequest(
+      const error = yield* LLMClient.prepare(
         LLM.request({
           id: "req_media",
           model,

packages/ai/test/provider/google-vertex.test.ts

@@ -4,7 +4,6 @@ import { HttpClientRequest } from "effect/unstable/http"
 import { LLM } from "../../src"
 import { GoogleVertex, GoogleVertexChat, GoogleVertexMessages, GoogleVertexResponses } from "../../src/providers"
 import { LLMClient } from "../../src/route"
-import { compileRequest } from "../../src/route/client"
 import { it } from "../lib/effect"
 import { dynamicResponse } from "../lib/http"
 import { deltaChunk, finishChunk } from "../lib/openai-chunks"
@@ -183,7 +182,7 @@ describe("Google Vertex providers", () => {
 
   it.effect("protects the Vertex Messages API version from body overlays", () =>
     Effect.gen(function* () {
-      const error = yield* compileRequest(
+      const error = yield* LLMClient.prepare(
         LLM.request({
           model: GoogleVertexMessages.configure({
             accessToken: "vertex-token",

packages/ai/test/provider/openai-chat-reasoning.recorded.test.ts

@@ -5,7 +5,6 @@ import { OpenAIChat } from "../../src/protocols/openai-chat"
 import * as OpenAICompatible from "../../src/providers/openai-compatible"
 import * as OpenRouter from "../../src/providers/openrouter"
 import { LLMClient } from "../../src/route"
-import { compileRequest } from "../../src/route/client"
 import { recordedTests } from "../recorded-test"
 import { expectWeatherToolLoop, goldenWeatherToolLoopRequest, runWeatherToolLoop } from "../recorded-scenarios"
 
@@ -85,7 +84,9 @@ for (const item of cases) {
             ),
           ).toBe(true)
 
-          const replay = yield* compileRequest(LLM.request({ model: item.model, messages: [response.message] }))
+          const replay = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
+            LLM.request({ model: item.model, messages: [response.message] }),
+          )
           expect(replay.body.messages).toMatchObject([
             { role: "assistant", content: response.text, reasoning: response.reasoning },
           ])

packages/ai/test/provider/openai-chat.test.ts

@@ -18,7 +18,6 @@ import * as OpenAI from "../../src/providers/openai"
 import * as OpenAIChat from "../../src/protocols/openai-chat"
 import { ProviderShared } from "../../src/protocols/shared"
 import { Auth, LLMClient } from "../../src/route"
-import { compileRequest } from "../../src/route/client"
 import { it } from "../lib/effect"
 import { dynamicResponse, fixedResponse, truncatedStream } from "../lib/http"
 import { deltaChunk, usageChunk } from "../lib/openai-chunks"
@@ -43,7 +42,11 @@ const request = LLM.request({
 describe("OpenAI Chat route", () => {
   it.effect("prepares OpenAI Chat payload", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(request)
+      // Pass the OpenAIChat payload type so `prepared.body` is statically
+      // typed to the route's native shape — the assertions below read field
+      // names without `unknown` casts.
+      const prepared = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(request)
+      const _typed: { readonly model: string; readonly stream: true } = prepared.body
 
       expect(prepared.body).toEqual({
         model: "gpt-4o-mini",
@@ -61,7 +64,7 @@ describe("OpenAI Chat route", () => {
 
   it.effect("lowers chronological system updates to escaped user wrappers in order", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
         LLM.request({
           model,
           messages: [
@@ -84,7 +87,7 @@ describe("OpenAI Chat route", () => {
 
   it.effect("replays canonical reasoning as OpenAI-compatible reasoning_content", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
         LLM.request({
           model,
           messages: [
@@ -102,7 +105,7 @@ describe("OpenAI Chat route", () => {
 
   it.effect("writes reasoning to a configured custom field on every assistant message", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
         LLM.request({
           model: Model.update(model, { compatibility: { reasoningField: "vendor_reasoning" } }),
           messages: [
@@ -128,7 +131,7 @@ describe("OpenAI Chat route", () => {
 
   it.effect("rejects reasoning fields that conflict with assistant message fields", () =>
     Effect.gen(function* () {
-      const error = yield* compileRequest(
+      const error = yield* LLMClient.prepare(
         LLM.request({
           model: Model.update(model, { compatibility: { reasoningField: "content" } }),
           messages: [Message.assistant([{ type: "reasoning", text: "thinking" }])],
@@ -141,7 +144,7 @@ describe("OpenAI Chat route", () => {
 
   it.effect("maps OpenAI provider options to Chat options", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
         LLM.request({
           model: OpenAI.configure({ baseURL: "https://api.openai.test/v1/", apiKey: "test" }).chat("gpt-4o-mini"),
           prompt: "think",
@@ -156,7 +159,7 @@ describe("OpenAI Chat route", () => {
 
   it.effect("passes through custom OpenAI-compatible reasoning effort strings", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
         LLM.request({
           model,
           prompt: "think",
@@ -250,7 +253,7 @@ describe("OpenAI Chat route", () => {
 
   it.effect("prepares assistant tool-call and tool-result messages", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           id: "req_tool_result",
           model,
@@ -288,7 +291,7 @@ describe("OpenAI Chat route", () => {
   it.effect("preserves structured tool errors for the model", () =>
     Effect.gen(function* () {
       const error = { error: { type: "unknown", message: "Tool execution interrupted" } }
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
         LLM.request({
           model,
           messages: [
@@ -308,7 +311,7 @@ describe("OpenAI Chat route", () => {
 
   it.effect("continues image tool results as vision input without base64 text", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
         LLM.request({
           model,
           messages: [
@@ -352,7 +355,7 @@ describe("OpenAI Chat route", () => {
 
   it.effect("orders parallel tool responses before one aggregated vision message", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
         LLM.request({
           model,
           messages: [
@@ -402,7 +405,7 @@ describe("OpenAI Chat route", () => {
 
   it.effect("aggregates consecutive tool images with a following system update", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
         LLM.request({
           model,
           messages: [
@@ -443,7 +446,7 @@ describe("OpenAI Chat route", () => {
 
   it.effect("appends system updates without replacing multipart user content", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
         LLM.request({
           model,
           messages: [
@@ -471,7 +474,7 @@ describe("OpenAI Chat route", () => {
   ] as const)
     it.effect(`rejects ${name}`, () =>
       Effect.gen(function* () {
-        const error = yield* compileRequest(
+        const error = yield* LLMClient.prepare(
           LLM.request({ model, messages: [Message.user({ type: "media", ...media })] }),
         ).pipe(Effect.flip)
         expect(error.message).toMatch(/does not support|does not match|valid base64/)
@@ -480,7 +483,7 @@ describe("OpenAI Chat route", () => {
 
   it.effect("rejects oversized image input", () =>
     Effect.gen(function* () {
-      const error = yield* compileRequest(
+      const error = yield* LLMClient.prepare(
         LLM.request({
           model,
           messages: [
@@ -498,7 +501,7 @@ describe("OpenAI Chat route", () => {
 
   it.effect("prepares raw and data URL image media as vision input", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
         LLM.request({
           id: "req_media",
           model,
@@ -525,7 +528,7 @@ describe("OpenAI Chat route", () => {
 
   it.effect("lowers reasoning-only assistant history", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
         LLM.request({
           id: "req_reasoning",
           model,
@@ -616,7 +619,9 @@ describe("OpenAI Chat route", () => {
           openai: { reasoningField: field },
         })
 
-        const replay = yield* compileRequest(LLM.request({ model, messages: [response.message] }))
+        const replay = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
+          LLM.request({ model, messages: [response.message] }),
+        )
         expect(replay.body.messages).toEqual([{ role: "assistant", content: "Hello", [field]: "thinking" }])
       }
     }),
@@ -642,7 +647,9 @@ describe("OpenAI Chat route", () => {
         openai: { reasoningField: "vendor_reasoning" },
       })
 
-      const replay = yield* compileRequest(LLM.request({ model: custom, messages: [response.message] }))
+      const replay = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
+        LLM.request({ model: custom, messages: [response.message] }),
+      )
       expect(replay.body.messages).toEqual([{ role: "assistant", content: "Hello", vendor_reasoning: "thinking" }])
     }),
   )
@@ -685,7 +692,9 @@ describe("OpenAI Chat route", () => {
         openai: { reasoningField: "reasoning", reasoningDetails: details },
       })
 
-      const replay = yield* compileRequest(LLM.request({ model, messages: [response.message] }))
+      const replay = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
+        LLM.request({ model, messages: [response.message] }),
+      )
       expect(replay.body.messages).toEqual([
         {
           role: "assistant",
@@ -728,7 +737,9 @@ describe("OpenAI Chat route", () => {
         openai: { reasoningDetails: details },
       })
 
-      const replay = yield* compileRequest(LLM.request({ model, messages: [response.message] }))
+      const replay = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
+        LLM.request({ model, messages: [response.message] }),
+      )
       expect(replay.body.messages).toEqual([{ role: "assistant", content: "Hello", reasoning_details: details }])
     }),
   )
@@ -753,7 +764,9 @@ describe("OpenAI Chat route", () => {
         openai: { reasoningField: "reasoning", reasoningDetails: details },
       })
 
-      const replay = yield* compileRequest(LLM.request({ model, messages: [response.message] }))
+      const replay = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
+        LLM.request({ model, messages: [response.message] }),
+      )
       expect(replay.body.messages).toEqual([
         { role: "assistant", content: "Hello", reasoning: "thinking", reasoning_details: details },
       ])
@@ -826,7 +839,9 @@ describe("OpenAI Chat route", () => {
         openai: { reasoningDetails: [] },
       })
 
-      const replay = yield* compileRequest(LLM.request({ model, messages: [response.message] }))
+      const replay = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
+        LLM.request({ model, messages: [response.message] }),
+      )
       expect(replay.body.messages).toEqual([{ role: "assistant", content: "Hello", reasoning_details: [] }])
     }),
   )
@@ -874,7 +889,9 @@ describe("OpenAI Chat route", () => {
         response.events.findIndex(LLMEvent.is.textStart),
       )
 
-      const replay = yield* compileRequest(LLM.request({ model, messages: [response.message] }))
+      const replay = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
+        LLM.request({ model, messages: [response.message] }),
+      )
       expect(replay.body.messages).toEqual([
         { role: "assistant", content: "Hello", reasoning: "thinking", reasoning_details: merged },
       ])
@@ -901,7 +918,9 @@ describe("OpenAI Chat route", () => {
       expect(response.events.filter(LLMEvent.is.reasoningStart)).toHaveLength(1)
       expect(response.events.filter(LLMEvent.is.reasoningEnd)).toHaveLength(1)
 
-      const replay = yield* compileRequest(LLM.request({ model, messages: [response.message] }))
+      const replay = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
+        LLM.request({ model, messages: [response.message] }),
+      )
       expect(replay.body.messages).toEqual([{ role: "assistant", content: null, reasoning_details: details }])
     }),
   )
@@ -931,7 +950,7 @@ describe("OpenAI Chat route", () => {
     Effect.gen(function* () {
       const first = { type: "reasoning.text", text: "first", signature: "signed-0", index: 0 }
       const second = { type: "reasoning.text", text: "second", signature: "signed-1", index: 1 }
-      const replay = yield* compileRequest(
+      const replay = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
         LLM.request({
           model,
           messages: [
@@ -960,7 +979,7 @@ describe("OpenAI Chat route", () => {
   it.effect("retains scalar replay for mixed structured reasoning parts", () =>
     Effect.gen(function* () {
       const detail = { type: "reasoning.encrypted", data: "opaque", index: 0 }
-      const replay = yield* compileRequest(
+      const replay = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
         LLM.request({
           model,
           messages: [
@@ -985,7 +1004,7 @@ describe("OpenAI Chat route", () => {
   it.effect("replays native scalar reasoning alongside native details", () =>
     Effect.gen(function* () {
       const details = [{ type: "reasoning.encrypted", data: "opaque", index: 0 }]
-      const replay = yield* compileRequest(
+      const replay = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
         LLM.request({
           model,
           messages: [

packages/ai/test/provider/openai-compatible-chat.test.ts

@@ -3,7 +3,6 @@ import { Effect, Schema } from "effect"
 import { HttpClientRequest } from "effect/unstable/http"
 import { LLM, LLMRequest, Message, ToolCallPart, ToolChoice, ToolDefinition } from "../../src"
 import { Auth, LLMClient } from "../../src/route"
-import { compileRequest } from "../../src/route/client"
 import * as OpenAICompatible from "../../src/providers/openai-compatible"
 import * as OpenAICompatibleChat from "../../src/protocols/openai-compatible-chat"
 import { it } from "../lib/effect"
@@ -53,7 +52,7 @@ const providerFamilies = [
 describe("OpenAI-compatible Chat route", () => {
   it.effect("prepares generic Chat target", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLMRequest.update(request, {
           tools: [ToolDefinition.make({ name: "lookup", description: "Lookup data", inputSchema: { type: "object" } })],
           toolChoice: ToolChoice.make({ type: "required" }),
@@ -128,7 +127,7 @@ describe("OpenAI-compatible Chat route", () => {
 
   it.effect("matches AI SDK compatible basic request body fixture", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(request)
+      const prepared = yield* LLMClient.prepare(request)
 
       expect(prepared.body).toEqual({
         model: "deepseek-chat",
@@ -146,7 +145,7 @@ describe("OpenAI-compatible Chat route", () => {
 
   it.effect("matches AI SDK compatible tool request body fixture", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           id: "req_tool_parity",
           model,

packages/ai/test/provider/openai-compatible-responses.test.ts

@@ -7,7 +7,6 @@ import { OpenResponses } from "../../src/protocols/open-responses"
 import { OpenAICompatibleResponses } from "../../src/protocols/openai-compatible-responses"
 import { OpenAIResponses } from "../../src/protocols/openai-responses"
 import { LLMClient } from "../../src/route"
-import { compileRequest } from "../../src/route/client"
 import { it } from "../lib/effect"
 import { fixedResponse } from "../lib/http"
 import { sseEvents } from "../lib/sse"
@@ -24,7 +23,7 @@ describe("Open Responses-compatible route", () => {
         baseURL: "https://responses.example.test/v1",
         provider: "example",
       }).model("example-model")
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           model,
           system: "You are concise.",
@@ -62,7 +61,7 @@ describe("Open Responses-compatible route", () => {
         apiKey: "test-key",
         baseURL: "https://responses.example.test/v1",
       }).model("example-model")
-      const error = yield* compileRequest(
+      const error = yield* LLMClient.prepare(
         LLM.request({ model, prompt: "Draw.", tools: [OpenAI.imageGeneration()] }),
       ).pipe(Effect.flip)
 
@@ -77,7 +76,7 @@ describe("Open Responses-compatible route", () => {
         apiKey: "test-key",
         baseURL: "https://responses.example.test/v1",
       }).model("example-model")
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           model,
           messages: [
@@ -103,7 +102,7 @@ describe("Open Responses-compatible route", () => {
         baseURL: "https://responses.example.test/v1",
         providerOptions: { openresponses: { reasoningEffort: "low", store: true } },
       }).model("example-model")
-      const prepared = yield* compileRequest(LLM.request({ model, prompt: "Think." }))
+      const prepared = yield* LLMClient.prepare(LLM.request({ model, prompt: "Think." }))
 
       expect(prepared.body).toMatchObject({
         reasoning: { effort: "low" },

packages/ai/test/provider/openai-responses.test.ts

@@ -14,7 +14,6 @@ import {
   Usage,
 } from "../../src"
 import { Auth, LLMClient, RequestExecutor, WebSocketExecutor } from "../../src/route"
-import { compileRequest } from "../../src/route/client"
 import * as Azure from "../../src/providers/azure"
 import * as OpenAI from "../../src/providers/openai"
 import * as XAI from "../../src/providers/xai"
@@ -57,7 +56,7 @@ const expectToolOutput = (body: OpenAIResponses.OpenAIResponsesBody): OpenAITool
 describe("OpenAI Responses route", () => {
   it.effect("prepares OpenAI Responses target", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(request)
+      const prepared = yield* LLMClient.prepare(request)
 
       expect(prepared.body).toEqual({
         model: "gpt-4.1-mini",
@@ -75,7 +74,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("lowers the hosted OpenAI image generation tool", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLM.request({
           model,
           prompt: "Show me a rooftop garden.",
@@ -93,7 +92,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("rejects invalid hosted image generation options locally", () =>
     Effect.gen(function* () {
-      const error = yield* compileRequest(
+      const error = yield* LLMClient.prepare(
         LLM.request({
           model,
           prompt: "Show me a rooftop garden.",
@@ -110,7 +109,7 @@ describe("OpenAI Responses route", () => {
     Effect.gen(function* () {
       const input = LLMRequest.update(request, { providerOptions: { openai: { serviceTier: "priority" } } })
       expect(input.providerOptions).toEqual({ openai: { serviceTier: "priority" } })
-      const prepared = yield* compileRequest(input)
+      const prepared = yield* LLMClient.prepare(input)
 
       expect(prepared.body).toMatchObject({ service_tier: "priority" })
       expect(prepared.body).not.toHaveProperty("serviceTier")
@@ -119,7 +118,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("passes through custom OpenAI reasoning effort strings", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLMRequest.update(request, { providerOptions: { openai: { reasoningEffort: "experimental" } } }),
       )
 
@@ -129,7 +128,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("omits unsupported semantic service tiers", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLMRequest.update(request, { providerOptions: { openai: { serviceTier: "unsupported" } } }),
       )
 
@@ -139,7 +138,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("flattens top-level object unions in function schemas", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLMRequest.update(request, {
           tools: [
             ToolDefinition.make({
@@ -192,7 +191,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("lowers chronological system updates to escaped user wrappers in order", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLM.request({
           model,
           messages: [
@@ -218,7 +217,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("prepares OpenAI Responses WebSocket target", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLMRequest.update(request, {
           model: OpenAIResponses.webSocketRoute
             .with({ endpoint: { baseURL: "https://api.openai.test/v1/" }, auth: Auth.bearer("test") })
@@ -396,7 +395,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("prepares function call and function output input items", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           id: "req_tool_result",
           model,
@@ -433,7 +432,7 @@ describe("OpenAI Responses route", () => {
         content: [],
         structured: {},
       }
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLM.request({
           model,
           messages: [
@@ -454,7 +453,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("keeps primitive tool errors as plain text", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLM.request({
           model,
           messages: [
@@ -470,7 +469,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("keeps non-JSON tool errors as plain text", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLM.request({
           model,
           messages: [
@@ -488,7 +487,7 @@ describe("OpenAI Responses route", () => {
   // image data is not JSON-stringified into `function_call_output.output`.
   it.effect("lowers image tool-result content as structured input_image items", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLM.request({
           id: "req_tool_result_image",
           model,
@@ -517,7 +516,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("lowers single-image tool-result content as structured input_image array", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLM.request({
           id: "req_tool_result_image_only",
           model,
@@ -541,7 +540,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("lowers PDF tool-result content as structured input_file array", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLM.request({
           id: "req_tool_result_pdf",
           model,
@@ -576,7 +575,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("uses xAI inline file encoding for PDF tool results", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLM.request({
           model: xaiModel,
           messages: [
@@ -611,7 +610,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("rejects unsupported media in tool-result content with a clear error", () =>
     Effect.gen(function* () {
-      const error = yield* compileRequest(
+      const error = yield* LLMClient.prepare(
         LLM.request({
           id: "req_tool_result_unsupported_media",
           model,
@@ -634,7 +633,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("prepares the composed native continuation request", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         continuationRequest({
           id: "req_native_continuation_openai",
           model,
@@ -676,7 +675,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("maps OpenAI provider options to Responses options", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLM.request({
           model: OpenAI.configure({ baseURL: "https://api.openai.test/v1/", apiKey: "test" }).model("gpt-5.2"),
           prompt: "think",
@@ -701,7 +700,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("accepts the full ResponseIncludable union", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLM.request({
           model,
           prompt: "hi",
@@ -723,7 +722,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("filters unknown includable values out of the include array", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLM.request({
           model,
           prompt: "hi",
@@ -740,7 +739,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("treats an explicit empty include as no include at all", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLM.request({ model, prompt: "hi", providerOptions: { openai: { include: [] } } }),
       )
 
@@ -750,7 +749,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("treats an all-invalid include as no include at all", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLM.request({ model, prompt: "hi", providerOptions: { openai: { include: ["bogus.thing"] } } }),
       )
 
@@ -760,7 +759,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("omits include when no include is set", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLM.request({ model, prompt: "hi", providerOptions: { openai: { store: false } } }),
       )
 
@@ -774,7 +773,7 @@ describe("OpenAI Responses route", () => {
       // reasoningSummary: "auto" by default. Without `include`, a follow-up
       // turn cannot replay reasoning state, so the facade also opts into
       // `reasoning.encrypted_content` automatically.
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLM.request({
           model: OpenAI.configure({ baseURL: "https://api.openai.test/v1/", apiKey: "test" }).responses("gpt-5.2"),
           prompt: "hi",
@@ -789,7 +788,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("lets callers opt out of the GPT-5 default include", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLM.request({
           model: OpenAI.configure({ baseURL: "https://api.openai.test/v1/", apiKey: "test" }).responses("gpt-5.2"),
           prompt: "hi",
@@ -803,7 +802,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("request OpenAI provider options override route defaults", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLM.request({
           model: OpenAI.configure({
             baseURL: "https://api.openai.test/v1/",
@@ -935,7 +934,9 @@ describe("OpenAI Responses route", () => {
         },
       ])
 
-      const prepared = yield* compileRequest(LLM.request({ model, messages: [response.message] }))
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
+        LLM.request({ model, messages: [response.message] }),
+      )
       expect(prepared.body.input).toEqual([
         {
           role: "assistant",
@@ -1269,7 +1270,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("preserves assistant content order around reasoning items", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLM.request({
           id: "req_reasoning_order",
           model,
@@ -1307,7 +1308,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("references stored reasoning items by id", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLM.request({
           model,
           messages: [
@@ -1329,7 +1330,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("references stored provider-executed hosted tool results by id", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLM.request({
           model,
           messages: [
@@ -1366,7 +1367,7 @@ describe("OpenAI Responses route", () => {
   it.effect("continues stateless hosted image generation with the generated image", () =>
     Effect.gen(function* () {
       const imageTool = OpenAI.imageGeneration({ action: "edit" })
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLM.request({
           model,
           messages: [
@@ -1407,7 +1408,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("joins streamed summary blocks into one continuation reasoning item", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLM.request({
           id: "req_multi_summary_continuation",
           model,
@@ -1444,7 +1445,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("skips non-persisted reasoning ids without encrypted state", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           id: "req_reasoning_without_encrypted_state",
           model,
@@ -1761,7 +1762,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("lowers user image and PDF content", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLM.request({
           id: "req_media",
           model,
@@ -1792,7 +1793,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("uses xAI inline file encoding for user PDFs", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIResponses.OpenAIResponsesBody>(
         LLM.request({
           model: xaiModel,
           messages: [
@@ -1824,7 +1825,7 @@ describe("OpenAI Responses route", () => {
 
   it.effect("rejects unsupported user media content", () =>
     Effect.gen(function* () {
-      const error = yield* compileRequest(
+      const error = yield* LLMClient.prepare(
         LLM.request({
           id: "req_media",
           model,

packages/ai/test/provider/openrouter.test.ts

@@ -2,7 +2,6 @@ import { describe, expect } from "bun:test"
 import { Effect } from "effect"
 import { LLM, Message } from "../../src"
 import { LLMClient } from "../../src/route"
-import { compileRequest } from "../../src/route/client"
 import * as OpenRouter from "../../src/providers/openrouter"
 import { it } from "../lib/effect"
 import { fixedResponse } from "../lib/http"
@@ -20,7 +19,7 @@ describe("OpenRouter", () => {
       })
       expect(model.route.endpoint.baseURL).toBe("https://openrouter.ai/api/v1")
 
-      const prepared = yield* compileRequest(LLM.request({ model, prompt: "Say hello." }))
+      const prepared = yield* LLMClient.prepare(LLM.request({ model, prompt: "Say hello." }))
 
       expect(prepared.route).toBe("openrouter")
       expect(prepared.body).toMatchObject({
@@ -33,7 +32,7 @@ describe("OpenRouter", () => {
 
   it.effect("applies OpenRouter payload options from the model helper", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare(
         LLM.request({
           model: OpenRouter.configure({
             apiKey: "test-key",
@@ -101,7 +100,7 @@ describe("OpenRouter", () => {
         { type: "reasoning.text", signature: "signed", format: "anthropic-claude-v1", index: 0 },
         { type: "reasoning.encrypted", data: "opaque", format: "openai-responses-v1", index: 1 },
       ]
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenRouter.OpenRouterBody>(
         LLM.request({
           model: OpenRouter.configure({ apiKey: "test-key" }).model("anthropic/claude-sonnet-4.6"),
           messages: [
@@ -134,7 +133,7 @@ describe("OpenRouter", () => {
         { type: "reasoning.encrypted", id: "state", data: "opaque" },
         { type: "reasoning.encrypted", id: "state", data: "opaque" },
       ]
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenRouter.OpenRouterBody>(
         LLM.request({
           model: OpenRouter.configure({ apiKey: "test-key" }).model("anthropic/claude-sonnet-4.6"),
           messages: [
@@ -159,7 +158,7 @@ describe("OpenRouter", () => {
         { type: "reasoning.text", id: "first", index: 0, text: "A", opaque: "first" },
         { type: "reasoning.text", id: "second", index: 1, text: "B", opaque: "second" },
       ]
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenRouter.OpenRouterBody>(
         LLM.request({
           model: OpenRouter.configure({ apiKey: "test-key" }).model("anthropic/claude-sonnet-4.6"),
           messages: [
@@ -180,7 +179,7 @@ describe("OpenRouter", () => {
 
   it.effect("omits scalar reasoning without continuation details", () =>
     Effect.gen(function* () {
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenRouter.OpenRouterBody>(
         LLM.request({
           model: OpenRouter.configure({ apiKey: "test-key" }).model("anthropic/claude-sonnet-4.6"),
           messages: [Message.assistant({ type: "reasoning", text: "Thinking" })],

packages/ai/test/tool-schema-projection.test.ts

@@ -3,8 +3,7 @@ import { Effect } from "effect"
 import { LLM } from "../src"
 import { OpenAIChat } from "../src/protocols"
 import { ToolSchemaProjection } from "../src/protocols/utils/tool-schema"
-import { Auth } from "../src/route"
-import { compileRequest } from "../src/route/client"
+import { Auth, LLMClient } from "../src/route"
 import { it } from "./lib/effect"
 
 describe("tool schema projections", () => {
@@ -80,7 +79,7 @@ describe("tool schema projections", () => {
       const model = OpenAIChat.route
         .with({ endpoint: { baseURL: "https://api.openai.test/v1/" }, auth: Auth.bearer("test") })
         .model({ id: "kimi-k2", compatibility: { toolSchema: "moonshot" } })
-      const prepared = yield* compileRequest(
+      const prepared = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
         LLM.request({
           model,
           prompt: "Use the tool.",

packages/app/src/components/dialog-fork.tsx

@@ -69,7 +69,7 @@ export const DialogFork: Component = () => {
     const dir = base64Encode(sdk().directory)
 
     sdk()
-      .api.session.fork({ sessionID, boundary: { type: "before", messageID: item.id } })
+      .api.session.fork({ sessionID, messageID: item.id })
       .then((forked) => {
         dialog.close()
         prompt.set(restored, undefined, { dir, id: forked.id })

packages/app/src/components/dialog-select-server.tsx

@@ -6,22 +6,17 @@ import { Icon } from "@opencode-ai/ui/icon"
 import { IconButton } from "@opencode-ai/ui/icon-button"
 import { List } from "@opencode-ai/ui/list"
 import { TextField } from "@opencode-ai/ui/text-field"
-import { useMutation } from "@tanstack/solid-query"
-import { showToast } from "@/utils/toast"
-import { useNavigate } from "@solidjs/router"
-import { createEffect, createMemo, createResource, Show } from "solid-js"
-import { createStore } from "solid-js/store"
+import { Show } from "solid-js"
 import { ServerHealthIndicator, ServerRow } from "@/components/server/server-row"
-import { useGlobal } from "@/context/global"
 import { useLanguage } from "@/context/language"
-import { usePlatform } from "@/context/platform"
-import { normalizeServerUrl, ServerConnection, useServer } from "@/context/server"
-import { detectServerProtocol } from "@/utils/server-protocol"
-import { type ServerHealth, useCheckServerHealth } from "@/utils/server-health"
+import { ServerConnection } from "@/context/server"
 import { useSettings } from "@/context/settings"
-import { useTabs } from "@/context/tabs"
-
-const DEFAULT_USERNAME = "opencode"
+import {
+  type ServerDomainController,
+  type ServerFormController,
+  useServerDomainController,
+  useServerFormController,
+} from "@/components/server/server-management-controller"
 
 interface ServerFormProps {
   value: string
@@ -40,76 +35,6 @@ interface ServerFormProps {
   onBack: () => void
 }
 
-function showRequestError(language: ReturnType<typeof useLanguage>, err: unknown) {
-  showToast({
-    variant: "error",
-    title: language.t("common.requestFailed"),
-    description: err instanceof Error ? err.message : String(err),
-  })
-}
-
-function useDefaultServer() {
-  const language = useLanguage()
-  const platform = usePlatform()
-  const [defaultKey, defaultUrlActions] = createResource(
-    async () => {
-      try {
-        const key = await platform.getDefaultServer?.()
-        if (!key) return null
-        return key
-      } catch (err) {
-        showRequestError(language, err)
-        return null
-      }
-    },
-    { initialValue: null },
-  )
-
-  const canDefault = createMemo(() => !!platform.getDefaultServer && !!platform.setDefaultServer)
-  const setDefault = async (key: ServerConnection.Key | null) => {
-    try {
-      await platform.setDefaultServer?.(key)
-      defaultUrlActions.mutate(key)
-    } catch (err) {
-      showRequestError(language, err)
-    }
-  }
-
-  return { defaultKey: () => defaultKey.latest, canDefault, setDefault }
-}
-
-function useServerPreview() {
-  const checkServerHealth = useCheckServerHealth()
-
-  const looksComplete = (value: string) => {
-    const normalized = normalizeServerUrl(value)
-    if (!normalized) return false
-    const host = normalized.replace(/^https?:\/\//, "").split("/")[0]
-    if (!host) return false
-    if (host.includes("localhost") || host.startsWith("127.0.0.1")) return true
-    return host.includes(".") || host.includes(":")
-  }
-
-  const previewStatus = async (
-    value: string,
-    username: string,
-    password: string,
-    setStatus: (value: boolean | undefined) => void,
-  ) => {
-    setStatus(undefined)
-    if (!looksComplete(value)) return
-    const normalized = normalizeServerUrl(value)
-    if (!normalized) return
-    const http: ServerConnection.HttpBase = { url: normalized }
-    if (username) http.username = username
-    if (password) http.password = password
-    const result = await checkServerHealth(http)
-    setStatus(result.healthy)
-  }
-
-  return { previewStatus }
-}
-
 function ServerForm(props: ServerFormProps) {
   const language = useLanguage()
   const keyDown = (event: KeyboardEvent) => {
@@ -177,401 +102,40 @@ function ServerForm(props: ServerFormProps) {
 
 export function DialogSelectServer() {
   const dialog = useDialog()
-  const controller = useServerManagementController({ onSelect: dialog.close })
+  const language = useLanguage()
+  const domain = useServerDomainController({ onSelect: () => dialog.close() })
+  const form = useServerFormController({ onSelect: () => dialog.close() })
+  const title = () => {
+    if (!form.state.open()) return language.t("dialog.server.title")
+    return (
+      <div class="flex items-center gap-2 -ml-2">
+        <IconButton icon="arrow-left" variant="ghost" onClick={form.reset} aria-label={language.t("common.goBack")} />
+        <span>
+          {form.state.adding() ? language.t("dialog.server.add.title") : language.t("dialog.server.edit.title")}
+        </span>
+      </div>
+    )
+  }
 
   return (
-    <Dialog title={controller.formTitle()}>
+    <Dialog title={title()}>
       <div class="flex flex-1 min-h-0 flex-col px-5">
-        <Show when={controller.isFormMode()} fallback={<ServerConnectionList controller={controller} />}>
-          <ServerConnectionForm controller={controller} />
+        <Show
+          when={form.state.open()}
+          fallback={<ServerConnectionList domain={domain} onAdd={form.start.add} onEdit={form.start.edit} />}
+        >
+          <ServerConnectionForm form={form} />
         </Show>
       </div>
     </Dialog>
   )
 }
 
-export function useServerManagementController(options: { onSelect?: () => void; navigateOnAdd?: boolean } = {}) {
-  const navigate = useNavigate()
-  const server = useServer()
-  const tabs = useTabs()
-  const global = useGlobal()
-  const platform = usePlatform()
-  const language = useLanguage()
-  const { defaultKey, canDefault, setDefault } = useDefaultServer()
-  const { previewStatus } = useServerPreview()
-  const checkServerHealth = useCheckServerHealth()
-  const [store, setStore] = createStore({
-    addServer: {
-      url: "",
-      name: "",
-      username: DEFAULT_USERNAME,
-      password: "",
-      error: "",
-      showForm: false,
-      status: undefined as boolean | undefined,
-    },
-    editServer: {
-      id: undefined as string | undefined,
-      value: "",
-      name: "",
-      username: "",
-      password: "",
-      error: "",
-      status: undefined as boolean | undefined,
-    },
-  })
-
-  const resetAdd = () => {
-    setStore("addServer", {
-      url: "",
-      name: "",
-      username: DEFAULT_USERNAME,
-      password: "",
-      error: "",
-      showForm: false,
-      status: undefined,
-    })
-  }
-  const resetEdit = () => {
-    setStore("editServer", {
-      id: undefined,
-      value: "",
-      name: "",
-      username: "",
-      password: "",
-      error: "",
-      status: undefined,
-    })
-  }
-
-  const addMutation = useMutation(() => ({
-    mutationFn: async (value: string) => {
-      const normalized = normalizeServerUrl(value)
-      if (!normalized) {
-        resetAdd()
-        return
-      }
-
-      const conn: ServerConnection.Http = {
-        type: "http",
-        http: { url: normalized },
-      }
-      if (store.addServer.name.trim()) conn.displayName = store.addServer.name.trim()
-      if (store.addServer.password) conn.http.password = store.addServer.password
-      if (store.addServer.password && store.addServer.username) conn.http.username = store.addServer.username
-      const result = await checkServerHealth(conn.http)
-      if (!result.healthy) {
-        setStore("addServer", { error: language.t("dialog.server.add.error") })
-        return
-      }
-      if (
-        !settings.general.newLayoutDesigns() &&
-        (await detectServerProtocol(conn.http, platform.fetch ?? globalThis.fetch)) === "v2"
-      ) {
-        setStore("addServer", { error: language.t("dialog.server.add.error") })
-        return
-      }
-
-      resetAdd()
-      if (options.navigateOnAdd === false) {
-        server.add(conn)
-        options.onSelect?.()
-        return
-      }
-      await select(conn, true)
-    },
-  }))
-
-  const editMutation = useMutation(() => ({
-    mutationFn: async (input: { original: ServerConnection.Any; value: string }) => {
-      if (input.original.type !== "http") return
-      const normalized = normalizeServerUrl(input.value)
-      if (!normalized) {
-        resetEdit()
-        return
-      }
-
-      const name = store.editServer.name.trim() || undefined
-      const username = store.editServer.username || undefined
-      const password = store.editServer.password || undefined
-      const existingName = input.original.displayName
-      if (
-        normalized === input.original.http.url &&
-        name === existingName &&
-        username === input.original.http.username &&
-        password === input.original.http.password
-      ) {
-        resetEdit()
-        return
-      }
-
-      const conn: ServerConnection.Http = {
-        type: "http",
-        displayName: name,
-        http: { url: normalized, username, password },
-      }
-      const result = await checkServerHealth(conn.http)
-      if (!result.healthy) {
-        setStore("editServer", { error: language.t("dialog.server.add.error") })
-        return
-      }
-      if (
-        !settings.general.newLayoutDesigns() &&
-        (await detectServerProtocol(conn.http, platform.fetch ?? globalThis.fetch)) === "v2"
-      ) {
-        setStore("editServer", { error: language.t("dialog.server.add.error") })
-        return
-      }
-      if (normalized === input.original.http.url) {
-        server.add(conn)
-      } else {
-        replaceServer(input.original, conn)
-      }
-
-      resetEdit()
-    },
-  }))
-
-  const replaceServer = (original: ServerConnection.Http, next: ServerConnection.Http) => {
-    const originalKey = ServerConnection.key(original)
-    const active = server.key
-    tabs.removeServer(originalKey)
-    const newConn = server.add(next)
-    if (!newConn) return
-    const nextActive = active === originalKey ? ServerConnection.key(newConn) : active
-    if (nextActive) server.setActive(nextActive)
-    server.remove(originalKey)
-  }
-
-  const items = createMemo(() => {
-    const current = server.current
-    const list = server.list
-    if (!current) return list
-    if (!list.includes(current)) return [current, ...list]
-    return [current, ...list.filter((x) => x !== current)]
-  })
-
-  const settings = useSettings()
-  const current = createMemo<ServerConnection.Any | undefined>(() =>
-    settings.general.newLayoutDesigns()
-      ? undefined
-      : (items().find((x) => ServerConnection.key(x) === server.key) ?? items()[0]),
-  )
-
-  const sortedItems = createMemo(() => {
-    const raw = items()
-    const list = settings.general.newLayoutDesigns()
-      ? raw
-      : raw.filter((x) => global.ensureServerCtx(x).sdk.protocolKind() !== "v2")
-    if (!list.length) return list
-    const active = current()
-    const order = new Map(list.map((url, index) => [url, index] as const))
-    const rank = (value?: ServerHealth) => {
-      if (value?.healthy === true) return 0
-      if (value?.healthy === false) return 2
-      return 1
-    }
-    return list.slice().sort((a, b) => {
-      if (a === active) return -1
-      if (b === active) return 1
-      const diff =
-        rank(global.servers.health[ServerConnection.key(a)]) - rank(global.servers.health[ServerConnection.key(b)])
-      if (diff !== 0) return diff
-      return (order.get(a) ?? 0) - (order.get(b) ?? 0)
-    })
-  })
-
-  async function select(conn: ServerConnection.Any, persist?: boolean) {
-    if (!persist && global.servers.health[ServerConnection.key(conn)]?.healthy === false) return
-    options.onSelect?.()
-    if (persist && conn.type === "http") {
-      server.add(conn)
-      navigate("/")
-      return
-    }
-    navigate("/")
-    queueMicrotask(() => server.setActive(ServerConnection.key(conn)))
-  }
-
-  const handleAddChange = (value: string) => {
-    if (addMutation.isPending) return
-    setStore("addServer", { url: value, error: "" })
-    void previewStatus(value, store.addServer.username, store.addServer.password, (next) =>
-      setStore("addServer", { status: next }),
-    )
-  }
-
-  const handleAddNameChange = (value: string) => {
-    if (addMutation.isPending) return
-    setStore("addServer", { name: value, error: "" })
-  }
-
-  const handleAddUsernameChange = (value: string) => {
-    if (addMutation.isPending) return
-    setStore("addServer", { username: value, error: "" })
-    void previewStatus(store.addServer.url, value, store.addServer.password, (next) =>
-      setStore("addServer", { status: next }),
-    )
-  }
-
-  const handleAddPasswordChange = (value: string) => {
-    if (addMutation.isPending) return
-    setStore("addServer", { password: value, error: "" })
-    void previewStatus(store.addServer.url, store.addServer.username, value, (next) =>
-      setStore("addServer", { status: next }),
-    )
-  }
-
-  const handleEditChange = (value: string) => {
-    if (editMutation.isPending) return
-    setStore("editServer", { value, error: "" })
-    void previewStatus(value, store.editServer.username, store.editServer.password, (next) =>
-      setStore("editServer", { status: next }),
-    )
-  }
-
-  const handleEditNameChange = (value: string) => {
-    if (editMutation.isPending) return
-    setStore("editServer", { name: value, error: "" })
-  }
-
-  const handleEditUsernameChange = (value: string) => {
-    if (editMutation.isPending) return
-    setStore("editServer", { username: value, error: "" })
-    void previewStatus(store.editServer.value, value, store.editServer.password, (next) =>
-      setStore("editServer", { status: next }),
-    )
-  }
-
-  const handleEditPasswordChange = (value: string) => {
-    if (editMutation.isPending) return
-    setStore("editServer", { password: value, error: "" })
-    void previewStatus(store.editServer.value, store.editServer.username, value, (next) =>
-      setStore("editServer", { status: next }),
-    )
-  }
-
-  const mode = createMemo<"list" | "add" | "edit">(() => {
-    if (store.editServer.id) return "edit"
-    if (store.addServer.showForm) return "add"
-    return "list"
-  })
-
-  const editing = createMemo(() => {
-    if (!store.editServer.id) return
-    return items().find((x) => x.type === "http" && x.http.url === store.editServer.id)
-  })
-
-  const resetForm = () => {
-    resetAdd()
-    resetEdit()
-  }
-
-  const startAdd = () => {
-    resetEdit()
-    setStore("addServer", {
-      showForm: true,
-      url: "",
-      name: "",
-      username: DEFAULT_USERNAME,
-      password: "",
-      error: "",
-      status: undefined,
-    })
-  }
-
-  const startEdit = (conn: ServerConnection.Http) => {
-    resetAdd()
-    setStore("editServer", {
-      id: conn.http.url,
-      value: conn.http.url,
-      name: conn.displayName ?? "",
-      username: conn.http.username ?? "",
-      password: conn.http.password ?? "",
-      error: "",
-      status: global.servers.health[ServerConnection.key(conn)]?.healthy,
-    })
-  }
-
-  const submitForm = () => {
-    if (mode() === "add") {
-      if (addMutation.isPending) return
-      setStore("addServer", { error: "" })
-      addMutation.mutate(store.addServer.url)
-      return
-    }
-    const original = editing()
-    if (!original) return
-    if (editMutation.isPending) return
-    setStore("editServer", { error: "" })
-    editMutation.mutate({ original, value: store.editServer.value })
-  }
-
-  const isFormMode = createMemo(() => mode() !== "list")
-  const isAddMode = createMemo(() => mode() === "add")
-  const formBusy = createMemo(() => (isAddMode() ? addMutation.isPending : editMutation.isPending))
-
-  const formTitle = createMemo(() => {
-    if (!isFormMode()) return language.t("dialog.server.title")
-    return (
-      <div class="flex items-center gap-2 -ml-2">
-        <IconButton icon="arrow-left" variant="ghost" onClick={resetForm} aria-label={language.t("common.goBack")} />
-        <span>{isAddMode() ? language.t("dialog.server.add.title") : language.t("dialog.server.edit.title")}</span>
-      </div>
-    )
-  })
-
-  createEffect(() => {
-    if (!store.editServer.id) return
-    if (editing()) return
-    resetEdit()
-  })
-
-  async function handleRemove(key: ServerConnection.Key) {
-    try {
-      if (key.startsWith("wsl:")) await platform.wslServers?.removeServer(key)
-      tabs.removeServer(key)
-      server.remove(key)
-      if ((await platform.getDefaultServer?.()) === key) {
-        await setDefault(null)
-      }
-    } catch (err) {
-      showRequestError(language, err)
-    }
-  }
-
-  return {
-    defaultKey,
-    canDefault,
-    current,
-    sortedItems,
-    status: () => global.servers.health,
-    isFormMode,
-    isAddMode,
-    formTitle,
-    formBusy,
-    formValue: () => (isAddMode() ? store.addServer.url : store.editServer.value),
-    formName: () => (isAddMode() ? store.addServer.name : store.editServer.name),
-    formUsername: () => (isAddMode() ? store.addServer.username : store.editServer.username),
-    formPassword: () => (isAddMode() ? store.addServer.password : store.editServer.password),
-    formError: () => (isAddMode() ? store.addServer.error : store.editServer.error),
-    formStatus: () => (isAddMode() ? store.addServer.status : store.editServer.status),
-    select,
-    setDefault,
-    startAdd,
-    startEdit,
-    resetForm,
-    submitForm,
-    canRemove: server.canRemove,
-    handleRemove,
-    handleFormChange: () => (isAddMode() ? handleAddChange : handleEditChange),
-    handleFormNameChange: () => (isAddMode() ? handleAddNameChange : handleEditNameChange),
-    handleFormUsernameChange: () => (isAddMode() ? handleAddUsernameChange : handleEditUsernameChange),
-    handleFormPasswordChange: () => (isAddMode() ? handleAddPasswordChange : handleEditPasswordChange),
-  }
-}
-
-export function ServerConnectionList(props: { controller: ReturnType<typeof useServerManagementController> }) {
+export function ServerConnectionList(props: {
+  domain: ServerDomainController
+  onAdd: () => void
+  onEdit: (server: ServerConnection.Http) => void
+}) {
   const language = useLanguage()
   const settings = useSettings()
 
@@ -585,10 +149,10 @@ export function ServerConnectionList(props: { controller: ReturnType<typeof useS
         }}
         noInitialSelection
         emptyMessage={language.t("dialog.server.empty")}
-        items={props.controller.sortedItems}
+        items={props.domain.collection.items}
         key={(x) => x.http.url}
         onSelect={(x) => {
-          if (x && !settings.general.newLayoutDesigns()) void props.controller.select(x)
+          if (x && !settings.general.newLayoutDesigns()) void props.domain.selection.select(x)
         }}
         divider={true}
       >
@@ -597,15 +161,15 @@ export function ServerConnectionList(props: { controller: ReturnType<typeof useS
           return (
             <div class="flex items-center gap-3 min-w-0 flex-1 w-full group/item">
               <div class="flex flex-col h-full items-center w-5">
-                <ServerHealthIndicator health={props.controller.status()[key]} />
+                <ServerHealthIndicator health={props.domain.collection.health()[key]} />
               </div>
               <ServerRow
                 conn={i}
-                dimmed={props.controller.status()[key]?.healthy === false}
-                status={props.controller.status()[key]}
+                dimmed={props.domain.collection.health()[key]?.healthy === false}
+                status={props.domain.collection.health()[key]}
                 class="flex items-center gap-3 min-w-0 flex-1"
                 badge={
-                  <Show when={props.controller.defaultKey() === ServerConnection.key(i)}>
+                  <Show when={props.domain.defaults.key() === ServerConnection.key(i)}>
                     <span class="text-text-base bg-surface-base text-14-regular px-1.5 rounded-xs">
                       {language.t("dialog.server.status.default")}
                     </span>
@@ -614,7 +178,12 @@ export function ServerConnectionList(props: { controller: ReturnType<typeof useS
                 showCredentials
               />
               <div class="flex items-center justify-center gap-4 pl-4">
-                <Show when={props.controller.current() && ServerConnection.key(props.controller.current()!) === key}>
+                <Show
+                  when={
+                    props.domain.collection.current() &&
+                    ServerConnection.key(props.domain.collection.current()!) === key
+                  }
+                >
                   <Icon name="check" class="h-6" />
                 </Show>
 
@@ -633,27 +202,27 @@ export function ServerConnectionList(props: { controller: ReturnType<typeof useS
                         <DropdownMenu.Item
                           onSelect={() => {
                             if (i.type !== "http") return
-                            props.controller.startEdit(i)
+                            props.onEdit(i)
                           }}
                         >
                           <DropdownMenu.ItemLabel>{language.t("dialog.server.menu.edit")}</DropdownMenu.ItemLabel>
                         </DropdownMenu.Item>
-                        <Show when={props.controller.canDefault() && props.controller.defaultKey() !== key}>
-                          <DropdownMenu.Item onSelect={() => props.controller.setDefault(key)}>
+                        <Show when={props.domain.defaults.available() && props.domain.defaults.key() !== key}>
+                          <DropdownMenu.Item onSelect={() => props.domain.defaults.set(key)}>
                             <DropdownMenu.ItemLabel>{language.t("dialog.server.menu.default")}</DropdownMenu.ItemLabel>
                           </DropdownMenu.Item>
                         </Show>
-                        <Show when={props.controller.canDefault() && props.controller.defaultKey() === key}>
-                          <DropdownMenu.Item onSelect={() => props.controller.setDefault(null)}>
+                        <Show when={props.domain.defaults.available() && props.domain.defaults.key() === key}>
+                          <DropdownMenu.Item onSelect={() => props.domain.defaults.set(null)}>
                             <DropdownMenu.ItemLabel>
                               {language.t("dialog.server.menu.defaultRemove")}
                             </DropdownMenu.ItemLabel>
                           </DropdownMenu.Item>
                         </Show>
-                        <Show when={props.controller.canRemove(key)}>
+                        <Show when={props.domain.connection.canRemove(key)}>
                           <DropdownMenu.Separator />
                           <DropdownMenu.Item
-                            onSelect={() => props.controller.handleRemove(ServerConnection.key(i))}
+                            onSelect={() => props.domain.connection.remove(key)}
                             class="text-text-on-critical-base hover:bg-surface-critical-weak"
                           >
                             <DropdownMenu.ItemLabel>{language.t("dialog.server.menu.delete")}</DropdownMenu.ItemLabel>
@@ -674,7 +243,7 @@ export function ServerConnectionList(props: { controller: ReturnType<typeof useS
           variant="secondary"
           icon="plus-small"
           size="large"
-          onClick={props.controller.startAdd}
+          onClick={props.onAdd}
           class="py-1.5 pl-1.5 pr-3 flex items-center gap-1.5"
         >
           {language.t("dialog.server.add.button")}
@@ -684,38 +253,38 @@ export function ServerConnectionList(props: { controller: ReturnType<typeof useS
   )
 }
 
-export function ServerConnectionForm(props: { controller: ReturnType<typeof useServerManagementController> }) {
+export function ServerConnectionForm(props: { form: ServerFormController }) {
   const language = useLanguage()
 
   return (
     <div class="flex flex-1 min-h-0 flex-col gap-4">
       <ServerForm
-        value={props.controller.formValue()}
-        name={props.controller.formName()}
-        username={props.controller.formUsername()}
-        password={props.controller.formPassword()}
+        value={props.form.state.value()}
+        name={props.form.state.name()}
+        username={props.form.state.username()}
+        password={props.form.state.password()}
         placeholder={language.t("dialog.server.add.placeholder")}
-        busy={props.controller.formBusy()}
-        error={props.controller.formError()}
-        status={props.controller.formStatus()}
-        onChange={props.controller.handleFormChange()}
-        onNameChange={props.controller.handleFormNameChange()}
-        onUsernameChange={props.controller.handleFormUsernameChange()}
-        onPasswordChange={props.controller.handleFormPasswordChange()}
-        onSubmit={props.controller.submitForm}
-        onBack={props.controller.resetForm}
+        busy={props.form.state.busy()}
+        error={props.form.state.error()}
+        status={props.form.state.status()}
+        onChange={props.form.change.value}
+        onNameChange={props.form.change.name}
+        onUsernameChange={props.form.change.username}
+        onPasswordChange={props.form.change.password}
+        onSubmit={props.form.submit}
+        onBack={props.form.reset}
       />
       <div class="shrink-0 pb-5">
         <Button
           variant="primary"
           size="large"
-          onClick={props.controller.submitForm}
-          disabled={props.controller.formBusy()}
+          onClick={props.form.submit}
+          disabled={props.form.state.busy()}
           class="px-3 py-1.5"
         >
-          {props.controller.formBusy()
+          {props.form.state.busy()
             ? language.t("dialog.server.add.checking")
-            : props.controller.isAddMode()
+            : props.form.state.adding()
               ? language.t("dialog.server.add.button")
               : language.t("common.save")}
         </Button>

packages/app/src/components/server/server-management-controller.ts

@@ -0,0 +1,336 @@
+import { useNavigate } from "@solidjs/router"
+import { useMutation } from "@tanstack/solid-query"
+import { createEffect, createMemo, createResource, onCleanup } from "solid-js"
+import { createStore } from "solid-js/store"
+import { useGlobal } from "@/context/global"
+import { useLanguage } from "@/context/language"
+import { usePlatform } from "@/context/platform"
+import { normalizeServerUrl, ServerConnection, useServer } from "@/context/server"
+import { useSettings } from "@/context/settings"
+import { useTabs } from "@/context/tabs"
+import { type ServerHealth, useCheckServerHealth } from "@/utils/server-health"
+import { detectServerProtocol } from "@/utils/server-protocol"
+import { showToast } from "@/utils/toast"
+import { createServerHealthPreview, replaceServerConnection, type ServerFormValues } from "./server-management"
+
+const DEFAULT_USERNAME = "opencode"
+
+type FormMode = "list" | "add" | "edit"
+
+function showRequestError(language: ReturnType<typeof useLanguage>, err: unknown) {
+  showToast({
+    variant: "error",
+    title: language.t("common.requestFailed"),
+    description: err instanceof Error ? err.message : String(err),
+  })
+}
+
+function useDefaultServer() {
+  const language = useLanguage()
+  const platform = usePlatform()
+  const [defaultKey, defaultKeyActions] = createResource(
+    async () => {
+      try {
+        return (await platform.getDefaultServer?.()) ?? null
+      } catch (err) {
+        showRequestError(language, err)
+        return null
+      }
+    },
+    { initialValue: null },
+  )
+
+  const set = async (key: ServerConnection.Key | null) => {
+    try {
+      await platform.setDefaultServer?.(key)
+      defaultKeyActions.mutate(key)
+    } catch (err) {
+      showRequestError(language, err)
+    }
+  }
+
+  return {
+    key: () => defaultKey.latest,
+    available: createMemo(() => !!platform.getDefaultServer && !!platform.setDefaultServer),
+    set,
+  }
+}
+
+function useServerMutations() {
+  const server = useServer()
+  const tabs = useTabs()
+
+  return {
+    add: (connection: ServerConnection.Http) => server.add(connection),
+    replace: (original: ServerConnection.Http, next: ServerConnection.Http) =>
+      replaceServerConnection(original, next, {
+        active: () => server.key,
+        removeTabs: (key) => tabs.removeServer(key),
+        add: (connection) => server.add(connection),
+        setActive: (key) => server.setActive(key),
+        remove: (key) => server.remove(key),
+      }),
+  }
+}
+
+export function useServerActionsController() {
+  const server = useServer()
+  const tabs = useTabs()
+  const platform = usePlatform()
+  const language = useLanguage()
+  const defaults = useDefaultServer()
+
+  const remove = async (key: ServerConnection.Key) => {
+    try {
+      if (key.startsWith("wsl:")) await platform.wslServers?.removeServer(key)
+      tabs.removeServer(key)
+      server.remove(key)
+      if ((await platform.getDefaultServer?.()) === key) await defaults.set(null)
+    } catch (err) {
+      showRequestError(language, err)
+    }
+  }
+
+  return { defaults, connection: { canRemove: server.canRemove, remove } }
+}
+
+export type ServerActionsController = ReturnType<typeof useServerActionsController>
+
+export function useServerCollectionController() {
+  const server = useServer()
+  const global = useGlobal()
+  const settings = useSettings()
+  const actions = useServerActionsController()
+
+  const items = createMemo(() => {
+    const current = server.current
+    const list = server.list
+    if (!current) return list
+    if (!list.includes(current)) return [current, ...list]
+    return [current, ...list.filter((item) => item !== current)]
+  })
+  const current = createMemo<ServerConnection.Any | undefined>(() =>
+    settings.general.newLayoutDesigns()
+      ? undefined
+      : (items().find((item) => ServerConnection.key(item) === server.key) ?? items()[0]),
+  )
+  const sorted = createMemo(() => {
+    const raw = items()
+    const list = settings.general.newLayoutDesigns()
+      ? raw
+      : raw.filter((item) => global.ensureServerCtx(item).sdk.protocolKind() !== "v2")
+    if (!list.length) return list
+    const active = current()
+    const order = new Map(list.map((item, index) => [item, index] as const))
+    const rank = (value?: ServerHealth) => {
+      if (value?.healthy === true) return 0
+      if (value?.healthy === false) return 2
+      return 1
+    }
+    return list.slice().sort((a, b) => {
+      if (a === active) return -1
+      if (b === active) return 1
+      const diff =
+        rank(global.servers.health[ServerConnection.key(a)]) - rank(global.servers.health[ServerConnection.key(b)])
+      if (diff !== 0) return diff
+      return (order.get(a) ?? 0) - (order.get(b) ?? 0)
+    })
+  })
+
+  return {
+    collection: {
+      items: sorted,
+      current,
+      health: () => global.servers.health,
+    },
+    ...actions,
+  }
+}
+
+export type ServerCollectionController = ReturnType<typeof useServerCollectionController>
+
+export function useServerDomainController(options: { onSelect?: () => void } = {}) {
+  const navigate = useNavigate()
+  const server = useServer()
+  const global = useGlobal()
+  const collection = useServerCollectionController()
+
+  const select = async (connection: ServerConnection.Any) => {
+    if (global.servers.health[ServerConnection.key(connection)]?.healthy === false) return
+    options.onSelect?.()
+    navigate("/")
+    queueMicrotask(() => server.setActive(ServerConnection.key(connection)))
+  }
+
+  return { ...collection, selection: { select } }
+}
+
+export type ServerDomainController = ReturnType<typeof useServerDomainController>
+
+export function useServerFormController(options: { onSelect?: () => void; navigateOnAdd?: boolean } = {}) {
+  const navigate = useNavigate()
+  const server = useServer()
+  const global = useGlobal()
+  const platform = usePlatform()
+  const language = useLanguage()
+  const settings = useSettings()
+  const mutations = useServerMutations()
+  const checkServerHealth = useCheckServerHealth()
+  const healthPreview = createServerHealthPreview(checkServerHealth)
+  const [store, setStore] = createStore({
+    mode: "list" as FormMode,
+    originalUrl: undefined as string | undefined,
+    values: { url: "", name: "", username: DEFAULT_USERNAME, password: "" },
+    error: "",
+    status: undefined as boolean | undefined,
+  })
+
+  onCleanup(healthPreview.cancel)
+
+  const reset = () => {
+    healthPreview.cancel()
+    setStore({
+      mode: "list",
+      originalUrl: undefined,
+      values: { url: "", name: "", username: DEFAULT_USERNAME, password: "" },
+      error: "",
+      status: undefined,
+    })
+  }
+  const allServers = () => {
+    if (!server.current || server.list.includes(server.current)) return server.list
+    return [server.current, ...server.list]
+  }
+  const editing = createMemo(() =>
+    allServers().find((item) => item.type === "http" && item.http.url === store.originalUrl),
+  )
+
+  const request = useMutation(() => ({
+    mutationFn: async () => {
+      const normalized = normalizeServerUrl(store.values.url)
+      if (!normalized) {
+        reset()
+        return
+      }
+
+      const original = store.mode === "edit" ? editing() : undefined
+      if (store.mode === "edit" && !original) return
+      const name = store.values.name.trim() || undefined
+      const username = store.values.username || undefined
+      const password = store.values.password || undefined
+      if (
+        original?.type === "http" &&
+        normalized === original.http.url &&
+        name === original.displayName &&
+        username === original.http.username &&
+        password === original.http.password
+      ) {
+        reset()
+        return
+      }
+
+      const connection: ServerConnection.Http = {
+        type: "http",
+        displayName: name,
+        http: {
+          url: normalized,
+          username: store.mode === "add" && !password ? undefined : username,
+          password,
+        },
+      }
+      const result = await checkServerHealth(connection.http)
+      if (!result.healthy) {
+        setStore("error", language.t("dialog.server.add.error"))
+        return
+      }
+      if (
+        !settings.general.newLayoutDesigns() &&
+        (await detectServerProtocol(connection.http, platform.fetch ?? globalThis.fetch)) === "v2"
+      ) {
+        setStore("error", language.t("dialog.server.add.error"))
+        return
+      }
+
+      if (original?.type === "http") {
+        if (normalized === original.http.url) mutations.add(connection)
+        if (normalized !== original.http.url) mutations.replace(original, connection)
+        reset()
+        return
+      }
+
+      reset()
+      if (options.navigateOnAdd === false) {
+        mutations.add(connection)
+        options.onSelect?.()
+        return
+      }
+      mutations.add(connection)
+      options.onSelect?.()
+      navigate("/")
+    },
+  }))
+
+  const preview = () => void healthPreview.preview(store.values, (status) => setStore("status", status))
+  const change = (field: keyof ServerFormValues, value: string) => {
+    if (request.isPending) return
+    setStore("values", field, value)
+    setStore("error", "")
+    if (field !== "name") preview()
+  }
+  const startAdd = () => {
+    reset()
+    setStore("mode", "add")
+  }
+  const startEdit = (connection: ServerConnection.Http) => {
+    reset()
+    setStore({
+      mode: "edit",
+      originalUrl: connection.http.url,
+      values: {
+        url: connection.http.url,
+        name: connection.displayName ?? "",
+        username: connection.http.username ?? "",
+        password: connection.http.password ?? "",
+      },
+      error: "",
+      status: global.servers.health[ServerConnection.key(connection)]?.healthy,
+    })
+  }
+  const submit = () => {
+    if (store.mode === "list" || request.isPending) return
+    setStore("error", "")
+    request.mutate()
+  }
+
+  createEffect(() => {
+    if (store.mode !== "edit") return
+    if (editing()) return
+    reset()
+  })
+
+  return {
+    state: {
+      mode: () => store.mode,
+      open: () => store.mode !== "list",
+      adding: () => store.mode === "add",
+      busy: () => request.isPending,
+      value: () => store.values.url,
+      name: () => store.values.name,
+      username: () => store.values.username,
+      password: () => store.values.password,
+      error: () => store.error,
+      status: () => store.status,
+    },
+    change: {
+      value: (value: string) => change("url", value),
+      name: (value: string) => change("name", value),
+      username: (value: string) => change("username", value),
+      password: (value: string) => change("password", value),
+    },
+    start: { add: startAdd, edit: startEdit },
+    reset,
+    submit,
+  }
+}
+
+export type ServerFormController = ReturnType<typeof useServerFormController>

packages/app/src/components/server/server-management.test.ts

@@ -0,0 +1,99 @@
+import { describe, expect, test } from "bun:test"
+import { ServerConnection } from "@/context/server"
+import { createServerHealthPreview, replaceServerConnection, type ServerFormValues } from "./server-management"
+
+function deferred<T>() {
+  let resolve!: (value: T) => void
+  const promise = new Promise<T>((done) => {
+    resolve = done
+  })
+  return { promise, resolve }
+}
+
+const values = (url: string): ServerFormValues => ({ url, name: "", username: "opencode", password: "" })
+
+describe("createServerHealthPreview", () => {
+  test("ignores an older response that resolves after the latest response", async () => {
+    const first = deferred<{ healthy: boolean }>()
+    const second = deferred<{ healthy: boolean }>()
+    const requests = [first, second]
+    const status: Array<boolean | undefined> = []
+    const preview = createServerHealthPreview(() => requests.shift()!.promise)
+
+    const older = preview.preview(values("old.example.com"), (value) => status.push(value))
+    const latest = preview.preview(values("new.example.com"), (value) => status.push(value))
+    second.resolve({ healthy: true })
+    await latest
+    first.resolve({ healthy: false })
+    await older
+
+    expect(status).toEqual([undefined, undefined, true])
+  })
+
+  test("an incomplete value invalidates an in-flight response", async () => {
+    const request = deferred<{ healthy: boolean }>()
+    const status: Array<boolean | undefined> = []
+    const preview = createServerHealthPreview(() => request.promise)
+
+    const pending = preview.preview(values("server.example.com"), (value) => status.push(value))
+    await preview.preview(values("server"), (value) => status.push(value))
+    request.resolve({ healthy: true })
+    await pending
+
+    expect(status).toEqual([undefined, undefined])
+  })
+
+  test("cancellation prevents an in-flight response from updating status", async () => {
+    const request = deferred<{ healthy: boolean }>()
+    const status: Array<boolean | undefined> = []
+    const preview = createServerHealthPreview(() => request.promise)
+
+    const pending = preview.preview(values("server.example.com"), (value) => status.push(value))
+    preview.cancel()
+    request.resolve({ healthy: true })
+    await pending
+
+    expect(status).toEqual([undefined])
+  })
+})
+
+describe("replaceServerConnection", () => {
+  const original: ServerConnection.Http = { type: "http", http: { url: "https://old.example.com" } }
+  const next: ServerConnection.Http = { type: "http", http: { url: "https://new.example.com" } }
+
+  test("moves active selection after adding the replacement and removes the original", () => {
+    const calls: string[] = []
+
+    replaceServerConnection(original, next, {
+      active: () => ServerConnection.key(original),
+      removeTabs: (key) => calls.push(`tabs:${key}`),
+      add: (server) => {
+        calls.push(`add:${ServerConnection.key(server)}`)
+        return server
+      },
+      setActive: (key) => calls.push(`active:${key}`),
+      remove: (key) => calls.push(`remove:${key}`),
+    })
+
+    expect(calls).toEqual([
+      "tabs:https://old.example.com",
+      "add:https://new.example.com",
+      "active:https://new.example.com",
+      "remove:https://old.example.com",
+    ])
+  })
+
+  test("keeps the original when the replacement cannot be added", () => {
+    const removed: ServerConnection.Key[] = []
+
+    replaceServerConnection(original, next, {
+      active: () => ServerConnection.key(original),
+      removeTabs: () => {},
+      add: () => undefined,
+      setActive: () => {},
+      remove: (key) => removed.push(key),
+    })
+
+    expect(removed).toEqual([])
+  })
+})

packages/app/src/components/server/server-management.ts

@@ -0,0 +1,60 @@
+import { normalizeServerUrl, ServerConnection } from "@/context/server"
+import type { ServerHealth } from "@/utils/server-health"
+
+export type ServerFormValues = {
+  url: string
+  name: string
+  username: string
+  password: string
+}
+
+export function createServerHealthPreview(
+  check: (server: ServerConnection.HttpBase) => Promise<Pick<ServerHealth, "healthy">>,
+) {
+  let generation = 0
+
+  const cancel = () => {
+    generation += 1
+  }
+
+  const preview = async (values: ServerFormValues, setStatus: (value: boolean | undefined) => void) => {
+    const current = ++generation
+    setStatus(undefined)
+    const normalized = normalizeServerUrl(values.url)
+    if (!normalized) return
+    const host = normalized.replace(/^https?:\/\//, "").split("/")[0]
+    if (!host) return
+    if (!host.includes("localhost") && !host.startsWith("127.0.0.1") && !host.includes(".") && !host.includes(":"))
+      return
+
+    const http: ServerConnection.HttpBase = { url: normalized }
+    if (values.username) http.username = values.username
+    if (values.password) http.password = values.password
+    const result = await check(http)
+    if (current !== generation) return
+    setStatus(result.healthy)
+  }
+
+  return { cancel, preview }
+}
+
+export function replaceServerConnection(
+  original: ServerConnection.Http,
+  next: ServerConnection.Http,
+  operations: {
+    active: () => ServerConnection.Key | undefined
+    removeTabs: (key: ServerConnection.Key) => void
+    add: (server: ServerConnection.Http) => ServerConnection.Any | undefined
+    setActive: (key: ServerConnection.Key) => void
+    remove: (key: ServerConnection.Key) => void
+  },
+) {
+  const originalKey = ServerConnection.key(original)
+  const active = operations.active()
+  operations.removeTabs(originalKey)
+  const added = operations.add(next)
+  if (!added) return
+  const nextActive = active === originalKey ? ServerConnection.key(added) : active
+  if (nextActive) operations.setActive(nextActive)
+  operations.remove(originalKey)
+}

packages/app/src/components/server/server-row-menu.tsx

@@ -2,13 +2,13 @@ import { Icon as IconV2 } from "@opencode-ai/ui/v2/icon"
 import { IconButtonV2 } from "@opencode-ai/ui/v2/icon-button-v2"
 import { MenuV2 } from "@opencode-ai/ui/v2/menu-v2"
 import { type Component, Show } from "solid-js"
-import { useServerManagementController } from "@/components/dialog-select-server"
+import type { ServerActionsController } from "@/components/server/server-management-controller"
 import { useLanguage } from "@/context/language"
 import { ServerConnection } from "@/context/server"
 
 export const ServerRowMenu: Component<{
   server: ServerConnection.Any
-  controller: ReturnType<typeof useServerManagementController>
+  domain: ServerActionsController
   onEdit: (server: ServerConnection.Http) => void
   open?: boolean
   onOpenChange?: (open: boolean) => void
@@ -19,13 +19,13 @@ export const ServerRowMenu: Component<{
     <ServerRowMenuView
       server={props.server}
       labels={serverMenuLabels(language)}
-      canDefault={props.controller.canDefault()}
-      isDefault={props.controller.defaultKey() === key}
-      canRemove={props.controller.canRemove(key)}
+      canDefault={props.domain.defaults.available()}
+      isDefault={props.domain.defaults.key() === key}
+      canRemove={props.domain.connection.canRemove(key)}
       onEdit={props.onEdit}
-      onSetDefault={() => props.controller.setDefault(key)}
-      onRemoveDefault={() => props.controller.setDefault(null)}
-      onRemove={() => props.controller.handleRemove(key)}
+      onSetDefault={() => props.domain.defaults.set(key)}
+      onRemoveDefault={() => props.domain.defaults.set(null)}
+      onRemove={() => props.domain.connection.remove(key)}
       open={props.open}
       onOpenChange={props.onOpenChange}
     />

packages/app/src/components/settings-servers.tsx

@@ -1,16 +1,19 @@
 import { Show, type Component } from "solid-js"
+import { IconButton } from "@opencode-ai/ui/icon-button"
 import { useLanguage } from "@/context/language"
-import { ServerConnectionForm, ServerConnectionList, useServerManagementController } from "./dialog-select-server"
+import { useServerDomainController, useServerFormController } from "./server/server-management-controller"
+import { ServerConnectionForm, ServerConnectionList } from "./dialog-select-server"
 
 export const SettingsServers: Component = () => {
   const language = useLanguage()
-  const controller = useServerManagementController()
+  const domain = useServerDomainController()
+  const form = useServerFormController()
 
   return (
     <div class="flex flex-col h-full overflow-y-auto no-scrollbar px-4 pb-10 sm:px-10 sm:pb-10">
       <div class="flex flex-col flex-1 min-h-0 max-w-[720px]">
         <Show
-          when={controller.isFormMode()}
+          when={form.state.open()}
           fallback={
             <>
               <div class="sticky top-0 z-10 bg-[linear-gradient(to_bottom,var(--surface-stronger-non-alpha)_calc(100%_-_24px),transparent)]">
@@ -18,13 +21,25 @@ export const SettingsServers: Component = () => {
                   <h2 class="text-16-medium text-text-strong">{language.t("status.popover.tab.servers")}</h2>
                 </div>
               </div>
-              <ServerConnectionList controller={controller} />
+              <ServerConnectionList domain={domain} onAdd={form.start.add} onEdit={form.start.edit} />
             </>
           }
         >
           <div class="flex flex-1 min-h-0 flex-col gap-4 pt-6">
-            <div class="text-16-medium text-text-strong">{controller.formTitle()}</div>
-            <ServerConnectionForm controller={controller} />
+            <div class="text-16-medium text-text-strong">
+              <div class="flex items-center gap-2 -ml-2">
+                <IconButton
+                  icon="arrow-left"
+                  variant="ghost"
+                  onClick={form.reset}
+                  aria-label={language.t("common.goBack")}
+                />
+                <span>
+                  {form.state.adding() ? language.t("dialog.server.add.title") : language.t("dialog.server.edit.title")}
+                </span>
+              </div>
+            </div>
+            <ServerConnectionForm form={form} />
           </div>
         </Show>
       </div>

packages/app/src/components/settings-v2/dialog-server-v2.tsx

@@ -6,7 +6,7 @@ import { useDialog } from "@opencode-ai/ui/context/dialog"
 import { type Component, Show, createEffect, createSignal, onCleanup, onMount } from "solid-js"
 import { useLanguage } from "@/context/language"
 import { type ServerConnection } from "@/context/server"
-import { useServerManagementController } from "../dialog-select-server"
+import { useServerFormController } from "../server/server-management-controller"
 import "./settings-v2.css"
 
 export const DialogServerV2: Component<{
@@ -15,39 +15,39 @@ export const DialogServerV2: Component<{
 }> = (props) => {
   const dialog = useDialog()
   const language = useLanguage()
-  const controller = useServerManagementController({
+  const form = useServerFormController({
     onSelect: () => dialog.close(),
     navigateOnAdd: false,
   })
   const [opened, setOpened] = createSignal(false)
 
   onMount(() => {
-    if (props.mode === "add") controller.startAdd()
-    if (props.mode === "edit" && props.server) controller.startEdit(props.server)
+    if (props.mode === "add") form.start.add()
+    if (props.mode === "edit" && props.server) form.start.edit(props.server)
     setOpened(true)
   })
 
   onCleanup(() => {
-    controller.resetForm()
+    form.reset()
   })
 
   createEffect(() => {
     if (!opened()) return
-    if (controller.isFormMode()) return
+    if (form.state.open()) return
     dialog.close()
   })
 
   const keyDown = (event: KeyboardEvent) => {
     if (event.key !== "Enter" || event.isComposing) return
     event.preventDefault()
-    controller.submitForm()
+    form.submit()
   }
 
   const title = () =>
     props.mode === "add" ? language.t("dialog.server.add.title") : language.t("dialog.server.edit.title")
 
   const submitLabel = () => {
-    if (controller.formBusy()) return language.t("dialog.server.add.checking")
+    if (form.state.busy()) return language.t("dialog.server.add.checking")
     if (props.mode === "add") return language.t("dialog.server.add.button")
     return language.t("common.save")
   }
@@ -66,16 +66,16 @@ export const DialogServerV2: Component<{
               type="text"
               appearance="large"
               class="!w-full self-stretch"
-              value={controller.formValue()}
+              value={form.state.value()}
               placeholder={language.t("dialog.server.add.placeholder")}
-              invalid={!!controller.formError()}
-              disabled={controller.formBusy()}
+              invalid={!!form.state.error()}
+              disabled={form.state.busy()}
               autofocus
-              onInput={(event) => controller.handleFormChange()(event.currentTarget.value)}
+              onInput={(event) => form.change.value(event.currentTarget.value)}
               onKeyDown={keyDown}
             />
-            <Show when={controller.formError()}>
-              <span class="settings-v2-server-dialog-error">{controller.formError()}</span>
+            <Show when={form.state.error()}>
+              <span class="settings-v2-server-dialog-error">{form.state.error()}</span>
             </Show>
           </div>
           <div class="flex w-full min-w-0 flex-col gap-2">
@@ -84,10 +84,10 @@ export const DialogServerV2: Component<{
               type="text"
               appearance="large"
               class="!w-full self-stretch"
-              value={controller.formName()}
+              value={form.state.name()}
               placeholder={language.t("dialog.server.add.namePlaceholder")}
-              disabled={controller.formBusy()}
-              onInput={(event) => controller.handleFormNameChange()(event.currentTarget.value)}
+              disabled={form.state.busy()}
+              onInput={(event) => form.change.name(event.currentTarget.value)}
               onKeyDown={keyDown}
             />
           </div>
@@ -98,10 +98,10 @@ export const DialogServerV2: Component<{
                 type="text"
                 appearance="large"
                 class="!w-full self-stretch"
-                value={controller.formUsername()}
+                value={form.state.username()}
                 placeholder={language.t("dialog.server.add.usernamePlaceholder")}
-                disabled={controller.formBusy()}
-                onInput={(event) => controller.handleFormUsernameChange()(event.currentTarget.value)}
+                disabled={form.state.busy()}
+                onInput={(event) => form.change.username(event.currentTarget.value)}
                 onKeyDown={keyDown}
               />
             </div>
@@ -111,10 +111,10 @@ export const DialogServerV2: Component<{
                 type="password"
                 appearance="large"
                 class="!w-full self-stretch"
-                value={controller.formPassword()}
+                value={form.state.password()}
                 placeholder={language.t("dialog.server.add.passwordPlaceholder")}
-                disabled={controller.formBusy()}
-                onInput={(event) => controller.handleFormPasswordChange()(event.currentTarget.value)}
+                disabled={form.state.busy()}
+                onInput={(event) => form.change.password(event.currentTarget.value)}
                 onKeyDown={keyDown}
               />
             </div>
@@ -122,10 +122,10 @@ export const DialogServerV2: Component<{
         </div>
       </DialogBody>
       <DialogFooter>
-        <ButtonV2 variant="neutral" disabled={controller.formBusy()} onClick={() => dialog.close()}>
+        <ButtonV2 variant="neutral" disabled={form.state.busy()} onClick={() => dialog.close()}>
           {language.t("common.cancel")}
         </ButtonV2>
-        <ButtonV2 variant="contrast" disabled={controller.formBusy()} onClick={controller.submitForm}>
+        <ButtonV2 variant="contrast" disabled={form.state.busy()} onClick={form.submit}>
           {submitLabel()}
         </ButtonV2>
       </DialogFooter>

packages/app/src/components/settings-v2/servers.tsx

@@ -10,7 +10,7 @@ import { ServerRowMenu } from "@/components/server/server-row-menu"
 import { ServerHealthIndicator } from "@/components/server/server-row"
 import { useLanguage } from "@/context/language"
 import { ServerConnection, serverName } from "@/context/server"
-import { useServerManagementController } from "../dialog-select-server"
+import { useServerCollectionController } from "../server/server-management-controller"
 import { DialogServerV2 } from "./dialog-server-v2"
 import { SettingsListV2 } from "./parts/list"
 import { AddServerMenu, isWslServer, useFilteredWslServers, WslServerSettings } from "@/wsl/settings"
@@ -19,16 +19,16 @@ import "./settings-v2.css"
 export const SettingsServersV2: Component = () => {
   const dialog = useDialog()
   const language = useLanguage()
-  const controller = useServerManagementController()
+  const domain = useServerCollectionController()
   const [store, setStore] = createStore({ filter: "" })
   const wslServers = useFilteredWslServers(() => store.filter)
 
   const showSearch = createMemo(
-    () => controller.sortedItems().filter((item) => !isWslServer(item)).length + wslServers().length > 1,
+    () => domain.collection.items().filter((item) => !isWslServer(item)).length + wslServers().length > 1,
   )
 
   const filtered = createMemo(() => {
-    const items = controller.sortedItems().filter((item) => !isWslServer(item))
+    const items = domain.collection.items().filter((item) => !isWslServer(item))
     const query = store.filter.trim()
     if (!query) return items
     return fuzzysort
@@ -39,11 +39,11 @@ export const SettingsServersV2: Component = () => {
   })
 
   const openAdd = () => {
-    dialog.push(() => <DialogServerV2 mode="add" />)
+    void dialog.push(() => <DialogServerV2 mode="add" />)
   }
 
   const openEdit = (server: ServerConnection.Http) => {
-    dialog.push(() => <DialogServerV2 mode="edit" server={server} />)
+    void dialog.push(() => <DialogServerV2 mode="edit" server={server} />)
   }
 
   return (
@@ -97,12 +97,12 @@ export const SettingsServersV2: Component = () => {
           }
         >
           <SettingsListV2>
-            <WslServerSettings controller={controller} servers={wslServers} />
+            <WslServerSettings domain={domain} servers={wslServers} />
             <For each={filtered()}>
               {(item) => {
                 const key = ServerConnection.key(item)
-                const health = () => controller.status()[key]
-                const isDefault = () => controller.defaultKey() === key
+                const health = () => domain.collection.health()[key]
+                const isDefault = () => domain.defaults.key() === key
                 return (
                   <div class="settings-v2-servers-row">
                     <div class="settings-v2-servers-lead">
@@ -122,10 +122,10 @@ export const SettingsServersV2: Component = () => {
                       </div>
                     </div>
                     <div class="settings-v2-servers-actions">
-                      <Show when={controller.canDefault() && isDefault()}>
+                      <Show when={domain.defaults.available() && isDefault()}>
                         <Tag>{language.t("dialog.server.status.default")}</Tag>
                       </Show>
-                      <ServerRowMenu server={item} controller={controller} onEdit={openEdit} />
+                      <ServerRowMenu server={item} domain={domain} onEdit={openEdit} />
                     </div>
                   </div>
                 )

packages/app/src/pages/home/home-projects-controller.tsx

@@ -1,5 +1,5 @@
 import { useDirectoryPicker } from "@/components/directory-picker"
-import { useServerManagementController } from "@/components/dialog-select-server"
+import { useServerActionsController } from "@/components/server/server-management-controller"
 import { useSettingsCommand } from "@/components/settings-dialog"
 import { DialogServerV2 } from "@/components/settings-v2/dialog-server-v2"
 import { type LocalProject } from "@/context/layout"
@@ -22,7 +22,7 @@ export function createHomeProjectsController(home: HomeController) {
   const language = useLanguage()
   const notification = useNotification()
   const openSettings = useSettingsCommand()
-  const serverManagement = useServerManagementController({ navigateOnAdd: false })
+  const serverManagement = useServerActionsController()
   const [_state, setState, _, ready] = persisted(
     Persist.global("home.servers", ["home.servers.v1"]),
     createStore({ collapsed: {} as Record<string, boolean> }),
@@ -56,12 +56,12 @@ export function createHomeProjectsController(home: HomeController) {
         const key = ServerConnection.key(conn)
         setState("collapsed", key, !state().collapsed[key])
       },
-      canDefault: serverManagement.canDefault,
-      defaultKey: serverManagement.defaultKey,
+      canDefault: serverManagement.defaults.available,
+      defaultKey: serverManagement.defaults.key,
       setDefault: (conn: ServerConnection.Any | undefined) =>
-        serverManagement.setDefault(conn ? ServerConnection.key(conn) : null),
-      canRemove: (conn: ServerConnection.Any) => serverManagement.canRemove(ServerConnection.key(conn)),
-      remove: (conn: ServerConnection.Any) => serverManagement.handleRemove(ServerConnection.key(conn)),
+        serverManagement.defaults.set(conn ? ServerConnection.key(conn) : null),
+      canRemove: (conn: ServerConnection.Any) => serverManagement.connection.canRemove(ServerConnection.key(conn)),
+      remove: (conn: ServerConnection.Any) => serverManagement.connection.remove(ServerConnection.key(conn)),
       edit: (conn: ServerConnection.Http) => dialog.show(() => <DialogServerV2 mode="edit" server={conn} />),
       focus: home.selection.focusServer,
     },

packages/app/src/utils/server-compat.test.ts

@@ -26,6 +26,7 @@ function setup(
         return new Response(undefined, { status: 204 })
       if (request.method === "POST" && request.url.endsWith("/prompt")) {
         return Response.json({
+          admittedSeq: 1,
           id: "msg_1",
           sessionID: "ses_1",
           timeCreated: 1,

packages/app/src/utils/server-compat.ts

@@ -229,6 +229,7 @@ function createV1Api(input: CompatibleInput): CompatibleApi {
           ],
         })
         return {
+          admittedSeq: 0,
           id: value.id ?? "",
           sessionID: value.sessionID,
           timeCreated: Date.now(),
@@ -254,6 +255,7 @@ function createV1Api(input: CompatibleInput): CompatibleApi {
           })),
         })
         return {
+          admittedSeq: 0,
           id: value.id ?? "",
           sessionID: value.sessionID,
           timeCreated: Date.now(),
@@ -278,6 +280,7 @@ function createV1Api(input: CompatibleInput): CompatibleApi {
           modelID: value.model.modelID,
         })
         return {
+          admittedSeq: 0,
           id: value.id ?? "",
           sessionID: value.sessionID,
           timeCreated: Date.now(),

packages/app/src/wsl/settings.tsx

@@ -7,7 +7,7 @@ import { MenuV2 } from "@opencode-ai/ui/v2/menu-v2"
 import { useMutation } from "@tanstack/solid-query"
 import fuzzysort from "fuzzysort"
 import { type Accessor, For, Show, createMemo } from "solid-js"
-import type { useServerManagementController } from "@/components/dialog-select-server"
+import type { ServerCollectionController } from "@/components/server/server-management-controller"
 import { ServerHealthIndicator } from "@/components/server/server-row"
 import { useLanguage } from "@/context/language"
 import { usePlatform } from "@/context/platform"
@@ -17,8 +17,6 @@ import { DialogAddWslServer } from "./dialog-add-server"
 import { useWslServers } from "./context"
 import { wslOpencodeAction, wslRuntimeRetryable } from "./settings-model"
 
-type Controller = ReturnType<typeof useServerManagementController>
-
 export function isWslServer(server: ServerConnection.Any) {
   return server.type === "sidecar" && server.variant === "wsl"
 }
@@ -28,7 +26,7 @@ export function AddServerMenu(props: { onAddServer: () => void }) {
   const dialog = useDialog()
   const language = useLanguage()
   const openAddWsl = () => {
-    dialog.push(() => <DialogAddWslServer />)
+    void dialog.push(() => <DialogAddWslServer />)
   }
   return (
     <Show
@@ -67,7 +65,7 @@ export function useFilteredWslServers(filter: Accessor<string>) {
 }
 
 export function WslServerSettings(props: {
-  controller: Controller
+  domain: Pick<ServerCollectionController, "collection" | "defaults" | "connection">
   servers: ReturnType<typeof useFilteredWslServers>
 }) {
   const platform = usePlatform()
@@ -86,7 +84,7 @@ export function WslServerSettings(props: {
   }))
 
   const remove = (key: ServerConnection.Key) => {
-    request.mutate(() => props.controller.handleRemove(key))
+    request.mutate(() => props.domain.connection.remove(key))
   }
 
   return (
@@ -100,7 +98,7 @@ export function WslServerSettings(props: {
           return (
             <div class="settings-v2-servers-row">
               <div class="settings-v2-servers-lead">
-                <ServerHealthIndicator health={props.controller.status()[key]} />
+                <ServerHealthIndicator health={props.domain.collection.health()[key]} />
                 <div class="settings-v2-servers-copy">
                   <span class="flex min-w-0 items-center gap-1">
                     <span class="settings-v2-servers-name">{item.config.distro}</span>
@@ -114,7 +112,7 @@ export function WslServerSettings(props: {
                 </div>
               </div>
               <div class="settings-v2-servers-actions">
-                <Show when={props.controller.canDefault() && props.controller.defaultKey() === key}>
+                <Show when={props.domain.defaults.available() && props.domain.defaults.key() === key}>
                   <Tag>{language.t("dialog.server.status.default")}</Tag>
                 </Show>
                 <Show when={opencodeAction()}>
@@ -145,13 +143,13 @@ export function WslServerSettings(props: {
                             {language.t("wsl.server.retryStart")}
                           </MenuV2.Item>
                         </Show>
-                        <Show when={props.controller.canDefault() && props.controller.defaultKey() !== key}>
-                          <MenuV2.Item onSelect={() => props.controller.setDefault(key)}>
+                        <Show when={props.domain.defaults.available() && props.domain.defaults.key() !== key}>
+                          <MenuV2.Item onSelect={() => props.domain.defaults.set(key)}>
                             {language.t("dialog.server.menu.default")}
                           </MenuV2.Item>
                         </Show>
-                        <Show when={props.controller.canDefault() && props.controller.defaultKey() === key}>
-                          <MenuV2.Item onSelect={() => props.controller.setDefault(null)}>
+                        <Show when={props.domain.defaults.available() && props.domain.defaults.key() === key}>
+                          <MenuV2.Item onSelect={() => props.domain.defaults.set(null)}>
                             {language.t("dialog.server.menu.defaultRemove")}
                           </MenuV2.Item>
                         </Show>

packages/cli/src/acp/service.ts

@@ -244,10 +244,7 @@ export function make(input: { readonly client: OpenCodeClient; readonly connecti
       return {}
     },
     forkSession: async (params) => {
-      const forked = await input.client.session.fork({
-        sessionID: params.sessionId,
-        boundary: { type: "through" },
-      })
+      const forked = await input.client.session.fork({ sessionID: params.sessionId })
       const state = await attach(forked, forked.location.directory, params.mcpServers ?? [])
       await replay(state)
       return { sessionId: state.id, configOptions: configOptions(state) }

packages/cli/src/session-target.ts

@@ -105,7 +105,7 @@ async function selectSession(input: {
     return {
       session: input.fork
         ? await input.client.session
-            .fork({ sessionID: explicit.id, boundary: { type: "through" } }, ...requestOptions(input.signal))
+            .fork({ sessionID: explicit.id }, ...requestOptions(input.signal))
             .catch((error) => {
               throw new SessionTargetMutationError(error)
             })
@@ -118,11 +118,9 @@ async function selectSession(input: {
   if (!selected) return { session: undefined, location }
   return {
     session: input.fork
-      ? await input.client.session
-          .fork({ sessionID: selected.id, boundary: { type: "through" } }, ...requestOptions(input.signal))
-          .catch((error) => {
-            throw new SessionTargetMutationError(error)
-          })
+      ? await input.client.session.fork({ sessionID: selected.id }, ...requestOptions(input.signal)).catch((error) => {
+          throw new SessionTargetMutationError(error)
+        })
       : selected,
   }
 }

packages/cli/test/run/noninteractive.test.ts

@@ -267,7 +267,7 @@ async function run(input: {
     values.push(...input.turn(messageID))
     wake?.()
     wake = undefined
-    return ok({ id: messageID, sessionID: "ses_1", timeCreated: 1 }) as never
+    return ok({ admittedSeq: 1, id: messageID, sessionID: "ses_1", timeCreated: 1 }) as never
   })
   await runNonInteractivePrompt({
     client: sdk,

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

@@ -136,7 +136,7 @@ export type Endpoint5_4Input = { readonly sessionID: Session.ID }
 export type Endpoint5_4Output = void
 export type SessionRemoveOperation<E = never> = (input: Endpoint5_4Input) => Effect.Effect<Endpoint5_4Output, E>
 
-export type Endpoint5_5Input = { readonly sessionID: Session.ID; readonly boundary: Session.ForkRequestBoundary }
+export type Endpoint5_5Input = { readonly sessionID: Session.ID; readonly messageID?: SessionMessage.ID | undefined }
 export type Endpoint5_5Output = Session.Info
 export type SessionForkOperation<E = never> = (input: Endpoint5_5Input) => Effect.Effect<Endpoint5_5Output, E>
 
@@ -342,10 +342,8 @@ export type Endpoint5_26Output =
           readonly data: {
             readonly sessionID: Session.ID
             readonly parentID: Session.ID
-            readonly boundary: Session.ForkBoundary
-            readonly instructions?:
-              | { readonly [x: string & Brand.Brand<"Instruction.Key">]: string & Brand.Brand<"Instruction.Hash"> }
-              | undefined
+            readonly parentSeq: number
+            readonly from?: SessionMessage.ID | undefined
           }
         }
       | {

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

@@ -329,7 +329,7 @@ const Endpoint5_4 = (raw: RawClient["server.session"]) => (input: Endpoint5_4Inp
 
 const Endpoint5_5 = (raw: RawClient["server.session"]) => (input: Endpoint5_5Input) =>
   preserveEffect<Endpoint5_5Output>()(
-    raw["session.fork"]({ params: { sessionID: input["sessionID"] }, payload: { boundary: input["boundary"] } }).pipe(
+    raw["session.fork"]({ params: { sessionID: input["sessionID"] }, payload: { messageID: input["messageID"] } }).pipe(
       Effect.mapError(mapClientError),
       Effect.map((value) => value.data),
     ),

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

@@ -510,7 +510,7 @@ export function make(options: ClientOptions) {
           {
             method: "POST",
             path: `/api/session/${encodeURIComponent(input.sessionID)}/fork`,
-            body: { boundary: input["boundary"] },
+            body: { messageID: input["messageID"] },
             successStatus: 200,
             declaredStatuses: [404, 400, 401],
             empty: false,

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

@@ -14,8 +14,6 @@ export type PermissionEffect = "allow" | "deny" | "ask"
 
 export type PluginInfo = { id: string }
 
-export type SessionForkBoundary = { type: "before"; messageID: string } | { type: "through"; messageID: string }
-
 export type MoneyUSD = number
 
 export type TokenUsageInfo = {
@@ -45,7 +43,13 @@ export type PromptMention = { start: number; end: number; text: string }
 
 export type SessionPendingSyntheticData = { text: string; description?: string; metadata?: { [x: string]: JsonValue } }
 
-export type SessionPendingCompaction = { id: string; sessionID: string; timeCreated: number; type: "compaction" }
+export type SessionPendingCompaction = {
+  admittedSeq: number
+  id: string
+  sessionID: string
+  timeCreated: number
+  type: "compaction"
+}
 
 export type SessionMessageAgentSelected = {
   id: string
@@ -624,7 +628,7 @@ export type SessionForked = {
   type: "session.forked"
   durable: { aggregateID: string; seq: number; version: 2 }
   location?: LocationRef
-  data: { sessionID: string; parentID: string; boundary: SessionForkBoundary; instructions?: { [x: string]: string } }
+  data: { sessionID: string; parentID: string; parentSeq: number; from?: string }
 }
 
 export type SessionInputPromoted = {
@@ -1206,6 +1210,7 @@ export type PromptFileAttachment = {
 export type PromptAgentAttachment = { name: string; mention?: PromptMention }
 
 export type SessionPendingSynthetic = {
+  admittedSeq: number
   id: string
   sessionID: string
   timeCreated: number
@@ -1750,7 +1755,7 @@ export type PermissionRuleset = Array<PermissionRule>
 export type SessionInfo = {
   id: string
   parentID?: string
-  fork?: { sessionID: string; boundary: SessionForkBoundary }
+  fork?: { sessionID: string; messageID?: string }
   projectID: string
   agent?: string
   model?: ModelRef
@@ -1961,6 +1966,7 @@ export type AgentInfo = {
 export type SessionsResponse = { data: Array<SessionInfo>; cursor: { previous?: string | null; next?: string | null } }
 
 export type SessionPendingUser = {
+  admittedSeq: number
   id: string
   sessionID: string
   timeCreated: number
@@ -2696,9 +2702,7 @@ export type SessionRemoveOutput = void
 
 export type SessionForkInput = {
   readonly sessionID: { readonly sessionID: string }["sessionID"]
-  readonly boundary: {
-    readonly boundary: { readonly type: "before"; readonly messageID: string } | { readonly type: "through" }
-  }["boundary"]
+  readonly messageID?: { readonly messageID?: string | undefined }["messageID"]
 }
 
 export type SessionForkOutput = { data: SessionInfo }["data"]

packages/client/test/effect.test.ts

@@ -268,6 +268,7 @@ const session = {
 
 const admission = {
   data: {
+    admittedSeq: 0,
     id: "msg_test",
     sessionID: "ses_test",
     type: "user",
@@ -280,6 +281,7 @@ const admission = {
 const compactionAdmission = {
   data: {
     type: "compaction",
+    admittedSeq: 1,
     id: "msg_compaction",
     sessionID: "ses_test",
     timeCreated: 1_717_171_717_000,

packages/client/test/promise.test.ts

@@ -304,6 +304,7 @@ test("session.pending.list uses the public HTTP contract", async () => {
   const requests: Array<{ method: string; url: string }> = []
   const pending = [
     {
+      admittedSeq: 3,
       id: "msg_pending",
       sessionID: "ses_test",
       timeCreated: 1_717_171_717_000,
@@ -546,6 +547,7 @@ const session = {
 
 const admission = {
   data: {
+    admittedSeq: 0,
     id: "msg_test",
     sessionID: "ses_test",
     type: "user",
@@ -557,6 +559,7 @@ const admission = {
 
 const syntheticAdmission = {
   data: {
+    admittedSeq: 1,
     id: "msg_synthetic",
     sessionID: "ses_test",
     type: "synthetic",
@@ -569,6 +572,7 @@ const syntheticAdmission = {
 const compactionAdmission = {
   data: {
     type: "compaction",
+    admittedSeq: 1,
     id: "msg_compaction",
     sessionID: "ses_test",
     timeCreated: 1_717_171_717_000,

packages/core/schema.json

@@ -1,9 +1,9 @@
 {
   "version": "7",
   "dialect": "sqlite",
-  "id": "db37a97f-9b5e-4c87-be8b-4feace35136c",
+  "id": "a4ba73b4-21bc-41ab-a415-94e2ca38d798",
   "prevIds": [
-    "a4ba73b4-21bc-41ab-a415-94e2ca38d798"
+    "5f0a1db8-d4bf-42c3-becb-96b46fe66bed"
   ],
   "ddl": [
     {
@@ -1266,7 +1266,17 @@
       "autoincrement": false,
       "default": null,
       "generated": null,
-      "name": "fork_boundary",
+      "name": "fork_message_id",
+      "entityType": "columns",
+      "table": "session"
+    },
+    {
+      "type": "integer",
+      "notNull": false,
+      "autoincrement": false,
+      "default": null,
+      "generated": null,
+      "name": "fork_seq",
       "entityType": "columns",
       "table": "session"
     },

packages/core/src/codemode/instructions.ts

@@ -6,9 +6,7 @@ import { Instructions } from "../instructions/index"
 import { CodeModeCatalog } from "./catalog"
 
 // prettier-ignore
-const prompt = (hasMoreTools: boolean) => `The Code Mode tool catalog below is ${hasMoreTools ? "partial" : "complete"}.
-
-${hasMoreTools ? "The Code Mode catalog and `search` results are" : "This catalog is"} the complete set of tools available within Code Mode. Tools presented elsewhere are not available in this runtime.${hasMoreTools ? `
+const prompt = (hasMoreTools: boolean) => `The Code Mode tool catalog below is ${hasMoreTools ? "partial" : "complete"}.${hasMoreTools ? `
 
 ## Search
 

packages/core/src/codemode/tool.ts

@@ -33,7 +33,7 @@ type CollectedFiles = {
 
 // Invariant model-facing guidance; the changing tool catalog is delivered through Instructions.
 const description = [
-  "Run JavaScript in a confined Code Mode runtime to orchestrate tool calls and compose their results.",
+  "Run JavaScript to orchestrate tool calls and compose their results through `{ code }` in a confined Code Mode runtime.",
   "Imports, direct filesystem access, and timers are unavailable. Do not use `fetch`; all external access goes through `tools`.",
   "Within `{ code }`, the only callable tools are those explicitly listed in the Code Mode catalog instructions or returned by `search`. Inside `{ code }`, ignore tools shown outside the Code Mode catalog. They are not available in the Code Mode runtime.",
   'Call tools through `tools` using only exact paths and signatures from the catalog. Do not infer or normalize tool names; preserve bracket notation such as `tools.<namespace>["tool-name"](input)`.',

packages/core/src/config.ts

@@ -393,8 +393,7 @@ export const layer = (options?: Options) => Layer.effect(
         const key = JSON.stringify(target)
         if (watched.has(key)) continue
         watched.add(key)
-        const stream = yield* watcher.subscribe(target)
-        yield* stream.pipe(
+        yield* watcher.subscribe(target).pipe(
           Stream.runForEach((update) => PubSub.publish(updates, update)),
           Effect.forkScoped({ startImmediately: true }),
         )

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

@@ -57,6 +57,5 @@ export const migrations = (
     import("./migration/20260716020354_kv"),
     import("./migration/20260722011141_delete_tool_progress_events"),
     import("./migration/20260722170000_canonical_tool_results"),
-    import("./migration/20260729022634_session_fork_boundary"),
   ])
 ).map((module) => module.default) satisfies DatabaseMigration.Migration[]

packages/core/src/database/migration/20260729022634_session_fork_boundary.ts

@@ -1,13 +0,0 @@
-import { Effect } from "effect"
-import type { DatabaseMigration } from "../migration"
-
-export default {
-  id: "20260729022634_session_fork_boundary",
-  up(tx) {
-    return Effect.gen(function* () {
-      yield* tx.run(`ALTER TABLE \`session\` ADD \`fork_boundary\` text;`)
-      yield* tx.run(`ALTER TABLE \`session\` DROP COLUMN \`fork_message_id\`;`)
-      yield* tx.run(`ALTER TABLE \`session\` DROP COLUMN \`fork_seq\`;`)
-    })
-  },
-} satisfies DatabaseMigration.Migration

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

@@ -213,7 +213,8 @@ export default {
           \`workspace_id\` text,
           \`parent_id\` text,
           \`fork_session_id\` text,
-          \`fork_boundary\` text,
+          \`fork_message_id\` text,
+          \`fork_seq\` integer,
           \`slug\` text NOT NULL,
           \`directory\` text NOT NULL,
           \`path\` text,

packages/core/src/filesystem/location-watcher.ts

@@ -47,12 +47,13 @@ const layer = Layer.effect(
       const home = path.resolve(location.directory) === path.resolve(os.homedir())
 
       if (!home && location.vcs) {
-        const updates = yield* watcher.subscribe({
-          path: location.directory,
-          type: "directory",
-          ignore: [...Ignore.PATTERNS, ...config, ...protecteds(location.directory)],
-        })
-        yield* updates.pipe(Stream.runForEach(publish), Effect.forkScoped)
+        yield* watcher
+          .subscribe({
+            path: location.directory,
+            type: "directory",
+            ignore: [...Ignore.PATTERNS, ...config, ...protecteds(location.directory)],
+          })
+          .pipe(Stream.runForEach(publish), Effect.forkScoped)
       }
       if (home) {
         yield* Effect.logInfo("location watcher skipped home directory", { directory: location.directory })
@@ -67,8 +68,9 @@ const layer = Layer.effect(
           const ignore = (yield* fs.readDirectoryEntries(vcs).pipe(Effect.catch(() => Effect.succeed([])))).flatMap(
             (entry) => (entry.name === "HEAD" ? [] : [entry.name]),
           )
-          const updates = yield* watcher.subscribe({ path: vcs, type: "directory", ignore })
-          yield* updates.pipe(Stream.runForEach(publish), Effect.forkScoped)
+          yield* watcher
+            .subscribe({ path: vcs, type: "directory", ignore })
+            .pipe(Stream.runForEach(publish), Effect.forkScoped)
         }
       }
     }).pipe(

packages/core/src/filesystem/watcher.ts

@@ -59,7 +59,7 @@ export interface NativeInterface {
 export class Native extends Context.Service<Native, NativeInterface>()("@opencode/Watcher/Native") {}
 
 export interface Interface {
-  readonly subscribe: (input: WatchInput) => Effect.Effect<Stream.Stream<Update>>
+  readonly subscribe: (input: WatchInput) => Stream.Stream<Update>
 }
 
 export const Options = Schema.Struct({
@@ -83,7 +83,7 @@ export const layer = (options?: Options) =>
     Service,
     Effect.gen(function* () {
       if (options?.enabled === false) {
-        return Service.of({ subscribe: () => Effect.succeed(Stream.empty) })
+        return Service.of({ subscribe: () => Stream.empty })
       }
       const native = yield* Native
 
@@ -131,19 +131,11 @@ export const layer = (options?: Options) =>
       const subscribe = (input: WatchInput) => {
         const target = path.resolve(input.path)
         const ignore = [...new Set(input.type === "directory" ? (input.ignore ?? []) : [])].toSorted()
-        return Effect.gen(function* () {
-          yield* Effect.logInfo("watcher subscribe", {
-            path: target,
-            type: input.type,
-            ignores: ignore.length,
-          })
-          return Stream.unwrap(
-            Effect.gen(function* () {
-              const pubsub = yield* RcMap.get(watchers, { type: input.type, target, ignore })
-              return Stream.fromPubSub(pubsub)
-            }),
-          )
-        })
+        return Stream.unwrap(
+          RcMap.get(watchers, { type: input.type, target, ignore }).pipe(
+            Effect.map((pubsub) => Stream.fromPubSub(pubsub)),
+          ),
+        )
       }
 
       return Service.of({ subscribe })

packages/core/src/plugin/supervisor.ts

@@ -253,8 +253,7 @@ const layer = Layer.effect(
         // inside), so don't watch what can't trigger anything.
         if (yield* fs.isDir(operation.target)) continue
         watched.add(operation.target)
-        const updates = yield* watcher.subscribe({ path: operation.target, type: "file" })
-        yield* updates.pipe(
+        yield* watcher.subscribe({ path: operation.target, type: "file" }).pipe(
           Stream.runForEach(() => PubSub.publish(configuredChanges, undefined)),
           Effect.catchCause((cause) =>
             Effect.logError("configured plugin watch failed", { target: operation.target, cause }),

packages/core/src/session.ts

@@ -28,12 +28,11 @@ import { fromRow } from "./session/info"
 import { SessionRunner } from "./session/runner/index"
 import { SessionStore } from "./session/store"
 import { SessionExecution } from "./session/execution"
-import { ForkEmptyError, MessageDecodeError, NotFoundError } from "./session/error"
+import { MessageDecodeError, NotFoundError } from "./session/error"
 import { makeGlobalNode } from "@opencode-ai/util/effect/app-node"
 import { LocationServiceMap } from "./location-service-map"
 import { SessionEvent } from "./session/event"
 import { SessionPending } from "./session/pending"
-import { InstructionState } from "./session/instruction-state"
 import { SessionGenerate } from "./session/generate"
 import { Snapshot } from "./snapshot"
 import { SessionRevert } from "./session/revert"
@@ -107,7 +106,7 @@ type CompactInput = {
 
 type ForkInput = {
   sessionID: SessionSchema.ID
-  boundary: Session.ForkRequestBoundary
+  messageID?: SessionMessage.ID
 }
 
 export class OperationUnavailableError extends Schema.TaggedErrorClass<OperationUnavailableError>()(
@@ -182,9 +181,7 @@ export interface Interface {
     readonly data: SessionSchema.Info[]
   }>
   readonly create: (input: CreateInput) => Effect.Effect<SessionSchema.Info, NotFoundError>
-  readonly fork: (
-    input: ForkInput,
-  ) => Effect.Effect<SessionSchema.Info, NotFoundError | MessageNotFoundError | ForkEmptyError>
+  readonly fork: (input: ForkInput) => Effect.Effect<SessionSchema.Info, NotFoundError | MessageNotFoundError>
   readonly get: (sessionID: SessionSchema.ID) => Effect.Effect<SessionSchema.Info, NotFoundError>
   readonly remove: (sessionID: SessionSchema.ID) => Effect.Effect<void, NotFoundError>
   readonly messages: (input: {
@@ -398,33 +395,25 @@ const layer = Layer.effect(
       }),
       fork: Effect.fn("Session.fork")(function* (input) {
         const parent = yield* result.get(input.sessionID)
-        const boundary = yield* db
-          .select({ id: SessionMessageTable.id, seq: SessionMessageTable.seq })
-          .from(SessionMessageTable)
-          .where(
-            and(
-              eq(SessionMessageTable.session_id, input.sessionID),
-              input.boundary.type === "before" ? eq(SessionMessageTable.id, input.boundary.messageID) : undefined,
-            ),
-          )
-          .orderBy(desc(SessionMessageTable.seq))
-          .limit(1)
-          .get()
-          .pipe(Effect.orDie)
-        if (!boundary && input.boundary.type === "before")
-          return yield* new MessageNotFoundError({
-            sessionID: input.sessionID,
-            messageID: input.boundary.messageID,
-          })
-        if (!boundary) return yield* new ForkEmptyError({ sessionID: input.sessionID })
+        const boundary = input.messageID
+          ? yield* db
+              .select({ seq: SessionMessageTable.seq })
+              .from(SessionMessageTable)
+              .where(
+                and(eq(SessionMessageTable.session_id, input.sessionID), eq(SessionMessageTable.id, input.messageID)),
+              )
+              .get()
+              .pipe(Effect.orDie)
+          : undefined
+        if (input.messageID && !boundary)
+          return yield* new MessageNotFoundError({ sessionID: input.sessionID, messageID: input.messageID })
         const sessionID = SessionSchema.ID.create()
-        const instructionThrough =
-          input.boundary.type === "before" ? boundary.seq - 1 : yield* Bus.latestSequence(db, parent.id)
+        const parentSeq = boundary ? boundary.seq - 1 : yield* Bus.latestSequence(db, parent.id)
         yield* bus.publish(SessionEvent.Forked, {
           sessionID,
           parentID: parent.id,
-          boundary: { ...input.boundary, messageID: boundary.id },
-          instructions: yield* InstructionState.valuesAt(db, parent.id, instructionThrough),
+          parentSeq,
+          from: input.messageID,
         })
         return yield* result.get(sessionID).pipe(Effect.orDie)
       }),

packages/core/src/session/error.ts

@@ -10,14 +10,6 @@ export class NotFoundError extends Schema.TaggedErrorClass<NotFoundError>()("Ses
   sessionID: SessionSchema.ID,
 }) {}
 
-export class ForkEmptyError extends Schema.TaggedErrorClass<ForkEmptyError>()("Session.ForkEmptyError", {
-  sessionID: SessionSchema.ID,
-}) {
-  override get message() {
-    return `Cannot fork empty session: ${this.sessionID}`
-  }
-}
-
 export class MessageDecodeError extends Schema.TaggedErrorClass<MessageDecodeError>()("Session.MessageDecodeError", {
   sessionID: SessionSchema.ID,
   messageID: SessionMessage.ID,

packages/core/src/session/info.ts

@@ -8,6 +8,7 @@ import { AbsolutePath, RelativePath } from "../schema"
 import { Workspace } from "../workspace"
 import { SessionSchema } from "./schema"
 import { SessionTable } from "./sql"
+import { SessionMessage } from "./message"
 import { PersistedRevert } from "@opencode-ai/schema/session-revert"
 import { Money } from "@opencode-ai/schema/money"
 
@@ -19,13 +20,12 @@ export function fromRow(row: typeof SessionTable.$inferSelect): SessionSchema.In
     projectID: Project.ID.make(row.project_id),
     title: row.title,
     parentID: row.parent_id ? SessionSchema.ID.make(row.parent_id) : undefined,
-    fork:
-      row.fork_session_id && row.fork_boundary
-        ? {
-            sessionID: SessionSchema.ID.make(row.fork_session_id),
-            boundary: row.fork_boundary,
-          }
-        : undefined,
+    fork: row.fork_session_id
+      ? {
+          sessionID: SessionSchema.ID.make(row.fork_session_id),
+          messageID: row.fork_message_id ? SessionMessage.ID.make(row.fork_message_id) : undefined,
+        }
+      : undefined,
     agent: row.agent ? Agent.ID.make(row.agent) : undefined,
     model: row.model
       ? {

packages/core/src/session/instruction-state.ts

@@ -10,12 +10,11 @@ import { SessionEvent } from "./event"
 import { SessionMessage } from "./message"
 import { Event } from "@opencode-ai/schema/event"
 import { SessionSchema } from "./schema"
-import { InstructionBlobTable, InstructionStateTable } from "./sql"
+import { InstructionBlobTable, InstructionStateTable, SessionTable } from "./sql"
 
 type DatabaseService = Database.Interface["db"]
 
 const decodeInstructionsUpdated = Schema.decodeUnknownSync(SessionEvent.InstructionsUpdated.data)
-const decodeForked = Schema.decodeUnknownSync(SessionEvent.Forked.data)
 
 export interface Observation extends Instructions.Admission {
   readonly sessionID: SessionSchema.ID
@@ -95,26 +94,6 @@ export const apply = Effect.fn("InstructionState.apply")(function* (
     .pipe(Effect.orDie)
 })
 
-export const initialize = Effect.fn("InstructionState.initialize")(function* (
-  db: DatabaseService,
-  sessionID: SessionSchema.ID,
-  seq: number,
-  values: Instructions.Values,
-) {
-  yield* db
-    .insert(InstructionStateTable)
-    .values({
-      session_id: sessionID,
-      epoch_start: seq,
-      through_seq: seq,
-      initial_values: values,
-      current_values: values,
-    })
-    .onConflictDoNothing()
-    .run()
-    .pipe(Effect.orDie)
-})
-
 export const advanceEpoch = Effect.fn("InstructionState.advanceEpoch")(function* (
   db: DatabaseService,
   sessionID: SessionSchema.ID,
@@ -276,14 +255,6 @@ const stateFromEvents = Effect.fnUntraced(function* (db: DatabaseService, sessio
   return folded ? foldedState(sessionID, folded) : undefined
 })
 
-export const valuesAt = Effect.fn("InstructionState.valuesAt")(function* (
-  db: DatabaseService,
-  sessionID: SessionSchema.ID,
-  through: number,
-) {
-  return fold(yield* instructionEvents(db, sessionID, through))?.current
-})
-
 const latestRelevantSequence = Effect.fnUntraced(function* (db: DatabaseService, sessionID: SessionSchema.ID) {
   return yield* db
     .select({ seq: EventTable.seq })
@@ -353,23 +324,15 @@ const revertedEventType = Bus.versionedType(
   SessionEvent.RevertEvent.Committed.type,
   SessionEvent.RevertEvent.Committed.durable.version,
 )
-const forkedEventType = Bus.versionedType(SessionEvent.Forked.type, SessionEvent.Forked.durable.version)
-const relevantEventTypes = [
-  forkedEventType,
-  instructionEventType,
-  compactionEventType,
-  movedEventType,
-  revertedEventType,
-]
+const relevantEventTypes = [instructionEventType, compactionEventType, movedEventType, revertedEventType]
 
 type InstructionEventRow = typeof EventTable.$inferSelect
 
 const instructionEvents = Effect.fnUntraced(function* (
   db: DatabaseService,
   sessionID: SessionSchema.ID,
-  through?: number,
 ): Effect.fn.Return<ReadonlyArray<InstructionEventRow>> {
-  return yield* eventRows(db, sessionID, relevantEventTypes, undefined, through)
+  return yield* eventRows(db, sessionID, relevantEventTypes)
 })
 
 const instructionUpdatesAfter = Effect.fnUntraced(function* (
@@ -385,22 +348,48 @@ const eventRows = Effect.fnUntraced(function* (
   sessionID: SessionSchema.ID,
   types: ReadonlyArray<string>,
   after?: number,
-  through?: number,
 ): Effect.fn.Return<ReadonlyArray<InstructionEventRow>> {
-  return yield* db
-    .select()
-    .from(EventTable)
-    .where(
-      and(
-        eq(EventTable.aggregate_id, sessionID),
-        inArray(EventTable.type, types),
-        after === undefined ? undefined : gt(EventTable.seq, after),
-        through === undefined ? undefined : lte(EventTable.seq, through),
-      ),
-    )
-    .orderBy(asc(EventTable.seq))
-    .all()
+  const segments = (yield* lineage(db, sessionID)).filter(
+    (segment) => after === undefined || segment.through === undefined || segment.through > after,
+  )
+  return (yield* Effect.forEach(segments, (segment) =>
+    db
+      .select()
+      .from(EventTable)
+      .where(
+        and(
+          eq(EventTable.aggregate_id, segment.sessionID),
+          inArray(EventTable.type, types),
+          segment.through === undefined ? undefined : lte(EventTable.seq, segment.through),
+          after === undefined ? undefined : gt(EventTable.seq, after),
+        ),
+      )
+      .orderBy(asc(EventTable.seq))
+      .all()
+      .pipe(Effect.orDie),
+  )).flat()
+})
+
+const lineage = Effect.fnUntraced(function* (
+  db: DatabaseService,
+  sessionID: SessionSchema.ID,
+  through?: number,
+): Effect.fn.Return<ReadonlyArray<{ readonly sessionID: SessionSchema.ID; readonly through?: number }>> {
+  const session = yield* db
+    .select({ parentID: SessionTable.fork_session_id, forkSeq: SessionTable.fork_seq })
+    .from(SessionTable)
+    .where(eq(SessionTable.id, sessionID))
+    .get()
     .pipe(Effect.orDie)
+  const inherited =
+    session?.parentID && session.forkSeq !== null
+      ? yield* lineage(
+          db,
+          session.parentID,
+          through === undefined ? session.forkSeq : Math.min(session.forkSeq, through),
+        )
+      : []
+  return [...inherited, { sessionID, ...(through === undefined ? {} : { through }) }]
 })
 
 function fold(rows: ReadonlyArray<InstructionEventRow>) {
@@ -413,12 +402,6 @@ function fold(rows: ReadonlyArray<InstructionEventRow>) {
       }
     | undefined
   >((state, row) => {
-    if (row.type === forkedEventType) {
-      const instructions = decodeForked(row.data).instructions
-      return instructions
-        ? { epochStart: row.seq, throughSeq: row.seq, initial: instructions, current: instructions }
-        : undefined
-    }
     if (row.type === movedEventType || row.type === revertedEventType) return undefined
     if (row.type === compactionEventType)
       return state

packages/core/src/session/pending.ts

@@ -53,6 +53,7 @@ export class LifecycleConflict extends Schema.TaggedErrorClass<LifecycleConflict
 
 const fromRow = (row: typeof SessionPendingTable.$inferSelect): Info => {
   const base = {
+    admittedSeq: row.admitted_seq,
     id: SessionMessage.ID.make(row.id),
     sessionID: SessionSchema.ID.make(row.session_id),
     timeCreated: DateTime.makeUnsafe(row.time_created),
@@ -133,6 +134,7 @@ const promotedFromHistory = Effect.fn("SessionPending.promotedFromHistory")(func
     const decoded = decodeAdmittedEvent(row.data)
     if (decoded._tag !== "Some" || decoded.value.inputID !== id) continue
     const base = {
+      admittedSeq: row.seq,
       id,
       sessionID,
       timeCreated: DateTime.makeUnsafe(row.created),
@@ -170,7 +172,10 @@ export const admit = Effect.fn("SessionPending.admit")(function* (
     })
     .pipe(
       Effect.flatMap((event) => {
+        if (event.durable === undefined)
+          return Effect.die(new Error("Session input admission event is missing aggregate sequence"))
         const base = {
+          admittedSeq: event.durable.seq,
           id: request.id,
           sessionID: request.sessionID,
           timeCreated: event.created,

packages/core/src/session/projector.ts

@@ -1,6 +1,6 @@
 export * as SessionProjector from "./projector"
 
-import { and, asc, desc, eq, gt, gte, inArray, lt, lte, sql } from "drizzle-orm"
+import { and, asc, desc, eq, gt, gte, inArray, lt, sql } from "drizzle-orm"
 import { DateTime, Effect, Layer, Schema, Stream } from "effect"
 import { Database } from "../database/database"
 import { Bus } from "../bus"
@@ -174,28 +174,25 @@ const projectFork = Effect.fn("SessionProjector.projectFork")(function* (
     .get()
     .pipe(Effect.orDie)
   if (!parent) return yield* Effect.die(new Error(`Fork parent session not found: ${event.data.parentID}`))
-  const boundary = yield* db
-    .select({ seq: SessionMessageTable.seq })
-    .from(SessionMessageTable)
-    .where(
-      and(
-        eq(SessionMessageTable.session_id, event.data.parentID),
-        eq(SessionMessageTable.id, event.data.boundary.messageID),
-      ),
-    )
-    .get()
-    .pipe(Effect.orDie)
-  if (!boundary)
-    return yield* Effect.die(new Error(`Fork boundary message not found: ${event.data.boundary.messageID}`))
+  const boundary = event.data.from
+    ? yield* db
+        .select({ seq: SessionMessageTable.seq })
+        .from(SessionMessageTable)
+        .where(
+          and(eq(SessionMessageTable.session_id, event.data.parentID), eq(SessionMessageTable.id, event.data.from)),
+        )
+        .get()
+        .pipe(Effect.orDie)
+    : undefined
+  if (event.data.from && !boundary)
+    return yield* Effect.die(new Error(`Fork boundary message not found: ${event.data.from}`))
   const copied = yield* db
     .select({ seq: SessionMessageTable.seq })
     .from(SessionMessageTable)
     .where(
       and(
         eq(SessionMessageTable.session_id, event.data.parentID),
-        event.data.boundary.type === "before"
-          ? lt(SessionMessageTable.seq, boundary.seq)
-          : lte(SessionMessageTable.seq, boundary.seq),
+        boundary === undefined ? undefined : lt(SessionMessageTable.seq, boundary.seq),
       ),
     )
     .orderBy(desc(SessionMessageTable.seq))
@@ -210,7 +207,8 @@ const projectFork = Effect.fn("SessionProjector.projectFork")(function* (
       id: event.data.sessionID,
       parent_id: null,
       fork_session_id: event.data.parentID,
-      fork_boundary: event.data.boundary,
+      fork_message_id: event.data.from,
+      fork_seq: event.data.parentSeq,
       project_id: parent.project_id,
       workspace_id: parent.workspace_id,
       slug: Slug.create(),
@@ -316,9 +314,8 @@ const projectFork = Effect.fn("SessionProjector.projectFork")(function* (
 
     cursor = rows.at(-1)!.seq
   }
-  if (copiedSeq !== undefined) yield* Bus.reserveSequence(db, event.data.sessionID, copiedSeq)
-  if (event.data.instructions)
-    yield* InstructionState.initialize(db, event.data.sessionID, event.durable.seq, event.data.instructions)
+  yield* Bus.reserveSequence(db, event.data.sessionID, event.data.parentSeq)
+  yield* InstructionState.rebuild(db, event.data.sessionID)
 })
 
 function run(db: DatabaseService, event: MessageEvent) {

packages/core/src/session/sql.ts

@@ -32,7 +32,8 @@ export const SessionTable = sqliteTable(
     workspace_id: text().$type<Workspace.ID>(),
     parent_id: text().$type<SessionSchema.ID>(),
     fork_session_id: text().$type<SessionSchema.ID>(),
-    fork_boundary: text({ mode: "json" }).$type<Session.ForkBoundary>(),
+    fork_message_id: text().$type<SessionMessage.ID>(),
+    fork_seq: integer(),
     slug: text().notNull(),
     directory: directoryColumn().notNull(),
     path: pathColumn(),

packages/core/src/shell/select.ts

@@ -173,7 +173,7 @@ export function args(file: string, command: string) {
   if (n === "nu" || n === "fish") return ["-c", command]
   if (n === "zsh" || n === "bash") return ["-c", command]
   if (n === "cmd") return ["/c", command]
-  if (ps(file)) return ["-NoLogo", "-NoProfile", "-NonInteractive", "-Command", command]
+  if (ps(file)) return ["-NoProfile", "-Command", command]
   return ["-c", command]
 }
 

packages/core/src/tool/plugin/shell.ts

@@ -1,5 +1,6 @@
 export * as ShellTool from "./shell"
 
+import path from "path"
 import { ToolFailure } from "@opencode-ai/ai"
 import type { Content } from "@opencode-ai/schema/tool"
 import type { Context as PluginContext } from "@opencode-ai/plugin/effect/plugin"
@@ -65,14 +66,18 @@ const Output = Schema.Struct({
   ...StructuredOutput.fields,
   output: Schema.String,
   status: Schema.optionalKey(Schema.Literals(["completed", "running"])),
+  warnings: Schema.optionalKey(Schema.Array(Schema.String)),
 })
 
 type Output = typeof Output.Type
 
 const modelOutput = (output: Output): string | undefined => {
-  if (output.status === "running") return BACKGROUND_INSTRUCTION
-  if (output.timeout) return "Command timed out before completion."
-  return `Command exited with code ${output.exit}.`
+  const warnings = output.warnings?.length
+    ? `\n\nWarnings:\n${output.warnings.map((warning) => `- ${warning}`).join("\n")}`
+    : ""
+  if (output.status === "running") return `${warnings.trimStart()}${warnings ? "\n\n" : ""}${BACKGROUND_INSTRUCTION}`
+  if (output.timeout) return `${warnings.trimStart()}${warnings ? "\n\n" : ""}Command timed out before completion.`
+  return `${warnings.trimStart()}${warnings ? "\n\n" : ""}Command exited with code ${output.exit}.`
 }
 
 /**
@@ -81,12 +86,31 @@ const modelOutput = (output: Output): string | undefined => {
  */
 // TODO: Port tree-sitter bash / PowerShell parser-based approval reduction.
 // TODO: Port BashArity reusable command-prefix approvals.
+// TODO: Replace token-based command-argument external-directory advisories with parser-based detection.
 // TODO: Add plugin shell.env environment augmentation once plugin hooks exist.
 // TODO: Persist job status and define restart recovery before exposing remote observation.
 // TODO: Add HTTP job observation only after durable status, restart recovery, and authorization are defined.
 // TODO: Revisit process-group cleanup and platform coverage with shell-specific tests if current AppProcess semantics do not fully cover it.
 // TODO: Revisit binary output handling if stdout/stderr decoding is text-only.
 
+const shellTokens = (command: string) => command.match(/(?:[^\s"']+|"[^"]*"|'[^']*')+/g) ?? []
+const unquote = (value: string) => value.replace(/^(['"])(.*)\1$/, "$2")
+const externalCommandDirectories = Effect.fn("ShellTool.externalCommandDirectories")(function* (
+  fs: FSUtil.Interface,
+  command: string,
+  cwd: string,
+) {
+  const directories = new Set<string>()
+  for (const token of shellTokens(command)) {
+    const value = unquote(token).replace(/[;,|&]+$/, "")
+    if (!path.isAbsolute(value)) continue
+    const resolved = yield* fs.resolve(value)
+    if (FSUtil.contains(cwd, resolved)) continue
+    directories.add(yield* fs.resolve(path.dirname(resolved)))
+  }
+  return [...directories]
+})
+
 export const Plugin = {
   id: "opencode.tool.shell",
   effect: Effect.fn("ShellTool.Plugin")(function* (ctx: PluginContext) {
@@ -155,6 +179,10 @@ export const Plugin = {
                     agent: context.agent,
                     source,
                   })
+                const warnings = (yield* externalCommandDirectories(fsUtil, input.command, target.canonical)).map(
+                  (directory) =>
+                    `Command argument references external directory ${path.join(directory, "*").replaceAll("\\", "/")}. Shell runs with host-user filesystem, process, and network authority; this scan is advisory only.`,
+                )
                 yield* permission.assert({
                   action: name,
                   resources: [input.command],
@@ -236,6 +264,7 @@ export const Plugin = {
                     shellID: info.id,
                     truncated: false,
                     status: "running" as const,
+                    ...(warnings.length ? { warnings } : {}),
                   }
                 }
 
@@ -250,13 +279,14 @@ export const Plugin = {
                     shellID: info.id,
                     truncated: false,
                     status: "running" as const,
+                    ...(warnings.length ? { warnings } : {}),
                   }
                 }
                 if (result?.info.status === "error")
                   return yield* Effect.fail(new Error(result.info.error ?? "Command failed"))
                 if (result?.info.status === "cancelled") return yield* Effect.fail(new Error("Command cancelled"))
 
-                return yield* Deferred.await(settled)
+                return { ...(yield* Deferred.await(settled)), ...(warnings.length ? { warnings } : {}) }
               }).pipe(
                 Effect.map((output) => {
                   const content: Array<Content> = [{ type: "text", text: output.output }]