fix(ai): support streams without finish reasons

packages/ai/src/protocols/openai-chat.ts

@@ -241,6 +241,8 @@ export interface ParserState {
   readonly reasoningEmitted: boolean
   readonly latestToolIndex?: number
   readonly nextToolIndex: number
+  readonly outputStarted: boolean
+  readonly requireFinishReason: boolean
 }
 
 // =============================================================================
@@ -707,9 +709,7 @@ const step = (state: ParserState, event: OpenAIChatEvent) =>
       Boolean(delta?.content) ||
       reasoning !== undefined ||
       (Array.isArray(delta?.reasoning_details) && delta.reasoning_details.length > 0) ||
-      toolDeltas.some(
-        (tool) => Boolean(tool.id) || Boolean(tool.function?.name) || Boolean(tool.function?.arguments),
-      )
+      toolDeltas.some((tool) => Boolean(tool.id) || Boolean(tool.function?.name) || Boolean(tool.function?.arguments))
     if (state.finishReason !== undefined) {
       if (hasLateContent)
         return yield* ProviderShared.eventError(ADAPTER, "OpenAI Chat received content after the finish reason")
@@ -749,8 +749,7 @@ const step = (state: ParserState, event: OpenAIChatEvent) =>
       const fallback = toolDeltas.length > 1 ? position : (latestToolIndex ?? position)
       const fallbackTool = tools[fallback] ?? pendingTools[fallback]
       const index =
-        tool.index ?? matched ??
-        (tool.id && fallbackTool?.id && fallbackTool.id !== tool.id ? nextToolIndex : fallback)
+        tool.index ?? matched ?? (tool.id && fallbackTool?.id && fallbackTool.id !== tool.id ? nextToolIndex : fallback)
       const current = tools[index]
       const pending = pendingTools[index]
       const id = current?.id ?? pending?.id ?? (tool.id || undefined)
@@ -806,6 +805,8 @@ const step = (state: ParserState, event: OpenAIChatEvent) =>
         reasoningEmitted,
         latestToolIndex,
         nextToolIndex,
+        outputStarted: state.outputStarted || hasLateContent,
+        requireFinishReason: state.requireFinishReason,
       },
       events,
     ] as const
@@ -836,6 +837,23 @@ const finishEvents = (state: ParserState): ReadonlyArray<LLMEvent> => {
   return events
 }
 
+const onHalt = (state: ParserState) =>
+  Effect.gen(function* () {
+    if (state.finishReason !== undefined || state.requireFinishReason) return finishEvents(state)
+    if (!state.outputStarted) return []
+    if (Object.keys(state.pendingTools).length > 0)
+      return yield* ProviderShared.eventError(ADAPTER, "OpenAI Chat tool call delta is missing id or name")
+    // Chat has no per-call stop event, so an accepted EOF must finalize every
+    // accumulated tool input before publishing the synthetic terminal reason.
+    const finished = yield* ToolStream.finishAll(ADAPTER, state.tools)
+    return finishEvents({
+      ...state,
+      tools: finished.tools,
+      toolCallEvents: finished.events,
+      finishReason: { normalized: "unknown" },
+    })
+  })
+
 // =============================================================================
 // Protocol And OpenAI Route
 // =============================================================================
@@ -863,9 +881,11 @@ export const protocol = Protocol.make({
       reasoningDetailsObserved: false,
       reasoningEmitted: false,
       nextToolIndex: 0,
+      outputStarted: false,
+      requireFinishReason: request.model.compatibility?.requireFinishReason ?? true,
     }),
     step,
-    onHalt: finishEvents,
+    onHalt,
   },
 })
 

packages/ai/src/route/client.ts

@@ -7,7 +7,7 @@ import { Framing } from "./framing"
 import { HttpTransport } from "./transport"
 import type { HttpMiddleware, Transport, TransportRuntime } from "./transport"
 import { WebSocketExecutor } from "./transport"
-import type { Protocol } from "./protocol"
+import type { Protocol, ProtocolStream } from "./protocol"
 import { applyCachePolicy } from "../cache-policy"
 import * as ProviderShared from "../protocols/shared"
 import type { ProtocolID, ProviderOptions } from "../schema"
@@ -243,28 +243,56 @@ const incompleteStreamError = (route: string) =>
     }),
   })
 
-const requireTerminalEvent = (route: string) => (events: Stream.Stream<LLMEvent, AIError>) =>
+const ensureTerminalEvent = (route: string, required: boolean) => (events: Stream.Stream<LLMEvent, AIError>) =>
   Stream.suspend(() => {
     let terminal = false
+    let output = false
+    const fallback = Stream.suspend(() => {
+      if (terminal) return Stream.empty
+      if (required || !output) return Stream.fail(incompleteStreamError(route))
+      // The compatibility override trusts a clean stream end, but it cannot
+      // recover the provider's omitted reason.
+      const reason = { normalized: "unknown" as const }
+      return Stream.make(LLMEvent.stepFinish({ index: 0, reason }), LLMEvent.finish({ reason }))
+    })
     return events.pipe(
       Stream.mapEffect((event) => {
         if (terminal)
           return Effect.fail(
             ProviderShared.eventError(route, `Provider emitted ${event.type} after the terminal event`),
           )
+        output = true
         if (LLMEvent.is.finish(event) || LLMEvent.is.providerError(event)) terminal = true
         return Effect.succeed(event)
       }),
-      Stream.onEnd(
-        Effect.suspend(() =>
-          terminal
-            ? Effect.void
-            : Effect.fail(incompleteStreamError(route)),
-        ),
-      ),
+      Stream.concat(fallback),
     )
   })
 
+type ProtocolEvent<Event> = { readonly type: "event"; readonly event: Event } | { readonly type: "halt" }
+
+const parseProtocolEvents = <Event, State>(
+  events: Stream.Stream<Event, AIError>,
+  request: LLMRequest,
+  protocol: { readonly stream: ProtocolStream<unknown, Event, State> },
+) =>
+  events.pipe(
+    Stream.map((event): ProtocolEvent<Event> => ({ type: "event", event })),
+    // A normal halt becomes an in-band parser input so finalization may fail.
+    Stream.concat(Stream.succeed({ type: "halt" } as const)),
+    Stream.mapAccumEffect(
+      () => protocol.stream.initial(request),
+      (state, event) => {
+        if (event.type === "event") return protocol.stream.step(state, event.event)
+        if (!protocol.stream.onHalt) return Effect.succeed([state, []] as const)
+        const events = protocol.stream.onHalt(state)
+        return Effect.isEffect(events)
+          ? events.pipe(Effect.map((events) => [state, events] as const))
+          : Effect.succeed([state, events] as const)
+      },
+    ),
+  )
+
 function makeFromTransport<Body, Prepared, Frame, Event, State>(
   input: MakeTransportInput<Body, Prepared, Frame, Event, State>,
 ): Route<Body, Prepared> {
@@ -329,14 +357,9 @@ function makeFromTransport<Body, Prepared, Frame, Event, State>(
             Stream.mapEffect(decodeEvent(route)),
             protocol.stream.terminal ? Stream.takeUntil(protocol.stream.terminal) : (stream) => stream,
           )
-        return events.pipe(
-          Stream.mapAccumEffect(
-            () => protocol.stream.initial(request),
-            protocol.stream.step,
-            protocol.stream.onHalt ? { onHalt: protocol.stream.onHalt } : undefined,
-          ),
+        return parseProtocolEvents(events, request, protocol).pipe(
           Stream.catchCause((cause) => Stream.fail(streamError(route, `Failed to read ${route} stream`, cause))),
-          requireTerminalEvent(route),
+          ensureTerminalEvent(route, request.model.compatibility?.requireFinishReason ?? true),
         )
       },
     } satisfies Route<Body, Prepared>

packages/ai/src/route/protocol.ts

@@ -59,8 +59,8 @@ export interface ProtocolStream<Frame, Event, State> {
   readonly step: (state: State, event: Event) => Effect.Effect<readonly [State, ReadonlyArray<LLMEvent>], AIError>
   /** Optional request-completion signal for transports that do not end naturally. */
   readonly terminal?: (event: Event) => boolean
-  /** Optional flush emitted when the framed stream ends. */
-  readonly onHalt?: (state: State) => ReadonlyArray<LLMEvent>
+  /** Optional flush emitted when the framed stream ends successfully. */
+  readonly onHalt?: (state: State) => ReadonlyArray<LLMEvent> | Effect.Effect<ReadonlyArray<LLMEvent>, AIError>
 }
 
 /**

packages/ai/test/adapter.test.ts

@@ -138,6 +138,29 @@ describe("llm route", () => {
     }),
   )
 
+  unterminated.effect("synthesizes an unknown finish when a terminal event is not required", () =>
+    Effect.gen(function* () {
+      const response = yield* (yield* LLMClient.Service).generate(
+        LLMRequest.update(request, {
+          model: updateModel(request.model, { compatibility: { requireFinishReason: false } }),
+        }),
+      )
+
+      expect(response.text).toBe("partial")
+      expect(response.finishReason).toEqual({ normalized: "unknown" })
+      expect(response.events.slice(-2)).toEqual([
+        {
+          type: "step-finish",
+          index: 0,
+          reason: { normalized: "unknown" },
+          usage: undefined,
+          providerMetadata: undefined,
+        },
+        { type: "finish", reason: { normalized: "unknown" }, usage: undefined },
+      ])
+    }),
+  )
+
   it.effect("selects routes by model route value", () =>
     Effect.gen(function* () {
       const prepared = yield* compileRequest(

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

@@ -40,6 +40,10 @@ const request = LLM.request({
   generation: { maxTokens: 20, temperature: 0 },
 })
 
+const optionalFinishRequest = LLMRequest.update(request, {
+  model: LanguageModel.update(model, { compatibility: { requireFinishReason: false } }),
+})
+
 describe("OpenAI Chat route", () => {
   it.effect("prepares OpenAI Chat payload", () =>
     Effect.gen(function* () {
@@ -596,6 +600,20 @@ describe("OpenAI Chat route", () => {
     }),
   )
 
+  it.effect("accepts text and usage without a finish reason when configured", () =>
+    Effect.gen(function* () {
+      const body = sseEvents(
+        deltaChunk({ role: "assistant", content: "Hello" }),
+        usageChunk({ prompt_tokens: 5, completion_tokens: 1, total_tokens: 6 }),
+      )
+      const response = yield* LLMClient.generate(optionalFinishRequest).pipe(Effect.provide(fixedResponse(body)))
+
+      expect(response.text).toBe("Hello")
+      expect(response.finishReason).toEqual({ normalized: "unknown" })
+      expect(response.usage).toMatchObject({ inputTokens: 5, outputTokens: 1, totalTokens: 6 })
+    }),
+  )
+
   it.effect("parses and replays OpenAI-compatible reasoning fields", () =>
     Effect.gen(function* () {
       const fields = ["reasoning_content", "reasoning", "reasoning_text"] as const
@@ -1145,21 +1163,89 @@ describe("OpenAI Chat route", () => {
     }),
   )
 
-  it.effect("fails on malformed stream events", () =>
+  it.effect("finalizes a streamed tool call without a finish reason when configured", () =>
+    Effect.gen(function* () {
+      const body = sseEvents(
+        deltaChunk({
+          role: "assistant",
+          tool_calls: [{ index: 0, id: "call_1", function: { name: "lookup", arguments: '{"query"' } }],
+        }),
+        deltaChunk({ tool_calls: [{ index: 0, function: { arguments: ':"weather"}' } }] }),
+      )
+      const response = yield* LLMClient.generate(
+        LLMRequest.update(optionalFinishRequest, {
+          tools: [ToolDefinition.make({ name: "lookup", description: "Lookup data", inputSchema: { type: "object" } })],
+        }),
+      ).pipe(Effect.provide(fixedResponse(body)))
+
+      expect(response.toolCalls).toMatchObject([{ id: "call_1", name: "lookup", input: { query: "weather" } }])
+      expect(response.finishReason).toEqual({ normalized: "unknown" })
+    }),
+  )
+
+  it.effect("settles malformed tool input without a finish reason when configured", () =>
+    Effect.gen(function* () {
+      const body = sseEvents(
+        deltaChunk({
+          role: "assistant",
+          tool_calls: [{ index: 0, id: "call_1", function: { name: "lookup", arguments: '{"query"' } }],
+        }),
+      )
+      const response = yield* LLMClient.generate(
+        LLMRequest.update(optionalFinishRequest, {
+          tools: [ToolDefinition.make({ name: "lookup", description: "Lookup data", inputSchema: { type: "object" } })],
+        }),
+      ).pipe(Effect.provide(fixedResponse(body)))
+
+      expect(response.events.filter(LLMEvent.is.toolInputError)).toMatchObject([
+        { id: "call_1", name: "lookup", raw: '{"query"' },
+      ])
+      expect(response.toolCalls).toEqual([])
+      expect(response.finishReason).toEqual({ normalized: "unknown" })
+    }),
+  )
+
+  it.effect("rejects incomplete tool identity without a finish reason when configured", () =>
+    Effect.gen(function* () {
+      const body = sseEvents(deltaChunk({ tool_calls: [{ index: 0, id: "call_1", function: { arguments: "{}" } }] }))
+      const error = yield* LLMClient.generate(optionalFinishRequest).pipe(
+        Effect.provide(fixedResponse(body)),
+        Effect.flip,
+      )
+
+      expect(error.message).toContain("OpenAI Chat tool call delta is missing id or name")
+    }),
+  )
+
+  it.effect("rejects an empty stream when a finish reason is not required", () =>
+    Effect.gen(function* () {
+      const error = yield* LLMClient.generate(optionalFinishRequest).pipe(
+        Effect.provide(fixedResponse(sseEvents())),
+        Effect.flip,
+      )
+
+      expect(error.reason).toMatchObject({ _tag: "InvalidProviderOutput", classification: "incomplete-stream" })
+    }),
+  )
+
+  it.effect("fails on malformed stream events when a finish reason is not required", () =>
     Effect.gen(function* () {
       const body = sseEvents(deltaChunk({ content: 123 }))
-      const error = yield* LLMClient.generate(request).pipe(Effect.provide(fixedResponse(body)), Effect.flip)
+      const error = yield* LLMClient.generate(optionalFinishRequest).pipe(
+        Effect.provide(fixedResponse(body)),
+        Effect.flip,
+      )
 
       expect(error.message).toContain("Invalid openai/openai-chat stream event")
     }),
   )
 
-  it.effect("surfaces transport errors that occur mid-stream", () =>
+  it.effect("surfaces transport errors when a finish reason is not required", () =>
     Effect.gen(function* () {
       const layer = truncatedStream([
         `data: ${JSON.stringify(deltaChunk({ role: "assistant", content: "Hello" }))}\n\n`,
       ])
-      const error = yield* LLMClient.generate(request).pipe(Effect.provide(layer), Effect.flip)
+      const error = yield* LLMClient.generate(optionalFinishRequest).pipe(Effect.provide(layer), Effect.flip)
 
       expect(error.message).toContain("Failed to read openai/openai-chat stream")
     }),

packages/core/src/config/normalize.ts

@@ -41,7 +41,7 @@ export type Result =
   | { readonly type: "rejected"; readonly diagnostics: readonly Diagnostic[] }
 
 const options = { errors: "all", onExcessProperty: "ignore", propertyOrder: "original" } as const
-const unsupportedTopLevel = ["logLevel", "server", "subagent_depth", "layout"] as const
+const unsupportedTopLevel = ["logLevel", "server", "small_model", "subagent_depth", "layout"] as const
 const unsupportedExperimental = [
   "disable_paste_summary",
   "batch_tool",
@@ -113,23 +113,6 @@ export function normalize(input: unknown): Result {
   const legacyAgents = mapValues(decodeMap(input.agent, ConfigAgentV1.Info, ["agent"], diagnostics), (value) =>
     canonical(ConfigAgent.Info, ConfigMigrateV1.migrateAgent(value)),
   )
-  const legacySmallModel = own(input, "small_model")
-    ? decodeValue(Schema.String, input.small_model, ["small_model"], diagnostics)
-    : undefined
-  const migratedSmallModel = legacySmallModel
-    ? ConfigMigrateV1.migrate({ small_model: legacySmallModel }).agents?.title?.model
-    : undefined
-  if (legacySmallModel && !migratedSmallModel)
-    diagnostics.push({
-      kind: "unsupported",
-      path: ["small_model"],
-      message: "omitted unsupported legacy model reference",
-    })
-  if (migratedSmallModel)
-    legacyAgents.title = {
-      model: migratedSmallModel,
-      ...legacyAgents.title,
-    }
   const modeAgents = mapValues(decodeMap(input.mode, ConfigAgentV1.Info, ["mode"], diagnostics), (value) =>
     canonical(ConfigAgent.Info, ConfigMigrateV1.migrateAgent({ ...value, mode: "primary" })),
   )

packages/core/src/file-mutation.ts

@@ -7,7 +7,7 @@ import { FSUtil } from "@opencode-ai/util/fs-util"
 import { Bom } from "@opencode-ai/util/bom"
 
 export interface Target {
-  readonly absolute: string
+  readonly canonical: string
   readonly resource: string
 }
 
@@ -37,7 +37,7 @@ export interface Interface {
 export class Service extends Context.Service<Service, Interface>()("@opencode/FileMutation") {}
 
 /**
- * Serialize file changes by absolute target. Conditional writes compare and
+ * Serialize file changes by canonical target. Conditional writes compare and
  * write under the same process-local lock so cooperating OpenCode mutations do
  * not overwrite changes made from the same stale content.
  */
@@ -49,11 +49,11 @@ const layer = Layer.effect(
     const withTargetLock =
       (target: Target) =>
       <A, E, R>(effect: Effect.Effect<A, E, R>) =>
-        locks.withLock(target.absolute)(Effect.uninterruptible(effect))
+        locks.withLock(target.canonical)(Effect.uninterruptible(effect))
 
     const writeResult = (target: Target, existed: boolean): WriteResult => ({
       operation: "write",
-      target: target.absolute,
+      target: target.canonical,
       resource: target.resource,
       existed,
     })
@@ -61,8 +61,8 @@ const layer = Layer.effect(
     const write = Effect.fn("FileMutation.write")((input: WriteInput) =>
       withTargetLock(input.target)(
         Effect.gen(function* () {
-          const existed = yield* fs.exists(input.target.absolute)
-          yield* fs.writeWithDirs(input.target.absolute, input.content)
+          const existed = yield* fs.exists(input.target.canonical)
+          yield* fs.writeWithDirs(input.target.canonical, input.content)
           return writeResult(input.target, existed)
         }),
       ),
@@ -73,10 +73,10 @@ const layer = Layer.effect(
         Effect.gen(function* () {
           const next = Bom.split(input.content)
           const current = yield* fs
-            .readFile(input.target.absolute)
+            .readFile(input.target.canonical)
             .pipe(Effect.catchReason("PlatformError", "NotFound", () => Effect.succeed(undefined)))
           yield* fs.writeWithDirs(
-            input.target.absolute,
+            input.target.canonical,
             Bom.join(next.text, Boolean(current && Bom.has(current)) || next.bom),
           )
           return writeResult(input.target, current !== undefined)

packages/core/src/location-mutation.ts

@@ -23,9 +23,14 @@ export const ResolveInput = Schema.Struct({
 })
 export type ResolveInput = typeof ResolveInput.Type
 
+export class PathError extends Schema.TaggedErrorClass<PathError>()("LocationMutation.PathError", {
+  path: Schema.String,
+  reason: Schema.Literal("non_directory_ancestor"),
+}) {}
+
 export interface ExternalDirectoryAuthorization {
   readonly action: "external_directory"
-  /** Lexical directory used as the external approval boundary. */
+  /** Canonical existing directory used as the external approval boundary. */
   readonly directory: string
   /** `external_directory` permission resource. */
   readonly resource: string
@@ -39,9 +44,9 @@ export const externalDirectoryPermission = (input: ExternalDirectoryAuthorizatio
 })
 
 export interface Target {
-  /** Absolute lexical path. */
-  readonly absolute: string
-  /** Permission resource: Location-relative for internal paths, absolute for external paths. */
+  /** Canonical existing path, or missing path below a canonical directory. */
+  readonly canonical: string
+  /** Permission resource: Location-relative for internal paths, canonical for external paths. */
   readonly resource: string
   readonly externalDirectory?: ExternalDirectoryAuthorization
 }
@@ -52,11 +57,25 @@ export interface Interface {
    * from the Location. Paths outside it require separate `external_directory`
    * approval. This does not approve the mutation.
    */
-  readonly resolve: (input: ResolveInput) => Effect.Effect<Target, FSUtil.Error>
+  readonly resolve: (input: ResolveInput) => Effect.Effect<Target, PathError | FSUtil.Error>
 }
 
 export class Service extends Context.Service<Service, Interface>()("@opencode/LocationMutation") {}
 
+interface ResolvedPath {
+  readonly canonical: string
+  readonly type?:
+    | "File"
+    | "Directory"
+    | "SymbolicLink"
+    | "BlockDevice"
+    | "CharacterDevice"
+    | "FIFO"
+    | "Socket"
+    | "Unknown"
+  readonly directory: string
+}
+
 const slash = (value: string) => value.replaceAll("\\", "/")
 
 const layer = Layer.effect(
@@ -65,33 +84,65 @@ const layer = Layer.effect(
     const fs = yield* FSUtil.Service
     const location = yield* Location.Service
 
+    function notFound<A>(effect: Effect.Effect<A, FSUtil.Error>) {
+      return effect.pipe(Effect.catchReason("PlatformError", "NotFound", () => Effect.succeed(undefined)))
+    }
+
+    const resolvePath = Effect.fnUntraced(function* (absolute: string) {
+      const existing = yield* notFound(fs.realPath(absolute))
+      if (existing !== undefined) {
+        const info = yield* fs.stat(existing)
+        return {
+          canonical: existing,
+          type: info.type,
+          directory: info.type === "Directory" ? existing : path.dirname(existing),
+        } satisfies ResolvedPath
+      }
+
+      let anchor = path.dirname(absolute)
+      while (true) {
+        const canonical = yield* notFound(fs.realPath(anchor))
+        if (canonical !== undefined) {
+          const info = yield* fs.stat(canonical)
+          if (info.type !== "Directory") {
+            return yield* new PathError({ path: absolute, reason: "non_directory_ancestor" })
+          }
+          return {
+            canonical: path.resolve(canonical, path.relative(anchor, absolute)),
+            directory: canonical,
+          } satisfies ResolvedPath
+        }
+        const parent = path.dirname(anchor)
+        if (parent === anchor) return yield* new PathError({ path: absolute, reason: "non_directory_ancestor" })
+        anchor = parent
+      }
+    })
+
     const resolve = Effect.fn("LocationMutation.resolve")(function* (input: ResolveInput) {
       const absolute = path.resolve(location.directory, input.path)
-      if (FSUtil.contains(location.directory, absolute)) {
-        return {
-          absolute,
-          resource: slash(path.relative(location.directory, absolute) || "."),
-        } satisfies Target
-      }
-      const type =
-        input.kind === "directory"
-          ? "Directory"
-          : (yield* fs
-              .stat(absolute)
-              .pipe(Effect.catchReason("PlatformError", "NotFound", () => Effect.succeed(undefined))))?.type
-      const externalDirectory = type === "Directory" ? absolute : path.dirname(absolute)
+      // External access follows the requested path boundary. Symlinks reached through an
+      // internal path intentionally retain internal permission semantics after canonicalization.
+      const lexicallyInternal = FSUtil.contains(location.directory, absolute)
+
+      const resolved = yield* resolvePath(absolute)
+      const external = !lexicallyInternal
+      const resource = external ? slash(resolved.canonical) : slash(path.relative(location.directory, absolute) || ".")
+      const externalDirectory =
+        input.kind === "directory" && resolved.type === "Directory" ? resolved.canonical : resolved.directory
       const externalResource = slash(path.join(externalDirectory, "*"))
       return {
-        absolute,
-        resource: slash(absolute),
-        externalDirectory: {
-          action: "external_directory",
-          directory: externalDirectory,
-          resource: externalResource,
-          save: slash(
-            path.join((yield* Project.root(fs, AbsolutePath.make(externalDirectory))) ?? externalDirectory, "*"),
-          ),
-        },
+        canonical: resolved.canonical,
+        resource,
+        externalDirectory: external
+          ? {
+              action: "external_directory",
+              directory: externalDirectory,
+              resource: externalResource,
+              save: slash(
+                path.join((yield* Project.root(fs, AbsolutePath.make(externalDirectory))) ?? externalDirectory, "*"),
+              ),
+            }
+          : undefined,
       } satisfies Target
     })
 

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

@@ -116,120 +116,124 @@ export const Plugin = {
 
     yield* ctx.tool
       .transform((draft) =>
-        draft.add({
-          name,
-          options: { codemode: false, permission: "edit" },
-          description:
-            "Edit the contents of a file by finding and replacing exact text. When editing text from Read output, preserve the exact indentation (tabs or spaces) and omit the line-number prefix, such as `1: `. Never include the prefix in oldString or newString. The edit fails if oldString is not found. By default, oldString must identify a UNIQUE location. Multiple matches FAIL unless replaceAll is true. Add more surrounding context to disambiguate, or set replaceAll to true to replace every occurrence. Use replaceAll when the change should apply to every occurrence, such as renaming a variable.",
-          input: Input,
-          output: Output,
-          execute: (input, context) => {
-            return Effect.gen(function* () {
-              const permissionSource = {
-                type: "tool" as const,
-                messageID: context.messageID,
-                id: context.id,
-              }
-              if (input.oldString === input.newString) {
-                return yield* new ToolFailure({
-                  message: "No changes to apply: oldString and newString are identical.",
-                })
-              }
-              if (input.oldString === "") {
-                return yield* new ToolFailure({
-                  message: "oldString must not be empty. Use write to create or overwrite a file.",
-                })
-              }
+        draft.add(
+          ({
+              name,
+              options: { codemode: false, permission: "edit" },
+              description:
+                "Edit the contents of a file by finding and replacing exact text. When editing text from Read output, preserve the exact indentation (tabs or spaces) and omit the line-number prefix, such as `1: `. Never include the prefix in oldString or newString. The edit fails if oldString is not found. By default, oldString must identify a UNIQUE location. Multiple matches FAIL unless replaceAll is true. Add more surrounding context to disambiguate, or set replaceAll to true to replace every occurrence. Use replaceAll when the change should apply to every occurrence, such as renaming a variable.",
+              input: Input,
+              output: Output,
+              execute: (input, context) => {
+                return Effect.gen(function* () {
+                  const permissionSource = {
+                    type: "tool" as const,
+                    messageID: context.messageID,
+                    id: context.id,
+                  }
+                  if (input.oldString === input.newString) {
+                    return yield* new ToolFailure({
+                      message: "No changes to apply: oldString and newString are identical.",
+                    })
+                  }
+                  if (input.oldString === "") {
+                    return yield* new ToolFailure({
+                      message: "oldString must not be empty. Use write to create or overwrite a file.",
+                    })
+                  }
 
-              const target = yield* mutation.resolve({ path: input.path, kind: "file" })
-              const external = target.externalDirectory
-              if (external) {
-                yield* permission.assert({
-                  ...LocationMutation.externalDirectoryPermission(external),
-                  sessionID: context.sessionID,
-                  agent: context.agent,
-                  source: permissionSource,
-                })
-              }
+                  const target = yield* mutation.resolve({ path: input.path, kind: "file" })
+                  const external = target.externalDirectory
+                  if (external) {
+                    yield* permission.assert({
+                      ...LocationMutation.externalDirectoryPermission(external),
+                      sessionID: context.sessionID,
+                      agent: context.agent,
+                      source: permissionSource,
+                    })
+                  }
 
-              const info = yield* fs
-                .stat(target.absolute)
-                .pipe(
-                  Effect.catchReason("PlatformError", "NotFound", () =>
-                    Effect.fail(new ToolFailure({ message: `File not found: ${input.path}` })),
+                  const info = yield* fs.stat(target.canonical).pipe(
+                    Effect.catchReason("PlatformError", "NotFound", () =>
+                      Effect.fail(new ToolFailure({ message: `File not found: ${input.path}` })),
+                    ),
+                  )
+                  if (info.type === "Directory") {
+                    return yield* new ToolFailure({ message: `Path is a directory, not a file: ${input.path}` })
+                  }
+                  const original = yield* Bom.readFile(fs, target.canonical)
+                  const source = original.text
+                  const ending = source.includes(crlf) ? crlf : "\n"
+                  const oldString = input.oldString.replaceAll(crlf, "\n").replaceAll("\n", ending)
+                  const newString = input.newString.replaceAll(crlf, "\n").replaceAll("\n", ending)
+                  const exact = findOccurrences(source, oldString)
+                  // These one-to-one mappings preserve offsets into the original source.
+                  const unicode =
+                    exact.length > 0 ? [] : findOccurrences(normalizeForMatch(source), normalizeForMatch(oldString))
+                  const trailing =
+                    exact.length > 0 || unicode.length > 0
+                      ? []
+                      : findLineOccurrences(source, oldString)
+                  const matches = exact.length > 0 ? exact : unicode.length > 0 ? unicode : trailing
+                  const replacements = matches.length
+                  const replaced = (input.replaceAll === true ? matches : matches.slice(0, 1))
+                    .toReversed()
+                    .reduce(
+                      (content, match) =>
+                        `${content.slice(0, match.start)}${newString}${content.slice(match.end)}`,
+                      source,
+                    )
+                  const preview =
+                    replacements > 0 && (replacements === 1 || input.replaceAll === true)
+                      ? fileDiff(target.resource, source, replaced)
+                      : undefined
+                  yield* permission.assert({
+                    action: "edit",
+                    resources: [target.resource],
+                    save: ["*"],
+                    metadata: preview ? { files: [preview] } : undefined,
+                    sessionID: context.sessionID,
+                    agent: context.agent,
+                    source: permissionSource,
+                  })
+                  if (replacements === 0) {
+                    return yield* new ToolFailure({
+                      message: `Could not find oldString in ${input.path}. It must match exactly, including whitespace and indentation.`,
+                    })
+                  }
+                  if (replacements > 1 && input.replaceAll !== true) {
+                    return yield* new ToolFailure({
+                      message: `Found ${replacements} matches for oldString, but expected exactly one. Add more surrounding context to make oldString unique, or set replaceAll to true to replace every occurrence.`,
+                    })
+                  }
+                  const replacementBom = replaced.startsWith("\uFEFF")
+                  const result = yield* files.write({
+                    target,
+                    content: Bom.join(replaced, original.bom || replacementBom),
+                  })
+                  const bom = original.bom || replacementBom
+                  const formatted = (yield* formatter.file(target.canonical))
+                    ? yield* Bom.syncFile(fs, target.canonical, bom)
+                    : (yield* Bom.readFile(fs, target.canonical)).text
+                  return {
+                    files: [fileDiff(result.resource, source, formatted)],
+                    replacements,
+                  } satisfies Output
+                }).pipe(
+                  Effect.map((output) => ({
+                    output,
+                    content: `Edited ${output.files[0]?.file} (${output.replacements} replacement${output.replacements === 1 ? "" : "s"})`,
+                    metadata: { files: output.files },
+                  })),
+                  Effect.mapError((error) =>
+                    error instanceof ToolFailure
+                      ? error
+                      : new ToolFailure({ message: `Unable to edit ${input.path}`, error }),
                   ),
                 )
-              if (info.type === "Directory") {
-                return yield* new ToolFailure({ message: `Path is a directory, not a file: ${input.path}` })
-              }
-              const original = yield* Bom.readFile(fs, target.absolute)
-              const source = original.text
-              const ending = source.includes(crlf) ? crlf : "\n"
-              const oldString = input.oldString.replaceAll(crlf, "\n").replaceAll("\n", ending)
-              const newString = input.newString.replaceAll(crlf, "\n").replaceAll("\n", ending)
-              const exact = findOccurrences(source, oldString)
-              // These one-to-one mappings preserve offsets into the original source.
-              const unicode =
-                exact.length > 0 ? [] : findOccurrences(normalizeForMatch(source), normalizeForMatch(oldString))
-              const trailing = exact.length > 0 || unicode.length > 0 ? [] : findLineOccurrences(source, oldString)
-              const matches = exact.length > 0 ? exact : unicode.length > 0 ? unicode : trailing
-              const replacements = matches.length
-              const replaced = (input.replaceAll === true ? matches : matches.slice(0, 1))
-                .toReversed()
-                .reduce(
-                  (content, match) => `${content.slice(0, match.start)}${newString}${content.slice(match.end)}`,
-                  source,
-                )
-              const preview =
-                replacements > 0 && (replacements === 1 || input.replaceAll === true)
-                  ? fileDiff(target.resource, source, replaced)
-                  : undefined
-              yield* permission.assert({
-                action: "edit",
-                resources: [target.resource],
-                save: ["*"],
-                metadata: preview ? { files: [preview] } : undefined,
-                sessionID: context.sessionID,
-                agent: context.agent,
-                source: permissionSource,
-              })
-              if (replacements === 0) {
-                return yield* new ToolFailure({
-                  message: `Could not find oldString in ${input.path}. It must match exactly, including whitespace and indentation.`,
-                })
-              }
-              if (replacements > 1 && input.replaceAll !== true) {
-                return yield* new ToolFailure({
-                  message: `Found ${replacements} matches for oldString, but expected exactly one. Add more surrounding context to make oldString unique, or set replaceAll to true to replace every occurrence.`,
-                })
-              }
-              const replacementBom = replaced.startsWith("\uFEFF")
-              const result = yield* files.write({
-                target,
-                content: Bom.join(replaced, original.bom || replacementBom),
-              })
-              const bom = original.bom || replacementBom
-              const formatted = (yield* formatter.file(target.absolute))
-                ? yield* Bom.syncFile(fs, target.absolute, bom)
-                : (yield* Bom.readFile(fs, target.absolute)).text
-              return {
-                files: [fileDiff(result.resource, source, formatted)],
-                replacements,
-              } satisfies Output
-            }).pipe(
-              Effect.map((output) => ({
-                output,
-                content: `Edited ${output.files[0]?.file} (${output.replacements} replacement${output.replacements === 1 ? "" : "s"})`,
-                metadata: { files: output.files },
-              })),
-              Effect.mapError((error) =>
-                error instanceof ToolFailure
-                  ? error
-                  : new ToolFailure({ message: `Unable to edit ${input.path}`, error }),
-              ),
-            )
-          },
-        }),
+              },
+            }),
+        ),
       )
       .pipe(Effect.orDie)
   }),

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

@@ -50,93 +50,96 @@ export const Plugin = {
 
     yield* ctx.tool
       .transform((draft) =>
-        draft.add({
-          name,
-          options: { codemode: false },
-          description: 'Search file paths using a glob pattern (examples: "**/*.ts", "src/**/*.tsx").',
-          input: Input,
-          output: Output,
-          execute: (input, context) =>
-            Effect.gen(function* () {
-              const searchPath = input.path === "undefined" || input.path === "null" ? undefined : input.path
-              const source = { type: "tool" as const, messageID: context.messageID, id: context.id }
-              const target = yield* mutation.resolve({ path: searchPath ?? ".", kind: "directory" })
-              const external = target.externalDirectory
-              if (external)
+        draft.add(
+          ({
+            name,
+            options: { codemode: false },
+            description:
+              'Search file paths using a glob pattern (examples: "**/*.ts", "src/**/*.tsx").',
+            input: Input,
+            output: Output,
+            execute: (input, context) =>
+              Effect.gen(function* () {
+                const searchPath = input.path === "undefined" || input.path === "null" ? undefined : input.path
+                const source = { type: "tool" as const, messageID: context.messageID, id: context.id }
+                const target = yield* mutation.resolve({ path: searchPath ?? ".", kind: "directory" })
+                const external = target.externalDirectory
+                if (external)
+                  yield* permission.assert({
+                    ...LocationMutation.externalDirectoryPermission(external),
+                    sessionID: context.sessionID,
+                    agent: context.agent,
+                    source,
+                  })
                 yield* permission.assert({
-                  ...LocationMutation.externalDirectoryPermission(external),
+                  action: name,
+                  resources: [input.pattern],
+                  save: ["*"],
+                  metadata: {
+                    root: searchPath ?? ".",
+                    path: searchPath,
+                    limit: input.limit,
+                  },
                   sessionID: context.sessionID,
                   agent: context.agent,
                   source,
                 })
-              yield* permission.assert({
-                action: name,
-                resources: [input.pattern],
-                save: ["*"],
-                metadata: {
-                  root: searchPath ?? ".",
-                  path: searchPath,
-                  limit: input.limit,
-                },
-                sessionID: context.sessionID,
-                agent: context.agent,
-                source,
-              })
-              const info = yield* fs
-                .stat(target.absolute)
-                .pipe(
-                  Effect.catchReason("PlatformError", "NotFound", () =>
-                    Effect.fail(new ToolFailure({ message: `Search path does not exist: ${searchPath ?? "."}` })),
-                  ),
-                )
-              if (info.type !== "Directory")
-                return yield* Effect.fail(
-                  new ToolFailure({ message: `Search path is not a directory: ${searchPath ?? "."}` }),
-                )
-              const root = path.resolve(location.directory, searchPath ?? ".")
-              const limit = input.limit ?? FileSystem.DEFAULT_SEARCH_LIMIT
-              const entries = yield* ripgrep
-                .glob({
-                  cwd: target.absolute,
-                  pattern: input.pattern,
-                  limit: limit + 1,
-                })
-                .pipe(
-                  Effect.timeoutOrElse({
-                    duration: FileSystem.DEFAULT_SEARCH_TIMEOUT_MS,
-                    orElse: () =>
-                      Effect.fail(
-                        new ToolFailure({
-                          message: `Search timed out after ${FileSystem.DEFAULT_SEARCH_TIMEOUT_MS / 1_000} seconds. Consider using a more specific path or pattern.`,
+                const info = yield* fs
+                  .stat(target.canonical)
+                  .pipe(
+                    Effect.catchReason("PlatformError", "NotFound", () =>
+                      Effect.fail(new ToolFailure({ message: `Search path does not exist: ${searchPath ?? "."}` })),
+                    ),
+                  )
+                if (info.type !== "Directory")
+                  return yield* Effect.fail(
+                    new ToolFailure({ message: `Search path is not a directory: ${searchPath ?? "."}` }),
+                  )
+                const root = path.resolve(location.directory, searchPath ?? ".")
+                const limit = input.limit ?? FileSystem.DEFAULT_SEARCH_LIMIT
+                const entries = yield* ripgrep
+                  .glob({
+                    cwd: target.canonical,
+                    pattern: input.pattern,
+                    limit: limit + 1,
+                  })
+                  .pipe(
+                    Effect.timeoutOrElse({
+                      duration: FileSystem.DEFAULT_SEARCH_TIMEOUT_MS,
+                      orElse: () =>
+                        Effect.fail(
+                          new ToolFailure({
+                            message: `Search timed out after ${FileSystem.DEFAULT_SEARCH_TIMEOUT_MS / 1_000} seconds. Consider using a more specific path or pattern.`,
+                          }),
+                        ),
+                    }),
+                    Effect.map((result) =>
+                      result.map((entry) =>
+                        FileSystem.Entry.make({
+                          ...entry,
+                          path: RelativePath.make(path.relative(location.directory, path.resolve(root, entry.path))),
                         }),
                       ),
-                  }),
-                  Effect.map((result) =>
-                    result.map((entry) =>
-                      FileSystem.Entry.make({
-                        ...entry,
-                        path: RelativePath.make(path.relative(location.directory, path.resolve(root, entry.path))),
-                      }),
                     ),
+                  )
+                return { entries: entries.slice(0, limit), truncated: entries.length > limit }
+              }).pipe(
+                Effect.map((result) => ({
+                  output: result.entries,
+                  content: toModelContent(
+                    result.entries.map((entry) => ({ ...entry, path: path.resolve(location.directory, entry.path) })),
+                    result.truncated,
                   ),
-                )
-              return { entries: entries.slice(0, limit), truncated: entries.length > limit }
-            }).pipe(
-              Effect.map((result) => ({
-                output: result.entries,
-                content: toModelContent(
-                  result.entries.map((entry) => ({ ...entry, path: path.resolve(location.directory, entry.path) })),
-                  result.truncated,
+                  metadata: { count: result.entries.length, truncated: result.truncated },
+                })),
+                Effect.mapError((error) =>
+                  error instanceof ToolFailure
+                    ? error
+                    : new ToolFailure({ message: `Unable to find files matching ${input.pattern}`, error }),
                 ),
-                metadata: { count: result.entries.length, truncated: result.truncated },
-              })),
-              Effect.mapError((error) =>
-                error instanceof ToolFailure
-                  ? error
-                  : new ToolFailure({ message: `Unable to find files matching ${input.pattern}`, error }),
               ),
-            ),
-        }),
+          }),
+        ),
       )
       .pipe(Effect.orDie)
   }),

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

@@ -58,7 +58,7 @@ type Prepared =
     })
 
 interface Target {
-  readonly absolute: string
+  readonly canonical: string
   readonly resource: string
   readonly externalDirectory?: {
     readonly directory: string
@@ -76,256 +76,267 @@ export const Plugin = {
 
     yield* ctx.tool
       .transform((draft) =>
-        draft.add({
-          name,
-          options: { codemode: false, permission: "edit" },
-          description: DESCRIPTION,
-          input: Input,
-          output: Output,
-          execute: (input, context) => {
-            const applied: Array<typeof Applied.Type> = []
-            const fail = (operation: string, error: unknown) => {
-              const completed = applied.map((item) => item.resource).join(", ")
-              return new ToolFailure({
-                message: `${operation}: ${errorMessage(error)}${completed ? `. Completed before failure: ${completed}` : ""}`,
-              })
-            }
-            return Effect.gen(function* () {
-              const source = {
-                type: "tool" as const,
-                messageID: context.messageID,
-                id: context.id,
-              }
-              if (!input.patchText) return yield* new ToolFailure({ message: "patchText is required" })
-              const hunks = yield* Effect.fromResult(Patch.parse(input.patchText)).pipe(
-                Effect.mapError((error) => new ToolFailure({ message: `patch verification failed: ${error.message}` })),
-              )
-              if (hunks.length === 0) {
-                return yield* new ToolFailure({ message: "patch rejected: empty patch" })
-              }
-              const prepared: Prepared[] = []
-              const targets: Target[] = []
-              const updates = new Map<string, string>()
-              for (const hunk of hunks) {
-                yield* Effect.gen(function* () {
-                  const target = resolveTarget(location, hunk.path)
-                  targets.push(target)
-                  if (target.externalDirectory) {
-                    yield* permission.assert({
-                      action: "external_directory",
-                      resources: [target.externalDirectory.resource],
-                      save: [target.externalDirectory.resource],
-                      metadata: {
-                        filepath: target.absolute,
-                        parentDir: target.externalDirectory.directory,
-                      },
-                      sessionID: context.sessionID,
-                      agent: context.agent,
-                      source,
-                    })
+        draft.add(
+          ({
+              name,
+              options: { codemode: false, permission: "edit" },
+              description: DESCRIPTION,
+              input: Input,
+              output: Output,
+              execute: (input, context) => {
+                const applied: Array<typeof Applied.Type> = []
+                const fail = (operation: string, error: unknown) => {
+                  const completed = applied.map((item) => item.resource).join(", ")
+                  return new ToolFailure({
+                    message: `${operation}: ${errorMessage(error)}${completed ? `. Completed before failure: ${completed}` : ""}`,
+                  })
+                }
+                return Effect.gen(function* () {
+                  const source = {
+                    type: "tool" as const,
+                    messageID: context.messageID,
+                    id: context.id,
                   }
-                  if (hunk.type === "add") {
-                    prepared.push({
-                      ...hunk,
-                      target,
-                      before: "",
-                      after: Bom.split(
-                        hunk.contents.endsWith("\n") || hunk.contents === "" ? hunk.contents : `${hunk.contents}\n`,
-                      ).text,
-                    })
-                    return
+                  if (!input.patchText) return yield* new ToolFailure({ message: "patchText is required" })
+                  const hunks = yield* Effect.fromResult(Patch.parse(input.patchText)).pipe(
+                    Effect.mapError(
+                      (error) => new ToolFailure({ message: `patch verification failed: ${error.message}` }),
+                    ),
+                  )
+                  if (hunks.length === 0) {
+                    return yield* new ToolFailure({ message: "patch rejected: empty patch" })
                   }
-                  if (hunk.type === "delete") {
-                    const content = yield* Bom.readFile(fs, target.absolute).pipe(
-                      Effect.mapError(
-                        (error) =>
-                          new ToolFailure({
-                            message: `patch verification failed: Failed to delete ${target.resource}: ${errorMessage(error)}`,
-                          }),
-                      ),
-                    )
-                    prepared.push({ ...hunk, target, before: content.text, after: "" })
-                    return
-                  }
-                  const previous = updates.get(target.absolute)
-                  const original =
-                    previous ??
-                    (yield* Effect.gen(function* () {
-                      const stats = yield* fs.stat(target.absolute).pipe(
-                        Effect.mapError(
-                          (error) =>
-                            new ToolFailure({
-                              message: `patch verification failed: Failed to read file to update ${target.absolute}: ${errorMessage(error)}`,
-                            }),
-                        ),
-                      )
-                      if (stats.type === "Directory") {
-                        return yield* new ToolFailure({
-                          message: `patch verification failed: Failed to read file to update ${target.absolute}: path is a directory`,
+                  const prepared: Prepared[] = []
+                  const targets: Target[] = []
+                  const updates = new Map<string, string>()
+                  for (const hunk of hunks) {
+                    yield* Effect.gen(function* () {
+                      const target = resolveTarget(location, hunk.path)
+                      targets.push(target)
+                      if (target.externalDirectory) {
+                        yield* permission.assert({
+                          action: "external_directory",
+                          resources: [target.externalDirectory.resource],
+                          save: [target.externalDirectory.resource],
+                          metadata: {
+                            filepath: target.canonical,
+                            parentDir: target.externalDirectory.directory,
+                          },
+                          sessionID: context.sessionID,
+                          agent: context.agent,
+                          source,
                         })
                       }
-                      const content = yield* Bom.readFile(fs, target.absolute).pipe(
-                        Effect.mapError(
-                          (error) =>
-                            new ToolFailure({
-                              message: `patch verification failed: Failed to read file to update ${target.absolute}: ${errorMessage(error)}`,
-                            }),
-                        ),
-                      )
-                      return Bom.join(content.text, content.bom)
-                    }))
-                  const before = Bom.split(original).text
-                  const update = yield* Effect.try({
-                    try: () => Patch.derive(hunk.path, hunk.chunks, original),
-                    catch: (error) => new ToolFailure({ message: `patch verification failed: ${errorMessage(error)}` }),
-                  })
-                  const moveTarget = hunk.movePath ? resolveTarget(location, hunk.movePath) : undefined
-                  if (moveTarget) targets.push(moveTarget)
-                  if (moveTarget?.externalDirectory) {
-                    yield* permission.assert({
-                      action: "external_directory",
-                      resources: [moveTarget.externalDirectory.resource],
-                      save: [moveTarget.externalDirectory.resource],
-                      metadata: {
-                        filepath: moveTarget.absolute,
-                        parentDir: moveTarget.externalDirectory.directory,
-                      },
-                      sessionID: context.sessionID,
-                      agent: context.agent,
-                      source,
-                    })
+                      if (hunk.type === "add") {
+                        prepared.push({
+                          ...hunk,
+                          target,
+                          before: "",
+                          after: Bom.split(
+                            hunk.contents.endsWith("\n") || hunk.contents === ""
+                              ? hunk.contents
+                              : `${hunk.contents}\n`,
+                          ).text,
+                        })
+                        return
+                      }
+                      if (hunk.type === "delete") {
+                        const content = yield* Bom.readFile(fs, target.canonical).pipe(
+                          Effect.mapError(
+                            (error) =>
+                              new ToolFailure({
+                                message: `patch verification failed: Failed to delete ${target.resource}: ${errorMessage(error)}`,
+                              }),
+                          ),
+                        )
+                        prepared.push({ ...hunk, target, before: content.text, after: "" })
+                        return
+                      }
+                      const previous = updates.get(target.canonical)
+                      const original =
+                        previous ??
+                        (yield* Effect.gen(function* () {
+                          const stats = yield* fs.stat(target.canonical).pipe(
+                            Effect.mapError(
+                              (error) =>
+                                new ToolFailure({
+                                  message: `patch verification failed: Failed to read file to update ${target.canonical}: ${errorMessage(error)}`,
+                                }),
+                            ),
+                          )
+                          if (stats.type === "Directory") {
+                            return yield* new ToolFailure({
+                              message: `patch verification failed: Failed to read file to update ${target.canonical}: path is a directory`,
+                            })
+                          }
+                          const content = yield* Bom.readFile(fs, target.canonical).pipe(
+                            Effect.mapError(
+                              (error) =>
+                                new ToolFailure({
+                                  message: `patch verification failed: Failed to read file to update ${target.canonical}: ${errorMessage(error)}`,
+                                }),
+                            ),
+                          )
+                          return Bom.join(content.text, content.bom)
+                        }))
+                      const before = Bom.split(original).text
+                      const update = yield* Effect.try({
+                        try: () => Patch.derive(hunk.path, hunk.chunks, original),
+                        catch: (error) =>
+                          new ToolFailure({ message: `patch verification failed: ${errorMessage(error)}` }),
+                      })
+                      const moveTarget = hunk.movePath ? resolveTarget(location, hunk.movePath) : undefined
+                      if (moveTarget) targets.push(moveTarget)
+                      if (moveTarget?.externalDirectory) {
+                        yield* permission.assert({
+                          action: "external_directory",
+                          resources: [moveTarget.externalDirectory.resource],
+                          save: [moveTarget.externalDirectory.resource],
+                          metadata: {
+                            filepath: moveTarget.canonical,
+                            parentDir: moveTarget.externalDirectory.directory,
+                          },
+                          sessionID: context.sessionID,
+                          agent: context.agent,
+                          source,
+                        })
+                      }
+                      prepared.push({
+                        ...hunk,
+                        target,
+                        content: Patch.joinBom(update.content, update.bom),
+                        before,
+                        after: update.content,
+                        moveTarget,
+                      })
+                      if (!moveTarget) updates.set(target.canonical, Patch.joinBom(update.content, update.bom))
+                    }).pipe(
+                      Effect.mapError((error) =>
+                        error instanceof ToolFailure
+                          ? error
+                          : new ToolFailure({ message: `Unable to prepare patch at ${hunk.path}`, error }),
+                      ),
+                    )
                   }
-                  prepared.push({
-                    ...hunk,
-                    target,
-                    content: Patch.joinBom(update.content, update.bom),
-                    before,
-                    after: update.content,
-                    moveTarget,
+
+                  const patchFiles = prepared.map((change) => patchFile(change))
+                  yield* permission.assert({
+                    action: "edit",
+                    resources: [...new Set(targets.map((target) => target.resource))],
+                    save: ["*"],
+                    metadata: {
+                      filepath: targets.map((target) => target.resource).join(", "),
+                      diff: patchFiles.map((file) => `${file.patch}\n`).join(""),
+                      files: patchFiles,
+                    },
+                    sessionID: context.sessionID,
+                    agent: context.agent,
+                    source,
                   })
-                  if (!moveTarget) updates.set(target.absolute, Patch.joinBom(update.content, update.bom))
+
+                  yield* Effect.forEach(
+                    prepared,
+                    (change) =>
+                      Effect.gen(function* () {
+                        if (change.type === "add") {
+                          yield* fs
+                            .writeWithDirs(
+                              change.target.canonical,
+                              change.contents.endsWith("\n") || change.contents === ""
+                                ? change.contents
+                                : `${change.contents}\n`,
+                            )
+                            .pipe(
+                              Effect.mapError((error) => fail(`Failed to write ${change.target.resource}`, error)),
+                            )
+                          applied.push({
+                            type: change.type,
+                            resource: change.target.resource,
+                            target: change.target.canonical,
+                          })
+                          return
+                        }
+                        if (change.type === "delete") {
+                          yield* fs
+                            .remove(change.target.canonical)
+                            .pipe(
+                              Effect.mapError((error) => fail(`Failed to delete ${change.target.resource}`, error)),
+                            )
+                          applied.push({
+                            type: change.type,
+                            resource: change.target.resource,
+                            target: change.target.canonical,
+                          })
+                          return
+                        }
+                        if (change.moveTarget) {
+                          const moveTarget = change.moveTarget
+                          yield* fs
+                            .writeWithDirs(moveTarget.canonical, change.content)
+                            .pipe(Effect.mapError((error) => fail(`Failed to write ${moveTarget.resource}`, error)))
+                          yield* fs.remove(change.target.canonical).pipe(
+                            Effect.mapError((error) =>
+                              fail(`Wrote ${moveTarget.resource} but failed to remove ${change.target.resource}`, error),
+                            ),
+                          )
+                          applied.push({
+                            type: change.type,
+                            resource: change.moveTarget.resource,
+                            target: change.moveTarget.canonical,
+                          })
+                          return
+                        }
+                        yield* fs
+                          .writeWithDirs(change.target.canonical, change.content)
+                          .pipe(Effect.mapError((error) => fail(`Failed to write ${change.target.resource}`, error)))
+                        applied.push({
+                          type: change.type,
+                          resource: change.target.resource,
+                          target: change.target.canonical,
+                        })
+                      }),
+                    { discard: true },
+                  )
+                  const formatted = new Map<string, string>()
+                  yield* Effect.forEach(
+                    [...new Set(applied.filter((item) => item.type !== "delete").map((item) => item.target))],
+                    (target) =>
+                      Effect.gen(function* () {
+                        const current = yield* Bom.readFile(fs, target).pipe(
+                          Effect.mapError((error) => fail(`Failed to read ${target}`, error)),
+                        )
+                        formatted.set(
+                          target,
+                          (yield* formatter.file(target))
+                            ? yield* Bom.syncFile(fs, target, current.bom).pipe(
+                                Effect.mapError((error) => fail(`Failed to sync ${target}`, error)),
+                              )
+                            : current.text,
+                        )
+                      }),
+                    { discard: true },
+                  )
+                  const files = yield* Effect.forEach(prepared, (change) => {
+                    if (change.type === "delete") return Effect.succeed(patchFile(change))
+                    const target = change.type === "update" && change.moveTarget ? change.moveTarget : change.target
+                    return Effect.succeed(patchFile(change, formatted.get(target.canonical)))
+                  })
+                  return { applied, files }
                 }).pipe(
+                  Effect.map((output) => ({
+                    output,
+                    content: toModelOutput(output),
+                    metadata: { files: output.files },
+                  })),
                   Effect.mapError((error) =>
                     error instanceof ToolFailure
                       ? error
-                      : new ToolFailure({ message: `Unable to prepare patch at ${hunk.path}`, error }),
+                      : new ToolFailure({ message: "Unable to apply patch", error }),
                   ),
                 )
-              }
-
-              const patchFiles = prepared.map((change) => patchFile(change))
-              yield* permission.assert({
-                action: "edit",
-                resources: [...new Set(targets.map((target) => target.resource))],
-                save: ["*"],
-                metadata: {
-                  filepath: targets.map((target) => target.resource).join(", "),
-                  diff: patchFiles.map((file) => `${file.patch}\n`).join(""),
-                  files: patchFiles,
-                },
-                sessionID: context.sessionID,
-                agent: context.agent,
-                source,
-              })
-
-              yield* Effect.forEach(
-                prepared,
-                (change) =>
-                  Effect.gen(function* () {
-                    if (change.type === "add") {
-                      yield* fs
-                        .writeWithDirs(
-                          change.target.absolute,
-                          change.contents.endsWith("\n") || change.contents === ""
-                            ? change.contents
-                            : `${change.contents}\n`,
-                        )
-                        .pipe(Effect.mapError((error) => fail(`Failed to write ${change.target.resource}`, error)))
-                      applied.push({
-                        type: change.type,
-                        resource: change.target.resource,
-                        target: change.target.absolute,
-                      })
-                      return
-                    }
-                    if (change.type === "delete") {
-                      yield* fs
-                        .remove(change.target.absolute)
-                        .pipe(Effect.mapError((error) => fail(`Failed to delete ${change.target.resource}`, error)))
-                      applied.push({
-                        type: change.type,
-                        resource: change.target.resource,
-                        target: change.target.absolute,
-                      })
-                      return
-                    }
-                    if (change.moveTarget) {
-                      const moveTarget = change.moveTarget
-                      yield* fs
-                        .writeWithDirs(moveTarget.absolute, change.content)
-                        .pipe(Effect.mapError((error) => fail(`Failed to write ${moveTarget.resource}`, error)))
-                      yield* fs
-                        .remove(change.target.absolute)
-                        .pipe(
-                          Effect.mapError((error) =>
-                            fail(`Wrote ${moveTarget.resource} but failed to remove ${change.target.resource}`, error),
-                          ),
-                        )
-                      applied.push({
-                        type: change.type,
-                        resource: change.moveTarget.resource,
-                        target: change.moveTarget.absolute,
-                      })
-                      return
-                    }
-                    yield* fs
-                      .writeWithDirs(change.target.absolute, change.content)
-                      .pipe(Effect.mapError((error) => fail(`Failed to write ${change.target.resource}`, error)))
-                    applied.push({
-                      type: change.type,
-                      resource: change.target.resource,
-                      target: change.target.absolute,
-                    })
-                  }),
-                { discard: true },
-              )
-              const formatted = new Map<string, string>()
-              yield* Effect.forEach(
-                [...new Set(applied.filter((item) => item.type !== "delete").map((item) => item.target))],
-                (target) =>
-                  Effect.gen(function* () {
-                    const current = yield* Bom.readFile(fs, target).pipe(
-                      Effect.mapError((error) => fail(`Failed to read ${target}`, error)),
-                    )
-                    formatted.set(
-                      target,
-                      (yield* formatter.file(target))
-                        ? yield* Bom.syncFile(fs, target, current.bom).pipe(
-                            Effect.mapError((error) => fail(`Failed to sync ${target}`, error)),
-                          )
-                        : current.text,
-                    )
-                  }),
-                { discard: true },
-              )
-              const files = yield* Effect.forEach(prepared, (change) => {
-                if (change.type === "delete") return Effect.succeed(patchFile(change))
-                const target = change.type === "update" && change.moveTarget ? change.moveTarget : change.target
-                return Effect.succeed(patchFile(change, formatted.get(target.absolute)))
-              })
-              return { applied, files }
-            }).pipe(
-              Effect.map((output) => ({
-                output,
-                content: toModelOutput(output),
-                metadata: { files: output.files },
-              })),
-              Effect.mapError((error) =>
-                error instanceof ToolFailure ? error : new ToolFailure({ message: "Unable to apply patch", error }),
-              ),
-            )
-          },
-        }),
+              },
+            }),
+        ),
       )
       .pipe(Effect.orDie)
 
@@ -354,7 +365,9 @@ function errorMessage(error: unknown) {
 
 function patchFile(change: Prepared, after = change.after): typeof FileDiff.Info.Type {
   const target = (change.type === "update" ? change.moveTarget : undefined)?.resource ?? change.target.resource
-  const patch = trimDiff(createTwoFilesPatch(change.target.absolute, change.target.absolute, change.before, after))
+  const patch = trimDiff(
+    createTwoFilesPatch(change.target.canonical, change.target.canonical, change.before, after),
+  )
   const counts =
     change.type === "delete"
       ? { additions: 0, deletions: change.before.split("\n").length }
@@ -403,22 +416,22 @@ function trimDiff(diff: string) {
 }
 
 function resolveTarget(location: Location.Interface, value: string): Target {
-  const absolute =
+  const canonical =
     process.platform === "win32"
       ? FSUtil.normalizePath(path.resolve(location.directory, value))
       : path.resolve(location.directory, value)
   const projectRoot = path.parse(location.project.directory).root
   const external =
-    !FSUtil.contains(location.directory, absolute) &&
-    (location.project.directory === projectRoot || !FSUtil.contains(location.project.directory, absolute))
-  const directory = path.dirname(absolute)
+    !FSUtil.contains(location.directory, canonical) &&
+    (location.project.directory === projectRoot || !FSUtil.contains(location.project.directory, canonical))
+  const directory = path.dirname(canonical)
   const resource =
     process.platform === "win32"
       ? FSUtil.normalizePathPattern(path.join(directory, "*"))
       : path.join(directory, "*").replaceAll("\\", "/")
   return {
-    absolute,
-    resource: path.relative(location.project.directory, absolute).replaceAll("\\", "/") || ".",
+    canonical,
+    resource: path.relative(location.project.directory, canonical).replaceAll("\\", "/") || ".",
     externalDirectory: external ? { directory, resource } : undefined,
   }
 }

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

@@ -25,7 +25,11 @@ const LocationInput = Schema.Struct({
   }),
 })
 export const Input = LocationInput
-const Output = Schema.Union([ReadToolFileSystem.FileContent, ReadToolFileSystem.TextPage, ReadToolFileSystem.ListPage])
+const Output = Schema.Union([
+  ReadToolFileSystem.FileContent,
+  ReadToolFileSystem.TextPage,
+  ReadToolFileSystem.ListPage,
+])
 
 export const Plugin = {
   id: "opencode.tool.read",
@@ -39,102 +43,105 @@ export const Plugin = {
 
     yield* ctx.tool
       .transform((draft) =>
-        draft.add({
-          name,
-          options: { codemode: false },
-          description:
-            "Read the contents of a file or directory. Supports text files, images, and PDFs. Images and PDFs are presented directly to the model. Each text line is prefixed by its 1-based line number as <line>: <content>. The prefix is for reference and is not part of the file content. Directory entries are returned one per line. Use offset and limit to read large files or directories in sections. Prefer one larger read over many small slices, and use grep to find specific content in large files.",
-          input: Input,
-          output: Output,
-          execute: (input, context) => {
-            return Effect.gen(function* () {
-              const source = {
-                type: "tool" as const,
-                messageID: context.messageID,
-                id: context.id,
-              }
-              const target = yield* mutation.resolve({ path: input.path })
-              const external = target.externalDirectory
-              if (external)
+        draft.add(
+          ({
+            name,
+            options: { codemode: false },
+            description:
+              "Read the contents of a file or directory. Supports text files, images, and PDFs. Images and PDFs are presented directly to the model. Each text line is prefixed by its 1-based line number as <line>: <content>. The prefix is for reference and is not part of the file content. Directory entries are returned one per line. Use offset and limit to read large files or directories in sections. Prefer one larger read over many small slices, and use grep to find specific content in large files.",
+            input: Input,
+            output: Output,
+            execute: (input, context) => {
+              return Effect.gen(function* () {
+                const source = {
+                  type: "tool" as const,
+                  messageID: context.messageID,
+                  id: context.id,
+                }
+                const target = yield* mutation.resolve({ path: input.path, kind: "directory" })
+                const external = target.externalDirectory
+                if (external)
+                  yield* permission.assert({
+                    ...LocationMutation.externalDirectoryPermission(external),
+                    sessionID: context.sessionID,
+                    agent: context.agent,
+                    source,
+                  })
+                const resource = target.resource
+                const absolute = AbsolutePath.make(target.canonical)
                 yield* permission.assert({
-                  ...LocationMutation.externalDirectoryPermission(external),
+                  action: name,
+                  resources: [resource],
+                  save: ["*"],
                   sessionID: context.sessionID,
                   agent: context.agent,
                   source,
                 })
-              const resource = target.resource
-              const absolute = AbsolutePath.make(target.absolute)
-              yield* permission.assert({
-                action: name,
-                resources: [resource],
-                save: ["*"],
-                sessionID: context.sessionID,
-                agent: context.agent,
-                source,
-              })
-              const type = yield* reader
-                .inspect(absolute)
-                .pipe(Effect.catchReason("PlatformError", "NotFound", () => missing(input.path, target.absolute)))
-              const content =
-                type === "directory"
-                  ? yield* reader.list(absolute, { offset: input.offset, limit: input.limit })
-                  : yield* reader.read(absolute, resource, {
-                      offset: input.offset,
-                      limit: input.limit,
-                    })
-              // After a successful read, discover nearby AGENTS.md walking up to the Location
-              // root exclusive and inject them as durable synthetic instructions. For a
-              // directory listing the walk starts at the directory itself (so its own AGENTS.md
-              // is discovered); for a file it starts at the file's dirname. External reads are
-              // skipped, and discovery failures never fail the read.
-              yield* Effect.gen(function* () {
-                if (target.externalDirectory !== undefined) return
-                const resolved = yield* fs.resolve(target.absolute)
-                const root = yield* fs.resolve(location.directory)
-                // up() searches its stop directory, so the Location-root AGENTS.md (already
-                // supplied by core initial instructions) is dropped by the dirname filter.
-                const discovered = yield* fs.up({
-                  targets: [FILENAME],
-                  start: type === "directory" ? resolved : dirname(resolved),
-                  stop: root,
-                })
-                const candidates = (yield* Effect.forEach(discovered, fs.resolve)).filter(
-                  (file) => dirname(file) !== root,
+                const type = yield* reader.inspect(absolute).pipe(
+                  Effect.catchReason("PlatformError", "NotFound", () => missing(input.path, target.canonical)),
                 )
-                if (candidates.length === 0) return
-                yield* sessionInstructions.load({ sessionID: context.sessionID, paths: candidates })
+                const content =
+                  type === "directory"
+                    ? yield* reader.list(absolute, { offset: input.offset, limit: input.limit })
+                    : yield* reader.read(absolute, resource, {
+                        offset: input.offset,
+                        limit: input.limit,
+                      })
+                // After a successful read, discover nearby AGENTS.md walking up to the Location
+                // root exclusive and inject them as durable synthetic instructions. For a
+                // directory listing the walk starts at the directory itself (so its own AGENTS.md
+                // is discovered); for a file it starts at the file's dirname. External reads are
+                // skipped, and discovery failures never fail the read.
+                yield* Effect.gen(function* () {
+                  if (target.externalDirectory !== undefined) return
+                  const resolved = yield* fs.resolve(target.canonical)
+                  const root = yield* fs.resolve(location.directory)
+                  // up() searches its stop directory, so the Location-root AGENTS.md (already
+                  // supplied by core initial instructions) is dropped by the dirname filter.
+                  const discovered = yield* fs.up({
+                    targets: [FILENAME],
+                    start: type === "directory" ? resolved : dirname(resolved),
+                    stop: root,
+                  })
+                  const candidates = (yield* Effect.forEach(discovered, fs.resolve)).filter(
+                    (file) => dirname(file) !== root,
+                  )
+                  if (candidates.length === 0) return
+                  yield* sessionInstructions.load({ sessionID: context.sessionID, paths: candidates })
+                }).pipe(
+                  Effect.catch(() => Effect.void),
+                  Effect.catchDefect(() => Effect.void),
+                )
+                if (content.type === "file" && content.encoding === "base64" && !SUPPORTED_MEDIA_MIMES.has(content.mime))
+                  return yield* Effect.fail(new ReadToolFileSystem.BinaryFileError({ resource }))
+                return content
               }).pipe(
-                Effect.catch(() => Effect.void),
-                Effect.catchDefect(() => Effect.void),
+                Effect.map((output) => ({
+                  output,
+                  content: toModelContent(input.path, input.offset, output),
+                })),
+                Effect.mapError((error) => {
+                  if (error instanceof ToolFailure) return error
+                  const message =
+                    error instanceof ReadToolFileSystem.BinaryFileError ||
+                    error instanceof ReadToolFileSystem.MediaIngestLimitError ||
+                    error instanceof ReadToolFileSystem.MalformedUtf8Error ||
+                    error instanceof ReadToolFileSystem.OffsetOutOfRangeError ||
+                    error instanceof ReadToolFileSystem.PathKindError
+                      ? error.message
+                      : `Unable to read ${input.path}`
+                  return new ToolFailure({ message, error })
+                }),
               )
-              if (content.type === "file" && content.encoding === "base64" && !SUPPORTED_MEDIA_MIMES.has(content.mime))
-                return yield* Effect.fail(new ReadToolFileSystem.BinaryFileError({ resource }))
-              return content
-            }).pipe(
-              Effect.map((output) => ({
-                output,
-                content: toModelContent(input.path, input.offset, output),
-              })),
-              Effect.mapError((error) => {
-                if (error instanceof ToolFailure) return error
-                const message =
-                  error instanceof ReadToolFileSystem.BinaryFileError ||
-                  error instanceof ReadToolFileSystem.MediaIngestLimitError ||
-                  error instanceof ReadToolFileSystem.OffsetOutOfRangeError ||
-                  error instanceof ReadToolFileSystem.PathKindError
-                    ? error.message
-                    : `Unable to read ${input.path}`
-                return new ToolFailure({ message, error })
-              }),
-            )
-          },
-        }),
+            },
+          }),
+        ),
       )
       .pipe(Effect.orDie)
 
-    const missing = Effect.fn("ReadTool.missing")(function* (input: string, absolute: string) {
+    const missing = Effect.fn("ReadTool.missing")(function* (input: string, canonical: string) {
       const base = basename(input).toLowerCase()
-      const suggestions = yield* fs.readDirectory(dirname(absolute)).pipe(
+      const suggestions = yield* fs.readDirectory(dirname(canonical)).pipe(
         Effect.map((entries) =>
           entries
             .filter((entry) => {

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

@@ -122,176 +122,174 @@ export const Plugin = {
 
     yield* ctx.tool
       .transform((draft) =>
-        draft.add({
-          name,
-          options: { codemode: false },
-          description: description(),
-          input: Input,
-          output: Output,
-          execute: (input, context) =>
-            Effect.gen(function* () {
-              const source = {
-                type: "tool" as const,
-                messageID: context.messageID,
-                id: context.id,
-              }
-              const timeout = input.background === true ? (input.timeout ?? 0) : (input.timeout ?? DEFAULT_TIMEOUT_MS)
-              let finalTimeout = timeout
-              const info = yield* shell.create(
-                {
-                  command: input.command,
-                  cwd: input.workdir,
-                  timeout,
-                  metadata: { sessionID: context.sessionID },
-                },
-                (invocation) =>
-                  Effect.gen(function* () {
-                    const target = yield* mutation.resolve({ path: invocation.cwd, kind: "directory" })
-                    const parsed = yield* ShellParse.scan(invocation.command, invocation.shell, target.absolute)
-                    const directories = yield* Effect.forEach(parsed.directories, (directory) =>
-                      mutation.resolve({ path: path.resolve(target.absolute, directory), kind: "directory" }),
-                    )
-                    invocation.cwd = target.absolute
-                    finalTimeout = invocation.timeout
-                    const external = [target, ...directories]
-                      .map((item) => item.externalDirectory)
-                      .filter((item) => item !== undefined)
-                      .filter(
-                        (item, index, items) => items.findIndex((other) => other.resource === item.resource) === index,
+        draft.add(
+          ({
+            name,
+            options: { codemode: false },
+            description: description(),
+            input: Input,
+            output: Output,
+            execute: (input, context) =>
+              Effect.gen(function* () {
+                const source = {
+                  type: "tool" as const,
+                  messageID: context.messageID,
+                  id: context.id,
+                }
+                const timeout = input.background === true ? (input.timeout ?? 0) : (input.timeout ?? DEFAULT_TIMEOUT_MS)
+                let finalTimeout = timeout
+                const info = yield* shell.create(
+                  {
+                    command: input.command,
+                    cwd: input.workdir,
+                    timeout,
+                    metadata: { sessionID: context.sessionID },
+                  },
+                  (invocation) =>
+                    Effect.gen(function* () {
+                      const target = yield* mutation.resolve({ path: invocation.cwd, kind: "directory" })
+                      const parsed = yield* ShellParse.scan(invocation.command, invocation.shell, target.canonical)
+                      const directories = yield* Effect.forEach(parsed.directories, (directory) =>
+                        mutation.resolve({ path: path.resolve(target.canonical, directory), kind: "directory" }),
                       )
-                    if (external.length > 0)
-                      yield* permission.assert({
-                        action: "external_directory",
-                        resources: external.map((item) => item.resource),
-                        save: external.map((item) => item.save),
-                        sessionID: context.sessionID,
-                        agent: context.agent,
-                        source,
-                      })
-                    if (parsed.commands.length > 0)
-                      yield* permission.assert({
-                        action: name,
-                        resources: parsed.commands.map((command) => command.resource),
-                        save: parsed.commands.map((command) => command.save),
-                        sessionID: context.sessionID,
-                        agent: context.agent,
-                        source,
-                      })
-                    const workdir = yield* fsUtil
-                      .stat(target.absolute)
-                      .pipe(
+                      invocation.cwd = target.canonical
+                      finalTimeout = invocation.timeout
+                      const external = [target, ...directories]
+                        .map((item) => item.externalDirectory)
+                        .filter((item) => item !== undefined)
+                        .filter((item, index, items) => items.findIndex((other) => other.resource === item.resource) === index)
+                      if (external.length > 0)
+                        yield* permission.assert({
+                          action: "external_directory",
+                          resources: external.map((item) => item.resource),
+                          save: external.map((item) => item.save),
+                          sessionID: context.sessionID,
+                          agent: context.agent,
+                          source,
+                        })
+                      if (parsed.commands.length > 0)
+                        yield* permission.assert({
+                          action: name,
+                          resources: parsed.commands.map((command) => command.resource),
+                          save: parsed.commands.map((command) => command.save),
+                          sessionID: context.sessionID,
+                          agent: context.agent,
+                          source,
+                        })
+                      const workdir = yield* fsUtil.stat(target.canonical).pipe(
                         Effect.catchReason("PlatformError", "NotFound", () =>
-                          Effect.fail(new Error(`Working directory does not exist: ${target.absolute}`)),
+                          Effect.fail(new Error(`Working directory does not exist: ${target.canonical}`)),
                         ),
                       )
-                    if (workdir.type !== "Directory")
-                      return yield* Effect.fail(new Error(`Working directory is not a directory: ${target.absolute}`))
-                  }),
-              )
-              yield* context.progress({ shellID: info.id })
+                      if (workdir.type !== "Directory")
+                        return yield* Effect.fail(new Error(`Working directory is not a directory: ${target.canonical}`))
+                    }),
+                )
+                yield* context.progress({ shellID: info.id })
 
-              const captureShell = Effect.fn("ShellTool.captureShell")(function* () {
-                const latest = yield* shell.output(info.id, { cursor: Number.MAX_SAFE_INTEGER })
-                const truncated = latest.size > MAX_CAPTURE_BYTES
-                const page = yield* shell.output(info.id, {
-                  cursor: Math.max(0, latest.size - MAX_CAPTURE_BYTES),
-                  limit: MAX_CAPTURE_BYTES,
+                const captureShell = Effect.fn("ShellTool.captureShell")(function* () {
+                  const latest = yield* shell.output(info.id, { cursor: Number.MAX_SAFE_INTEGER })
+                  const truncated = latest.size > MAX_CAPTURE_BYTES
+                  const page = yield* shell.output(info.id, {
+                    cursor: Math.max(0, latest.size - MAX_CAPTURE_BYTES),
+                    limit: MAX_CAPTURE_BYTES,
+                  })
+                  const notice = truncated ? `\n\n[output truncated; full output saved to: ${info.file}]` : ""
+                  return {
+                    output: `${page.output || "(no output)"}${notice}`,
+                    truncated,
+                  }
                 })
-                const notice = truncated ? `\n\n[output truncated; full output saved to: ${info.file}]` : ""
-                return {
-                  output: `${page.output || "(no output)"}${notice}`,
-                  truncated,
-                }
-              })
 
-              const settleShell = Effect.fn("ShellTool.settleShell")(function* () {
-                const final = yield* shell.wait(info.id)
-                const capture = yield* captureShell()
+                const settleShell = Effect.fn("ShellTool.settleShell")(function* () {
+                  const final = yield* shell.wait(info.id)
+                  const capture = yield* captureShell()
+
+                  // `exit` is optionalKey in the Output schema; a present-but-undefined key
+                  // fails output encoding, so omit it when the process has no exit code.
+                  if (final.status === "timeout") {
+                    return {
+                      ...(final.exit !== undefined ? { exit: final.exit } : {}),
+                      output: `${capture.output}\n\nCommand exceeded timeout of ${finalTimeout} ms. Retry with a larger timeout if the command is expected to take longer.`,
+                      truncated: capture.truncated,
+                      timeout: true,
+                      status: "completed" as const,
+                    }
+                  }
 
-                // `exit` is optionalKey in the Output schema; a present-but-undefined key
-                // fails output encoding, so omit it when the process has no exit code.
-                if (final.status === "timeout") {
                   return {
                     ...(final.exit !== undefined ? { exit: final.exit } : {}),
-                    output: `${capture.output}\n\nCommand exceeded timeout of ${finalTimeout} ms. Retry with a larger timeout if the command is expected to take longer.`,
+                    output: capture.output,
                     truncated: capture.truncated,
-                    timeout: true,
                     status: "completed" as const,
                   }
+                })
+
+                const settled = yield* Deferred.make<Output>()
+                const run = settleShell().pipe(
+                  Effect.tap((output) => Deferred.succeed(settled, output)),
+                  Effect.map((output) => output.output),
+                  Effect.onInterrupt(() => shell.remove(info.id).pipe(Effect.ignore)),
+                )
+                const job = yield* runtime.job.start({
+                  id: context.id,
+                  type: name,
+                  title: info.command,
+                  metadata: { sessionID: context.sessionID, shellID: info.id },
+                  run,
+                })
+
+                if (input.background === true) {
+                  yield* runtime.job.background(job.id)
+                  yield* notifyWhenDone(context.sessionID, context.id, info.command)
+                  return {
+                    output: BACKGROUND_STARTED,
+                    shellID: info.id,
+                    truncated: false,
+                    status: "running" as const,
+                  }
                 }
 
-                return {
-                  ...(final.exit !== undefined ? { exit: final.exit } : {}),
-                  output: capture.output,
-                  truncated: capture.truncated,
-                  status: "completed" as const,
+                const result = yield* runtime.job.block({ id: job.id, sessionID: context.sessionID }).pipe(
+                  Effect.onInterrupt(() => runtime.job.cancel(job.id).pipe(Effect.ignore)),
+                )
+                if (result?.type === "backgrounded") {
+                  yield* shell.timeout(info.id, 0)
+                  yield* notifyWhenDone(context.sessionID, context.id, info.command)
+                  return {
+                    output: BACKGROUND_STARTED,
+                    shellID: info.id,
+                    truncated: false,
+                    status: "running" as const,
+                  }
                 }
-              })
+                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"))
 
-              const settled = yield* Deferred.make<Output>()
-              const run = settleShell().pipe(
-                Effect.tap((output) => Deferred.succeed(settled, output)),
-                Effect.map((output) => output.output),
-                Effect.onInterrupt(() => shell.remove(info.id).pipe(Effect.ignore)),
-              )
-              const job = yield* runtime.job.start({
-                id: context.id,
-                type: name,
-                title: info.command,
-                metadata: { sessionID: context.sessionID, shellID: info.id },
-                run,
-              })
-
-              if (input.background === true) {
-                yield* runtime.job.background(job.id)
-                yield* notifyWhenDone(context.sessionID, context.id, info.command)
-                return {
-                  output: BACKGROUND_STARTED,
-                  shellID: info.id,
-                  truncated: false,
-                  status: "running" as const,
-                }
-              }
-
-              const result = yield* runtime.job
-                .block({ id: job.id, sessionID: context.sessionID })
-                .pipe(Effect.onInterrupt(() => runtime.job.cancel(job.id).pipe(Effect.ignore)))
-              if (result?.type === "backgrounded") {
-                yield* shell.timeout(info.id, 0)
-                yield* notifyWhenDone(context.sessionID, context.id, info.command)
-                return {
-                  output: BACKGROUND_STARTED,
-                  shellID: info.id,
-                  truncated: false,
-                  status: "running" as const,
-                }
-              }
-              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)
-            }).pipe(
-              Effect.map((output) => {
-                const content: Array<Content> = [{ type: "text", text: output.output }]
-                const model = modelOutput(output)
-                if (model) content.push({ type: "text", text: model })
-                return {
-                  output,
-                  content,
-                  metadata: {
-                    truncated: output.truncated,
-                    ...("exit" in output && output.exit !== undefined ? { exit: output.exit } : {}),
-                    ...("shellID" in output && output.shellID !== undefined ? { shellID: output.shellID } : {}),
-                    ...("timeout" in output && output.timeout !== undefined ? { timeout: output.timeout } : {}),
-                  },
-                }
-              }),
-              Effect.mapError(
-                (error) => new ToolFailure({ message: `Unable to execute command: ${input.command}`, error }),
+                return yield* Deferred.await(settled)
+              }).pipe(
+                Effect.map((output) => {
+                  const content: Array<Content> = [{ type: "text", text: output.output }]
+                  const model = modelOutput(output)
+                  if (model) content.push({ type: "text", text: model })
+                  return {
+                    output,
+                    content,
+                    metadata: {
+                      truncated: output.truncated,
+                      ...("exit" in output && output.exit !== undefined ? { exit: output.exit } : {}),
+                      ...("shellID" in output && output.shellID !== undefined ? { shellID: output.shellID } : {}),
+                      ...("timeout" in output && output.timeout !== undefined ? { timeout: output.timeout } : {}),
+                    },
+                  }
+                }),
+                Effect.mapError(
+                  (error) => new ToolFailure({ message: `Unable to execute command: ${input.command}`, error }),
+                ),
               ),
-            ),
-        }),
+          }),
+        ),
       )
       .pipe(Effect.orDie)
 

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

@@ -54,52 +54,59 @@ export const Plugin = {
 
     yield* ctx.tool
       .transform((draft) =>
-        draft.add({
-          name,
-          options: { codemode: false, permission: "edit" },
-          description:
-            "Writes a file to the local filesystem, overwriting if one exists.\n\nMissing parent directories are created automatically.\n\nUse this tool to create new files or overwrite existing files. For partial changes, use the edit tool instead.",
-          input: Input,
-          output: Output,
-          execute: (input, context) =>
-            Effect.gen(function* () {
-              const source = {
-                type: "tool" as const,
-                messageID: context.messageID,
-                id: context.id,
-              }
-              const target = yield* mutation.resolve({ path: input.path, kind: "file" })
-              const external = target.externalDirectory
-              if (external)
-                yield* permission.assert({
-                  ...LocationMutation.externalDirectoryPermission(external),
-                  sessionID: context.sessionID,
-                  agent: context.agent,
-                  source,
-                })
-              const current = yield* Bom.readFile(fs, target.absolute).pipe(
-                Effect.catchReason("PlatformError", "NotFound", () => Effect.succeed(undefined)),
-              )
-              const next = Bom.split(input.content)
-              const preview = fileDiff(target.resource, current?.text ?? "", next.text, current ? "modified" : "added")
-              yield* permission.assert({
-                action: "edit",
-                resources: [target.resource],
-                save: ["*"],
-                metadata: { files: [preview] },
-                sessionID: context.sessionID,
-                agent: context.agent,
-                source,
-              })
-              const result = yield* files.writeTextPreservingBom({ target, content: input.content })
-              const bom = (yield* Bom.readFile(fs, target.absolute)).bom
-              if (yield* formatter.file(target.absolute)) yield* Bom.syncFile(fs, target.absolute, bom)
-              return result
-            }).pipe(
-              Effect.map((output) => ({ output, content: toModelOutput(output) })),
-              Effect.mapError((error) => new ToolFailure({ message: `Unable to write ${input.path}`, error })),
-            ),
-        }),
+        draft.add(
+          ({
+              name,
+              options: { codemode: false, permission: "edit" },
+              description:
+                "Writes a file to the local filesystem, overwriting if one exists.\n\nMissing parent directories are created automatically.\n\nUse this tool to create new files or overwrite existing files. For partial changes, use the edit tool instead.",
+              input: Input,
+              output: Output,
+              execute: (input, context) =>
+                Effect.gen(function* () {
+                  const source = {
+                    type: "tool" as const,
+                    messageID: context.messageID,
+                    id: context.id,
+                  }
+                  const target = yield* mutation.resolve({ path: input.path, kind: "file" })
+                  const external = target.externalDirectory
+                  if (external)
+                    yield* permission.assert({
+                      ...LocationMutation.externalDirectoryPermission(external),
+                      sessionID: context.sessionID,
+                      agent: context.agent,
+                      source,
+                    })
+                  const current = yield* Bom.readFile(fs, target.canonical).pipe(
+                    Effect.catchReason("PlatformError", "NotFound", () => Effect.succeed(undefined)),
+                  )
+                  const next = Bom.split(input.content)
+                  const preview = fileDiff(
+                    target.resource,
+                    current?.text ?? "",
+                    next.text,
+                    current ? "modified" : "added",
+                  )
+                  yield* permission.assert({
+                    action: "edit",
+                    resources: [target.resource],
+                    save: ["*"],
+                    metadata: { files: [preview] },
+                    sessionID: context.sessionID,
+                    agent: context.agent,
+                    source,
+                  })
+                  const result = yield* files.writeTextPreservingBom({ target, content: input.content })
+                  const bom = (yield* Bom.readFile(fs, target.canonical)).bom
+                  if (yield* formatter.file(target.canonical)) yield* Bom.syncFile(fs, target.canonical, bom)
+                  return result
+                }).pipe(
+                  Effect.map((output) => ({ output, content: toModelOutput(output) })),
+                  Effect.mapError((error) => new ToolFailure({ message: `Unable to write ${input.path}`, error })),
+                ),
+            }),
+        ),
       )
       .pipe(Effect.orDie)
   }),

packages/core/src/tool/read-filesystem.ts

@@ -34,6 +34,14 @@ export class MediaIngestLimitError extends Schema.TaggedErrorClass<MediaIngestLi
   }
 }
 
+export class MalformedUtf8Error extends Schema.TaggedErrorClass<MalformedUtf8Error>()("ReadTool.MalformedUtf8Error", {
+  resource: Schema.String,
+}) {
+  override get message() {
+    return `File is not valid UTF-8: ${this.resource}`
+  }
+}
+
 export class OffsetOutOfRangeError extends Schema.TaggedErrorClass<OffsetOutOfRangeError>()(
   "ReadTool.OffsetOutOfRangeError",
   { offset: Schema.Number },
@@ -53,7 +61,13 @@ export class PathKindError extends Schema.TaggedErrorClass<PathKindError>()("Rea
 }
 
 export type InspectError = FSUtil.Error | PathKindError
-export type ReadError = FSUtil.Error | BinaryFileError | MediaIngestLimitError | OffsetOutOfRangeError | PathKindError
+export type ReadError =
+  | FSUtil.Error
+  | BinaryFileError
+  | MediaIngestLimitError
+  | MalformedUtf8Error
+  | OffsetOutOfRangeError
+  | PathKindError
 
 export const PageInput = Schema.Struct({
   offset: Schema.optionalKey(NonNegativeInt),
@@ -76,15 +90,9 @@ export class TextPage extends Schema.Class<TextPage>("ReadTool.TextPage")({
   next: Schema.optionalKey(PositiveInt),
 }) {}
 
-export interface ListEntry extends Schema.Schema.Type<typeof ListEntry> {}
-export const ListEntry = Schema.Struct({
-  path: RelativePath,
-  type: Schema.Literals(["file", "directory", "symlink"]),
-}).annotate({ identifier: "ReadTool.ListEntry" })
-
 export class ListPage extends Schema.Class<ListPage>("ReadTool.ListPage")({
   type: Schema.Literal("list-page"),
-  entries: Schema.Array(ListEntry),
+  entries: Schema.Array(FileSystem.Entry),
   truncated: Schema.Boolean,
   next: Schema.optionalKey(PositiveInt),
 }) {}
@@ -101,6 +109,36 @@ export interface Interface {
 
 export class Service extends Context.Service<Service, Interface>()("@opencode/ReadToolFileSystem") {}
 
+const extensions = new Set([
+  ".zip",
+  ".tar",
+  ".gz",
+  ".exe",
+  ".dll",
+  ".so",
+  ".class",
+  ".jar",
+  ".war",
+  ".7z",
+  ".doc",
+  ".docx",
+  ".xls",
+  ".xlsx",
+  ".ppt",
+  ".pptx",
+  ".odt",
+  ".ods",
+  ".odp",
+  ".bin",
+  ".dat",
+  ".obj",
+  ".o",
+  ".a",
+  ".lib",
+  ".wasm",
+  ".pyc",
+  ".pyo",
+])
 const startsWith = (bytes: Uint8Array, prefix: number[]) => prefix.every((value, index) => bytes[index] === value)
 const mediaMime = (bytes: Uint8Array) => {
   if (startsWith(bytes, [0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a])) return "image/png"
@@ -110,7 +148,8 @@ const mediaMime = (bytes: Uint8Array) => {
     return "image/webp"
   if (startsWith(bytes, [0x25, 0x50, 0x44, 0x46, 0x2d])) return "application/pdf"
 }
-const binary = (bytes: Uint8Array) => {
+const binary = (resource: string, bytes: Uint8Array) => {
+  if (extensions.has(path.extname(resource).toLowerCase())) return true
   if (bytes.length === 0) return false
   let nonPrintable = 0
   for (const byte of bytes) {
@@ -119,9 +158,16 @@ const binary = (bytes: Uint8Array) => {
   }
   return nonPrintable / bytes.length > 0.3
 }
-const decodeUtf8 = (decoder: TextDecoder, bytes?: Uint8Array) => decoder.decode(bytes, { stream: bytes !== undefined })
+const decodeUtf8 = (resource: string, decoder: TextDecoder, bytes?: Uint8Array) =>
+  Effect.try({
+    try: () => decoder.decode(bytes, { stream: bytes !== undefined }),
+    catch: (error) => {
+      if (error instanceof TypeError) return new MalformedUtf8Error({ resource })
+      throw error
+    },
+  })
 const decodeChunk = (resource: string, decoder: TextDecoder, bytes: Uint8Array) =>
-  bytes.includes(0) ? Effect.fail(new BinaryFileError({ resource })) : Effect.succeed(decodeUtf8(decoder, bytes))
+  bytes.includes(0) ? Effect.fail(new BinaryFileError({ resource })) : decodeUtf8(resource, decoder, bytes)
 
 export const inspect = Effect.fn("ReadTool.inspect")(function* (fs: FSUtil.Interface, input: string) {
   const info = yield* fs.stat(input)
@@ -172,17 +218,19 @@ export const read = Effect.fn("ReadTool.read")(function* (
           mime,
         }
       }
+      if (extensions.has(path.extname(resource).toLowerCase()))
+        return yield* Effect.fail(new BinaryFileError({ resource }))
       const paged = info.size > MAX_READ_BYTES || page.offset !== undefined || page.limit !== undefined
       if (!paged) {
-        if (binary(first)) return yield* Effect.fail(new BinaryFileError({ resource }))
-        const decoder = new TextDecoder()
-        const text = [decodeUtf8(decoder, first)]
+        if (binary(resource, first)) return yield* Effect.fail(new BinaryFileError({ resource }))
+        const decoder = new TextDecoder("utf-8", { fatal: true })
+        const text = [yield* decodeUtf8(resource, decoder, first)]
         while (true) {
           const chunk = yield* file.readAlloc(64 * 1024)
           if (Option.isNone(chunk)) break
           text.push(yield* decodeChunk(resource, decoder, chunk.value))
         }
-        text.push(decodeUtf8(decoder))
+        text.push(yield* decodeUtf8(resource, decoder))
         return {
           type: "file" as const,
           uri: pathToFileURL(real).href,
@@ -195,7 +243,7 @@ export const read = Effect.fn("ReadTool.read")(function* (
       const offset = page.offset || 1
       const limit = Math.min(page.limit || MAX_READ_LINES, MAX_READ_LINES)
       const lines: string[] = []
-      const decoder = new TextDecoder()
+      const decoder = new TextDecoder("utf-8", { fatal: true })
       let pending = ""
       let discard = false
       let line = 1
@@ -253,8 +301,8 @@ export const read = Effect.fn("ReadTool.read")(function* (
           const newline = chunk.indexOf(10, start)
           const end = newline === -1 ? chunk.length : newline + 1
           const segment = chunk.subarray(start, end)
-          if (binary(segment)) return yield* Effect.fail(new BinaryFileError({ resource }))
-          if (!consume(decodeUtf8(decoder, segment))) return false
+          if (binary(resource, segment)) return yield* Effect.fail(new BinaryFileError({ resource }))
+          if (!consume(yield* decodeUtf8(resource, decoder, segment))) return false
           start = end
         }
         return true
@@ -266,7 +314,7 @@ export const read = Effect.fn("ReadTool.read")(function* (
         done = !(yield* consumeChunk(chunk.value))
       }
       if (!done) {
-        const tail = decodeUtf8(decoder)
+        const tail = yield* decodeUtf8(resource, decoder)
         if (!discard) pending += tail
         if (pending) append(pending.endsWith("\r") ? pending.slice(0, -1) : pending)
       }
@@ -288,26 +336,26 @@ export const list = Effect.fn("ReadTool.list")(function* (fs: FSUtil.Interface,
   const items = yield* fs.readDirectoryEntries(real)
   const offset = page.offset || 1
   const limit = Math.min(page.limit || MAX_READ_LINES, MAX_READ_LINES)
-  const visible = items
-    .flatMap((item) =>
-      item.type === "other"
-        ? []
-        : [
-            ListEntry.make({
-              path: RelativePath.make(item.name + (item.type === "directory" ? path.sep : "")),
-              type: item.type,
-            }),
-          ],
-    )
-    .sort((a, b) =>
-      a.type === "directory"
-        ? b.type === "directory"
-          ? a.path.localeCompare(b.path)
-          : -1
-        : b.type === "directory"
-          ? 1
-          : a.path.localeCompare(b.path),
-    )
+  const entries = yield* Effect.forEach(
+    items,
+    (item) =>
+      Effect.gen(function* () {
+        const absolute = path.join(real, item.name)
+        const target = yield* fs.realPath(absolute).pipe(Effect.catch(() => Effect.void))
+        if (!target || !FSUtil.contains(real, target)) return
+        const info = yield* fs.stat(target).pipe(Effect.catch(() => Effect.void))
+        const type = info?.type === "Directory" ? "directory" : info?.type === "File" ? "file" : undefined
+        if (!type) return
+        return FileSystem.Entry.make({
+          path: RelativePath.make(item.name + (type === "directory" ? path.sep : "")),
+          type,
+        })
+      }),
+    { concurrency: 16 },
+  )
+  const visible = entries
+    .filter((item): item is FileSystem.Entry => item !== undefined)
+    .sort((a, b) => (a.type === b.type ? a.path.localeCompare(b.path) : a.type === "directory" ? -1 : 1))
   const selected = visible.slice(offset - 1, offset - 1 + limit)
   const truncated = offset - 1 + selected.length < visible.length
   return new ListPage({

packages/core/src/v1/config/migrate.ts

@@ -119,16 +119,8 @@ function agents(info: typeof ConfigV1.Info.Type) {
     ...Object.entries(info.agent ?? {}),
     ...Object.entries(info.mode ?? {}).map(([name, agent]) => [name, { ...agent, mode: "primary" as const }] as const),
   ]
-  const result = Object.fromEntries(entries.flatMap(([name, agent]) => (agent ? [[name, migrateAgent(agent)]] : [])))
-  const small = modelSelection(info.small_model)
-  if (!small) return entries.length ? result : undefined
-  return {
-    ...result,
-    title: {
-      model: small,
-      ...result.title,
-    },
-  }
+  if (!entries.length) return undefined
+  return Object.fromEntries(entries.flatMap(([name, agent]) => (agent ? [[name, migrateAgent(agent)]] : [])))
 }
 
 export function migrateAgent(info: ConfigAgentV1.Info) {

packages/core/test/agent.test.ts

@@ -126,7 +126,6 @@ describe("Agent", () => {
 
       yield* agent.transform((editor) => editor.update(id, () => {}))
       const info = yield* agent.get(id)
-      expect(info?.mode).toBe("primary")
       expect(info?.permissions.slice(0, Agent.Info.default(id).permissions.length)).toEqual(
         Agent.Info.default(id).permissions,
       )

packages/core/test/config/config.test.ts

@@ -512,20 +512,6 @@ describe("Config", () => {
     }),
   )
 
-  it.effect("migrates the v1 small model to the title agent", () =>
-    Effect.sync(() => {
-      expect(
-        ConfigMigrateV1.migrate({
-          small_model: "anthropic/claude-haiku-4-5",
-          agent: { title: { prompt: "Custom title prompt" } },
-        }).agents?.title,
-      ).toEqual({
-        model: { providerID: "anthropic", model: "claude-haiku-4-5" },
-        system: "Custom title prompt",
-      })
-    }),
-  )
-
   it.effect("migrates v1 provider lists to policies", () =>
     Effect.sync(() => {
       expect(

packages/core/test/config/normalization.test.ts

@@ -149,28 +149,6 @@ describe("ConfigNormalize", () => {
     expect(() => Schema.decodeUnknownSync(Info)(result.encoded)).not.toThrow()
   })
 
-  test("migrates the legacy small model to the title agent", () => {
-    const result = normalized({
-      small_model: "anthropic/claude-haiku-4-5",
-      agent: { title: { prompt: "Custom title prompt" } },
-    })
-    expect(result.encoded.agents).toEqual({
-      title: {
-        model: { providerID: "anthropic", model: "claude-haiku-4-5" },
-        system: "Custom title prompt",
-      },
-    })
-    expect(result.diagnostics).toEqual([])
-  })
-
-  test("omits an invalid legacy small model without exposing its value", () => {
-    const secret = "do-not-log-this-value"
-    const result = normalized({ small_model: secret })
-    expect(result.encoded.agents).toBeUndefined()
-    expect(result.diagnostics.map((item) => [item.kind, item.path])).toEqual([["unsupported", ["small_model"]]])
-    expect(JSON.stringify(result.diagnostics)).not.toContain(secret)
-  })
-
   test("recovers malformed named entries and retains a valid legacy collision", () => {
     const result = normalized({
       command: { fallback: { template: "legacy" } },
@@ -412,6 +390,7 @@ describe("ConfigNormalize", () => {
     const secret = "do-not-log-this-value"
     const result = normalized({
       logLevel: "DEBUG",
+      small_model: secret,
       agent: { reviewer: { name: secret, prompt: "review" } },
       provider: {
         custom: {
@@ -430,6 +409,7 @@ describe("ConfigNormalize", () => {
     })
     expect(result.diagnostics.filter((item) => item.kind === "unsupported").map((item) => item.path)).toEqual([
       ["logLevel"],
+      ["small_model"],
       ["agent", "reviewer", "name"],
       ["provider", "custom", "id"],
       ["provider", "custom", "whitelist"],

packages/core/test/file-mutation.test.ts

@@ -43,7 +43,7 @@ describe("FileMutation", () => {
 
         expect(yield* (yield* FileMutation.Service).write({ target, content: "after" })).toEqual({
           operation: "write",
-          target: target.absolute,
+          target: target.canonical,
           resource: "hello.txt",
           existed: true,
         })
@@ -62,11 +62,11 @@ describe("FileMutation", () => {
 
         expect(result).toEqual({
           operation: "write",
-          target: target.absolute,
+          target: target.canonical,
           resource: "src/nested/hello.txt",
           existed: false,
         })
-        expect(yield* Effect.promise(() => fs.readFile(target.absolute, "utf8"))).toBe("hello")
+        expect(yield* Effect.promise(() => fs.readFile(result.target, "utf8"))).toBe("hello")
       }).pipe(provide(directory)),
     ),
   )
@@ -84,7 +84,7 @@ describe("FileMutation", () => {
         yield* files.writeTextPreservingBom({ target: created, content: "\uFEFF\uFEFF\uFEFFcreated" })
 
         expect(yield* Effect.promise(() => fs.readFile(preservedPath, "utf8"))).toBe("\uFEFFafter")
-        expect(yield* Effect.promise(() => fs.readFile(created.absolute, "utf8"))).toBe("\uFEFFcreated")
+        expect(yield* Effect.promise(() => fs.readFile(created.canonical, "utf8"))).toBe("\uFEFFcreated")
       }).pipe(provide(directory)),
     ),
   )
@@ -99,7 +99,7 @@ describe("FileMutation", () => {
 
           expect(result).toEqual({
             operation: "write",
-            target: target.absolute,
+            target: target.canonical,
             resource: target.resource,
             existed: false,
           })
@@ -109,7 +109,7 @@ describe("FileMutation", () => {
     ),
   )
 
-  it.live("serializes concurrent writes to the same absolute target", () =>
+  it.live("serializes concurrent writes to the same canonical target", () =>
     withTmp((directory) =>
       Effect.gen(function* () {
         const targetPath = path.join(directory, "shared.txt")
@@ -152,7 +152,7 @@ describe("FileMutation", () => {
     ),
   )
 
-  it.live("allows distinct absolute targets to proceed independently", () =>
+  it.live("allows distinct canonical targets to proceed independently", () =>
     withTmp((directory) =>
       Effect.gen(function* () {
         const firstStarted = yield* Deferred.make<void>()

packages/core/test/location-mutation.test.ts

@@ -37,7 +37,7 @@ describe("LocationMutation", () => {
         const target = yield* (yield* LocationMutation.Service).resolve({ path: "hello.txt" })
 
         expect(target).toMatchObject({
-          absolute: targetPath,
+          canonical: yield* Effect.promise(() => fs.realpath(targetPath)),
           resource: "hello.txt",
         })
         expect(target.externalDirectory).toBeUndefined()
@@ -50,8 +50,10 @@ describe("LocationMutation", () => {
       Effect.gen(function* () {
         yield* Effect.promise(() => fs.mkdir(path.join(directory, "src")))
         const target = yield* (yield* LocationMutation.Service).resolve({ path: path.join("src", "new.txt") })
+        const root = yield* Effect.promise(() => fs.realpath(directory))
+
         expect(target).toMatchObject({
-          absolute: path.join(directory, "src", "new.txt"),
+          canonical: path.join(root, "src", "new.txt"),
           resource: "src/new.txt",
         })
       }).pipe(provide(directory)),
@@ -62,9 +64,9 @@ describe("LocationMutation", () => {
     withTmp((directory) =>
       Effect.gen(function* () {
         const target = yield* (yield* LocationMutation.Service).resolve({ path: "../outside.txt" })
-        const root = path.dirname(directory)
+        const root = yield* Effect.promise(() => fs.realpath(path.dirname(directory)))
         expect(target).toMatchObject({
-          absolute: path.join(root, "outside.txt"),
+          canonical: path.join(root, "outside.txt"),
           resource: path.join(root, "outside.txt").replaceAll("\\", "/"),
         })
         expect(target.externalDirectory).toMatchObject({
@@ -75,7 +77,7 @@ describe("LocationMutation", () => {
     ),
   )
 
-  it.live("resolves a prospective target below an external symlink lexically", () =>
+  it.live("authorizes a prospective target below an external symlink by its in-location path", () =>
     withTmp((directory) => {
       const outside = `${directory}-outside`
       return Effect.gen(function* () {
@@ -86,7 +88,7 @@ describe("LocationMutation", () => {
         })
         const target = yield* (yield* LocationMutation.Service).resolve({ path: path.join("escape", "new.txt") })
         expect(target).toMatchObject({
-          absolute: path.join(directory, "escape", "new.txt"),
+          canonical: path.join(yield* Effect.promise(() => fs.realpath(outside)), "new.txt"),
           resource: "escape/new.txt",
         })
         expect(target.externalDirectory).toBeUndefined()
@@ -105,7 +107,7 @@ describe("LocationMutation", () => {
         })
 
         expect(yield* (yield* LocationMutation.Service).resolve({ path: "linked/new.txt" })).toMatchObject({
-          absolute: path.join(directory, "linked", "new.txt"),
+          canonical: path.join(yield* Effect.promise(() => fs.realpath(directory)), "actual", "new.txt"),
           resource: "linked/new.txt",
         })
       }).pipe(provide(directory)),
@@ -118,7 +120,7 @@ describe("LocationMutation", () => {
         const targetPath = path.join(directory, "new.txt")
         const target = yield* (yield* LocationMutation.Service).resolve({ path: targetPath })
         expect(target).toMatchObject({
-          absolute: targetPath,
+          canonical: path.join(yield* Effect.promise(() => fs.realpath(directory)), "new.txt"),
           resource: "new.txt",
         })
         expect(target.externalDirectory).toBeUndefined()
@@ -132,9 +134,9 @@ describe("LocationMutation", () => {
         Effect.gen(function* () {
           const targetPath = path.join(outside, "new.txt")
           const target = yield* (yield* LocationMutation.Service).resolve({ path: targetPath })
-          const root = outside
+          const root = yield* Effect.promise(() => fs.realpath(outside))
           expect(target).toMatchObject({
-            absolute: path.join(root, "new.txt"),
+            canonical: path.join(root, "new.txt"),
             resource: path.join(root, "new.txt").replaceAll("\\", "/"),
           })
           expect(target.externalDirectory).toMatchObject({
@@ -153,23 +155,24 @@ describe("LocationMutation", () => {
           const targetPath = path.join(outside, "existing.txt")
           yield* Effect.promise(() => fs.writeFile(targetPath, "existing"))
           const target = yield* (yield* LocationMutation.Service).resolve({ path: targetPath })
-          expect(target).toMatchObject({ absolute: targetPath })
-          expect(target.externalDirectory?.directory).toBe(outside)
+          const root = yield* Effect.promise(() => fs.realpath(outside))
+          expect(target).toMatchObject({ canonical: path.join(root, "existing.txt") })
+          expect(target.externalDirectory?.directory).toBe(root)
         }).pipe(provide(directory)),
       ),
     ),
   )
 
-  it.live("authorizes prospective external descendants at their lexical parent", () =>
+  it.live("anchors prospective external descendants at their stable existing directory", () =>
     withTmp((directory) =>
       withTmp((outside) =>
         Effect.gen(function* () {
           const targetPath = path.join(outside, "new", "nested", "file.txt")
           const target = yield* (yield* LocationMutation.Service).resolve({ path: targetPath })
-          const parent = path.dirname(targetPath)
+          const root = yield* Effect.promise(() => fs.realpath(outside))
           expect(target.externalDirectory).toMatchObject({
-            directory: parent,
-            resource: path.join(parent, "*").replaceAll("\\", "/"),
+            directory: root,
+            resource: path.join(root, "*").replaceAll("\\", "/"),
           })
         }).pipe(provide(directory)),
       ),

packages/core/test/session-runner.test.ts

@@ -2440,6 +2440,30 @@ describe("SessionRunnerLLM", () => {
     }),
   )
 
+  it.effect("continues after an unknown finish containing a local tool call", () =>
+    Effect.gen(function* () {
+      const session = yield* setup
+      yield* admit(session, "Echo this")
+      yield* TestLLM.push(
+        TestLLM.complete(
+          { reason: { normalized: "unknown" } },
+          LLMEvent.toolCall({ id: "call-echo", name: "echo", input: { text: "hello" } }),
+        ),
+        TestLLM.text("Done", "text-final"),
+      )
+
+      yield* session.resume(sessionID)
+
+      expect(requests).toHaveLength(2)
+      expect(executions).toEqual(["hello"])
+      expect(yield* session.context(sessionID)).toMatchObject([
+        { type: "user", text: "Echo this" },
+        { type: "assistant", finish: "unknown", content: [{ type: "tool", state: { status: "completed" } }] },
+        { type: "assistant", finish: "stop", content: [{ type: "text", text: "Done" }] },
+      ])
+    }),
+  )
+
   it.effect("reloads a model switch before a tool-driven continuation step", () =>
     Effect.gen(function* () {
       const session = yield* setup

packages/core/test/tool-read-filesystem.test.ts

@@ -1,5 +1,4 @@
 import { describe, expect } from "bun:test"
-import fs from "fs/promises"
 import path from "path"
 import { Effect, FileSystem } from "effect"
 import { LayerNodePlatform } from "@opencode-ai/util/effect/app-node-platform"
@@ -51,53 +50,22 @@ describe("ReadToolFileSystem", () => {
     }),
   )
 
-  it.effect("reads malformed UTF-8 lossily and still rejects null-byte binary content", () =>
+  it.effect("reports binary and malformed UTF-8 content as typed errors", () =>
     Effect.gen(function* () {
       const { fs, files, directory } = yield* fixture
       const binary = path.join(directory, "archive.dat")
       const malformed = path.join(directory, "malformed.txt")
       yield* files.writeFile(binary, Uint8Array.of(0, 1, 2, 3))
-      yield* files.writeFile(malformed, Uint8Array.of(0x68, 0x69, 0x80))
+      const malformedContent = new Uint8Array(64 * 1024 + 1).fill(97)
+      malformedContent[64 * 1024] = 0x80
+      yield* files.writeFile(malformed, malformedContent)
 
       const binaryError = yield* ReadToolFileSystem.read(fs, binary, "archive.dat").pipe(Effect.flip)
-      const malformedResult = yield* ReadToolFileSystem.read(fs, malformed, "malformed.txt")
+      const malformedError = yield* ReadToolFileSystem.read(fs, malformed, "malformed.txt").pipe(Effect.flip)
 
       expect(binaryError).toBeInstanceOf(ReadToolFileSystem.BinaryFileError)
       expect(binaryError.message).toBe("Cannot read binary file: archive.dat")
-      expect(malformedResult).toMatchObject({ type: "file", content: "hi\uFFFD", encoding: "utf8" })
-    }),
-  )
-
-  it.effect("reads text despite a binary-associated extension", () =>
-    Effect.gen(function* () {
-      const { fs, files, directory } = yield* fixture
-      const file = path.join(directory, "notes.docx")
-      yield* files.writeFileString(file, "plain text")
-
-      const result = yield* ReadToolFileSystem.read(fs, file, "notes.docx")
-
-      expect(result).toMatchObject({ type: "file", content: "plain text", encoding: "utf8" })
-    }),
-  )
-
-  it.effect("lists unresolved symlinks, including broken and escaping links", () =>
-    Effect.gen(function* () {
-      if (process.platform === "win32") return
-      const { fs: service, files, directory } = yield* fixture
-      const outside = yield* files.makeTempDirectoryScoped()
-      yield* files.makeDirectory(path.join(directory, "folder"))
-      yield* files.writeFileString(path.join(directory, "file.txt"), "hello")
-      yield* Effect.promise(() => fs.symlink(path.join(outside, "target.txt"), path.join(directory, "escape")))
-      yield* Effect.promise(() => fs.symlink(path.join(directory, "missing.txt"), path.join(directory, "broken")))
-
-      const result = yield* ReadToolFileSystem.list(service, directory)
-
-      expect(result.entries.map((entry) => ({ ...entry, path: String(entry.path) }))).toEqual([
-        { path: `folder${path.sep}`, type: "directory" },
-        { path: "broken", type: "symlink" },
-        { path: "escape", type: "symlink" },
-        { path: "file.txt", type: "file" },
-      ])
+      expect(malformedError).toBeInstanceOf(ReadToolFileSystem.MalformedUtf8Error)
     }),
   )
 

packages/core/test/tool-read.test.ts

@@ -148,13 +148,13 @@ const mutation = Layer.succeed(
   LocationMutation.Service,
   LocationMutation.Service.of({
     resolve: (input) => {
-      const absolute = path.resolve(process.cwd(), input.path)
-      const external = path.isAbsolute(input.path) && !FSUtil.contains(process.cwd(), absolute)
-      const resource = external ? absolute.replaceAll("\\", "/") : path.relative(process.cwd(), absolute) || "."
-      const directory = path.dirname(absolute)
+      const canonical = path.resolve(process.cwd(), input.path)
+      const external = path.isAbsolute(input.path) && !FSUtil.contains(process.cwd(), canonical)
+      const resource = external ? canonical.replaceAll("\\", "/") : path.relative(process.cwd(), canonical) || "."
+      const directory = path.dirname(canonical)
       const externalResource = path.join(directory, "*").replaceAll("\\", "/")
       return Effect.succeed({
-        absolute,
+        canonical,
         resource,
         externalDirectory: external
           ? {
@@ -621,6 +621,10 @@ describe("ReadTool", () => {
     Effect.gen(function* () {
       const registry = yield* Tool.Service
       for (const [error, message] of [
+        [
+          new ReadToolFileSystem.MalformedUtf8Error({ resource: "invalid.txt" }),
+          "File is not valid UTF-8: invalid.txt",
+        ],
         [new ReadToolFileSystem.OffsetOutOfRangeError({ offset: 10 }), "Offset 10 is out of range"],
         [
           new ReadToolFileSystem.PathKindError({ resource: "socket", expected: "a file" }),
@@ -717,19 +721,16 @@ describe("ReadTool", () => {
       const registry = yield* Tool.Service
 
       const result = yield* executeTool(registry, {
-        sessionID,
-        ...toolIdentity,
-        call: {
-          type: "tool-call",
-          id: "call-read-directory",
-          name: "read",
-          input: { path: "src", offset: 2, limit: 10 },
-        },
-      })
-      expect(result).toMatchObject({
-        status: "completed",
-        output: { entries: listResult.entries, truncated: true, next: 4 },
-      })
+          sessionID,
+          ...toolIdentity,
+          call: {
+            type: "tool-call",
+            id: "call-read-directory",
+            name: "read",
+            input: { path: "src", offset: 2, limit: 10 },
+          },
+        })
+      expect(result).toMatchObject({ status: "completed", output: { entries: listResult.entries, truncated: true, next: 4 } })
       if (result.status !== "completed") return
       expect(result.content).toEqual([
         {

packages/core/test/tool-write.test.ts

@@ -90,7 +90,13 @@ const withTool = <A, E, R>(directory: string, body: (registry: Tool.Interface) =
   }).pipe(
     Effect.provide(
       AppNodeBuilder.build(
-        LayerNode.group([Tool.node, Tool.node, LocationMutation.node, FileMutation.node, writeToolNode]),
+        LayerNode.group([
+          Tool.node,
+          Tool.node,
+          LocationMutation.node,
+          FileMutation.node,
+          writeToolNode,
+        ]),
         [
           [FSUtil.node, filesystem],
           [Location.node, activeLocation],
@@ -224,10 +230,7 @@ describe("WriteTool", () => {
         const deduplicated = path.join(tmp.path, "deduplicated.txt")
         formatFile = (target) =>
           Effect.promise(async () => {
-            await fs.writeFile(
-              target,
-              `\uFEFF\uFEFF\uFEFF${(await fs.readFile(target, "utf8")).replace(/^\uFEFF+/, "")}`,
-            )
+            await fs.writeFile(target, `\uFEFF\uFEFF\uFEFF${(await fs.readFile(target, "utf8")).replace(/^\uFEFF+/, "")}`)
             return true
           })
         return Effect.promise(() =>
@@ -320,22 +323,24 @@ describe("WriteTool", () => {
         ).pipe(
           Effect.andThen((settled) =>
             Effect.gen(function* () {
-              const absoluteTarget = target
+              const canonicalTarget = path.join(yield* Effect.promise(() => fs.realpath(outside.path)), "external.txt")
               expect(assertions.map((input) => input.action)).toEqual(["external_directory", "edit"])
               expect(assertions[0]).toMatchObject({
-                resources: [path.join(outside.path, "*").replaceAll("\\", "/")],
+                resources: [
+                  path.join(yield* Effect.promise(() => fs.realpath(outside.path)), "*").replaceAll("\\", "/"),
+                ],
               })
-              expect(assertions[1]).toMatchObject({ resources: [absoluteTarget.replaceAll("\\", "/")], save: ["*"] })
+              expect(assertions[1]).toMatchObject({ resources: [canonicalTarget.replaceAll("\\", "/")], save: ["*"] })
               expect(settled).toMatchObject({
                 status: "completed",
                 output: {
-                  target: absoluteTarget,
-                  resource: absoluteTarget.replaceAll("\\", "/"),
+                  target: canonicalTarget,
+                  resource: canonicalTarget.replaceAll("\\", "/"),
                   existed: false,
                 },
               })
               expect(yield* Effect.promise(() => fs.readFile(target, "utf8"))).toBe("external")
-              expect(writes).toEqual([absoluteTarget])
+              expect(writes).toEqual([canonicalTarget])
             }),
           ),
         )
@@ -363,10 +368,12 @@ describe("WriteTool", () => {
           ),
           Effect.andThen(
             Effect.gen(function* () {
+              const canonicalRepo = yield* Effect.promise(() => fs.realpath(repo))
+              const canonicalNested = yield* Effect.promise(() => fs.realpath(nested))
               expect(assertions[0]).toMatchObject({
                 action: "external_directory",
-                resources: [path.join(nested, "*").replaceAll("\\", "/")],
-                save: [path.join(repo, "*").replaceAll("\\", "/")],
+                resources: [path.join(canonicalNested, "*").replaceAll("\\", "/")],
+                save: [path.join(canonicalRepo, "*").replaceAll("\\", "/")],
               })
             }),
           ),

packages/desktop/src/main/external-url.test.ts

@@ -1,18 +0,0 @@
-import { describe, expect, test } from "bun:test"
-import { isSafeExternalUrl } from "./external-url"
-
-describe("external URL policy", () => {
-  test.each(["https://opencode.ai", "http://127.0.0.1:4096", "mailto:hello@opencode.ai"])("allows %s", (url) =>
-    expect(isSafeExternalUrl(url)).toBe(true),
-  )
-
-  test.each(["file:///tmp/test", "javascript:alert(1)", "data:text/html,test", "vscode://file/tmp/test", "nope"])(
-    "rejects %s",
-    (url) => expect(isSafeExternalUrl(url)).toBe(false),
-  )
-
-  test("rejects non-string values", () => {
-    expect(isSafeExternalUrl(null)).toBe(false)
-    expect(isSafeExternalUrl({ toString: () => "https://opencode.ai" })).toBe(false)
-  })
-})

packages/desktop/src/main/external-url.ts

@@ -1,6 +0,0 @@
-const protocols = new Set(["http:", "https:", "mailto:"])
-
-export function isSafeExternalUrl(value: unknown) {
-  if (typeof value !== "string" || !URL.canParse(value)) return false
-  return protocols.has(new URL(value).protocol)
-}

packages/desktop/src/main/ipc.ts

@@ -8,7 +8,6 @@ import type { DesktopMenuAction } from "@opencode-ai/app/desktop-menu"
 import type { FatalRendererError, ServerReadyData, TitlebarTheme } from "../preload/types"
 import { runDesktopMenuAction } from "./desktop-menu-actions"
 import { setForceFocus } from "./debug"
-import { isSafeExternalUrl } from "./external-url"
 import { assertAttachmentBudget, createPickedFileAuthorizations } from "./attachment-picker"
 import { getStore, removeStoreFileIfEmpty } from "./store"
 import { getPinchZoomEnabled, getWindowID, setPinchZoomEnabled, setTitlebar, updateTitlebar } from "./windows"
@@ -179,7 +178,6 @@ export function registerIpcHandlers(deps: Deps) {
   )
 
   ipcMain.on("open-link", (_event: IpcMainEvent, url: string) => {
-    if (!isSafeExternalUrl(url)) return
     void shell.openExternal(url)
   })
 

packages/desktop/src/main/windows.ts

@@ -220,11 +220,6 @@ export function createMainWindow(id: string = randomUUID()) {
   state.manage(win)
   registerWindow(win, id)
   wireFullscreen(win)
-  win.webContents.on("will-frame-navigate", (event) => {
-    if (isRendererUrl(event.url)) return
-    event.preventDefault()
-  })
-  win.webContents.setWindowOpenHandler(() => ({ action: "deny" }))
   loadWindow(win, "index.html")
   wireZoom(win)
 

packages/schema/src/agent.ts

@@ -41,7 +41,7 @@ export const Info = Schema.Struct({
           id,
           name: Name.make(id),
           request: { settings: {}, headers: {}, body: {} },
-          mode: "primary",
+          mode: "all",
           hidden: false,
           permissions: [
             { action: "*", resource: "*", effect: "allow" },

packages/tui/src/context/data.tsx

@@ -15,7 +15,6 @@ import type {
   ModelInfo,
   PermissionSavedInfo,
   PermissionRequest,
-  PermissionReplyInput,
   Project,
   ProviderInfo,
   ReferenceInfo,
@@ -32,7 +31,6 @@ import type {
   OpenCodeEvent,
   WebSearchProvider,
 } from "@opencode-ai/client"
-import { isPermissionNotFoundError } from "@opencode-ai/client"
 import type { Plugin } from "@opencode-ai/plugin/tui"
 import { createStore, produce, reconcile } from "solid-js/store"
 import { createSimpleContext } from "./helper"
@@ -178,17 +176,6 @@ export const { use: useData, provider: DataProvider } = createSimpleContext({
       )
     }
 
-    function removePermission(sessionID: string, requestID: string) {
-      const requests = store.session.permission[sessionID]
-      if (!requests?.some((request) => request.id === requestID)) return
-      setStore(
-        "session",
-        "permission",
-        sessionID,
-        requests.filter((request) => request.id !== requestID),
-      )
-    }
-
     const message = {
       update(sessionID: string, fn: (messages: SessionMessageInfo[], index: Map<string, number>) => void) {
         setStore(
@@ -853,7 +840,14 @@ export const { use: useData, provider: DataProvider } = createSimpleContext({
           ])
           break
         case "permission.replied":
-          removePermission(event.data.sessionID, event.data.requestID)
+          setStore(
+            "session",
+            "permission",
+            event.data.sessionID,
+            (store.session.permission[event.data.sessionID] ?? []).filter(
+              (request) => request.id !== event.data.requestID,
+            ),
+          )
           break
         case "form.created":
           if (store.session.form[event.data.form.sessionID]?.some((form) => form.id === event.data.form.id)) break
@@ -1042,12 +1036,6 @@ export const { use: useData, provider: DataProvider } = createSimpleContext({
           invalidate(sessionID: string) {
             sync.invalidate(`session.permission:${sessionID}`)
           },
-          async reply(input: PermissionReplyInput) {
-            await client.api.permission.reply(input).catch((error: unknown) => {
-              if (!isPermissionNotFoundError(error)) throw error
-            })
-            removePermission(input.sessionID, input.requestID)
-          },
         },
         form: {
           list(sessionID: string, ref?: LocationRef) {

packages/tui/src/routes/session/index.tsx

@@ -227,7 +227,7 @@ export function Session() {
     permissions().forEach((request) => {
       if (autoApproved.has(request.id)) return
       autoApproved.add(request.id)
-      void data.session.permission
+      void client.api.permission
         .reply({
           sessionID: request.sessionID,
           reply: "once",

packages/tui/src/routes/session/permission.tsx

@@ -3,7 +3,8 @@ import { createMemo, For, Match, Show, Switch } from "solid-js"
 import { Portal, useRenderer, useTerminalDimensions, type JSX } from "@opentui/solid"
 import type { TextareaRenderable } from "@opentui/core"
 import { useTheme, useThemes } from "../../context/theme"
-import type { PermissionReply, PermissionRequest } from "@opencode-ai/client"
+import type { PermissionRequest } from "@opencode-ai/client"
+import { useClient } from "../../context/client"
 import { SplitBorder } from "../../ui/border"
 import { useData } from "../../context/data"
 import { filetype } from "../../util/filetype"
@@ -14,7 +15,6 @@ import { Keymap } from "../../context/keymap"
 import { usePathFormatter } from "../../context/path-format"
 import { SimulationSemantics } from "../../simulation/semantics"
 import { PatchDiff } from "../../component/patch-diff"
-import { useToast } from "../../ui/toast"
 
 type PermissionStage = "permission" | "always" | "reject"
 
@@ -110,8 +110,8 @@ function EditBody(props: { file?: string; diff?: string; patch?: string }) {
 }
 
 export function PermissionPrompt(props: { request: PermissionRequest; directory?: string }) {
+  const client = useClient()
   const data = useData()
-  const toast = useToast()
   const [store, setStore] = createStore({
     stage: "permission" as PermissionStage,
   })
@@ -132,12 +132,6 @@ export function PermissionPrompt(props: { request: PermissionRequest; directory?
 
   const theme = useTheme()
 
-  function reply(value: PermissionReply, message?: string) {
-    void data.session.permission
-      .reply({ sessionID: props.request.sessionID, requestID: props.request.id, reply: value, message })
-      .catch((error: unknown) => toast.error(error))
-  }
-
   return (
     <Switch>
       <Match when={store.stage === "always"}>
@@ -157,7 +151,11 @@ export function PermissionPrompt(props: { request: PermissionRequest; directory?
           onSelect={(option) => {
             setStore("stage", "permission")
             if (option === "cancel") return
-            reply("always")
+            void client.api.permission.reply({
+              sessionID: props.request.sessionID,
+              reply: "always",
+              requestID: props.request.id,
+            })
           }}
         />
       </Match>
@@ -166,7 +164,12 @@ export function PermissionPrompt(props: { request: PermissionRequest; directory?
           action={props.request.action}
           instance={props.request.id}
           onConfirm={(message) => {
-            reply("reject", message || undefined)
+            void client.api.permission.reply({
+              sessionID: props.request.sessionID,
+              reply: "reject",
+              requestID: props.request.id,
+              message: message || undefined,
+            })
           }}
           onCancel={() => {
             setStore("stage", "permission")
@@ -262,10 +265,18 @@ export function PermissionPrompt(props: { request: PermissionRequest; directory?
                     setStore("stage", "reject")
                     return
                   }
-                  reply("reject")
+                  void client.api.permission.reply({
+                    sessionID: props.request.sessionID,
+                    reply: "reject",
+                    requestID: props.request.id,
+                  })
                   return
                 }
-                reply("once")
+                void client.api.permission.reply({
+                  sessionID: props.request.sessionID,
+                  reply: "once",
+                  requestID: props.request.id,
+                })
               }}
             />
           )

packages/tui/test/cli/tui/data.test.tsx

@@ -2067,64 +2067,6 @@ test("reconciles active session permissions when the event stream reconnects", a
   }
 })
 
-test("dismisses a permission that expired before its reply", async () => {
-  const events = createEventStream()
-  const request = { id: "per_stale", sessionID: "ses_active", action: "read", resources: ["old.txt"] }
-  let replies = 0
-  const calls = createFetch((url, init) => {
-    if (url.pathname === "/api/session/ses_active/permission/per_stale/reply" && init.method === "POST") {
-      replies++
-      return json(
-        {
-          _tag: "PermissionNotFoundError",
-          requestID: request.id,
-          message: `Permission request not found: ${request.id}`,
-        },
-        { status: 404 },
-      )
-    }
-  }, events)
-  let data!: ReturnType<typeof useData>
-
-  function Probe() {
-    data = useData()
-    return <box />
-  }
-
-  const app = await testRender(() => (
-    <TestTuiContexts>
-      <ClientProvider api={createApi(calls.fetch)}>
-        <ProjectProvider>
-          <DataProvider>
-            <Probe />
-          </DataProvider>
-        </ProjectProvider>
-      </ClientProvider>
-    </TestTuiContexts>
-  ))
-
-  try {
-    emitEvent(events, {
-      id: "evt_permission_asked_stale",
-      created: 0,
-      type: "permission.asked",
-      data: request,
-    })
-    await wait(() => data.session.permission.list(request.sessionID)?.length === 1)
-
-    await data.session.permission.reply({
-      sessionID: request.sessionID,
-      requestID: request.id,
-      reply: "once",
-    })
-
-    expect(replies).toBe(1)
-    expect(data.session.permission.list(request.sessionID)).toEqual([])
-  } finally {
-    app.renderer.destroy()
-  }
-})
-
 test("adds, dismisses, and refreshes form requests", async () => {
   const events = createEventStream()
   const calls = createFetch((url) => {

packages/www/content/docs/(Configure)/agents.mdx

@@ -46,9 +46,9 @@ An agent's `mode` controls where it can run:
 
 | Mode | Behavior |
 | --- | --- |
-| `primary` | Can be selected as the main agent for a session. It cannot be launched as a subagent. This is the default for a custom agent when `mode` is omitted. |
+| `primary` | Can be selected as the main agent for a session. It cannot be launched as a subagent. |
 | `subagent` | Can run in a child session through the `subagent` tool, but cannot be selected as the main agent. |
-| `all` | Can be used either way. |
+| `all` | Can be used either way. This is the default for a custom agent when `mode` is omitted. |
 
 In the TUI, press <kbd>Tab</kbd> and <kbd>Shift</kbd>+<kbd>Tab</kbd> to cycle
 through visible primary and `all` agents, or use `/agents` to choose one.

packages/www/content/docs/migrate-v1.mdx

@@ -419,8 +419,6 @@ The V1 provider filters do not have one-to-one native V2 config fields, but thei
 
 - `enabled_providers` becomes an internal deny-by-default provider policy followed by allows for the listed providers.
 - `disabled_providers` becomes internal deny policies for the listed providers.
-- `small_model` becomes the `model` selection for the built-in `title` agent. Native V2 configuration should use
-  `agents.title.model` instead.
 
 You may keep these fields in V1 syntax. OpenCode normalizes them without warning.
 
@@ -432,6 +430,7 @@ they are not mistaken for active configuration:
 - `logLevel`: use `OPENCODE_LOG_LEVEL` when starting OpenCode.
 - `server`: use the V2 service and explicit server options; the server API is an intentional breaking change.
 - `layout`: remove it; V1 already treated it as deprecated and always used stretch layout.
+- `small_model`: V2 selects models for internal maintenance agents without a separate top-level field.
 - Top-level `subagent_depth`: use `experimental.subagent_depth` instead.
 - `compaction.tail_turns` and `compaction.prune`: V2 uses `compaction.keep.tokens` and checkpoint-based compaction instead.
 - Agent `name` inside V1 JSON configuration.