Fix workspace context review findings

packages/fs/tool-fs/README.md

@@ -34,7 +34,7 @@ Field names are snake_case to match Claude Code and existing harness tool schema
 
 ## The tool is the executor; policy is an event gate
 
-The tools do **not** inject a policy service or inspect any cache. Each tool resolves the path via `ctx.fs.resolve(path, { cwd })` — passing the calling agent's session cwd (`exec.agent.session.header.cwd`) so a relative path resolves against the session's workspace, matching `dsh-tool-bash` (see [the per-session cwd RFC](../../../docs/rfc/implemented/architecture/2026-07-02-fs-per-session-cwd.md)) — then:
+The tools do **not** inject a policy service or inspect any cache. Each tool resolves the path via `ctx.fs.resolve(path, { cwd, signal })` — passing the calling agent's session cwd (`exec.agent.session.header.cwd`) so a relative path resolves against the session's workspace, matching `dsh-tool-bash`, and forwarding tool cancellation through resolution (see [the per-session cwd RFC](../../../docs/rfc/implemented/architecture/2026-07-02-fs-per-session-cwd.md)) — then:
 
 - **read** — one `ctx.fs.stat` (type + size routing + version), then `readText`/`streamText`, then builds the line window, then emits `fs/observed` with a plain `ctx.emit`. (1 stat.)
 - **write** — `ctx.waterfall('fs/write-intent', target, exec, () => undefined)` for the optional guard, then `ctx.fs.writeText(target, content, intent)`, then `fs/observed`. (0 stat.)

packages/fs/tool-fs/src/edit.ts

@@ -83,7 +83,10 @@ export function applyEditTool(ctx: Context): void {
     async execute(args, exec): Promise<{ content: ContentBlock[]; meta?: FsDiffMeta }> {
       const input = parseEditArgs(args)
       const cwd = sessionCwd(exec)
-      const target = await ctx.fs.resolve(input.filePath, cwd !== undefined ? { cwd } : undefined)
+      const target = await ctx.fs.resolve(input.filePath, {
+        ...cwd !== undefined ? { cwd } : {},
+        ...exec.signal !== undefined ? { signal: exec.signal } : {},
+      })
       // Single-slot decision: the policy plugin returns { version: vObserved } or
       // throws FS_NOT_OBSERVED; the bare default is undefined (unconditional edit).
       // No stat — the bare default never manufactures a version basis.

packages/fs/tool-fs/src/read.ts

@@ -95,7 +95,10 @@ export function applyReadTool(ctx: Context, caps: ReadToolCaps): void {
     async execute(args, exec): Promise<ContentBlock[]> {
       const input = parseReadArgs(args, caps.limit)
       const cwd = sessionCwd(exec)
-      const target = await ctx.fs.resolve(input.filePath, cwd !== undefined ? { cwd } : undefined)
+      const target = await ctx.fs.resolve(input.filePath, {
+        ...cwd !== undefined ? { cwd } : {},
+        ...exec.signal !== undefined ? { signal: exec.signal } : {},
+      })
 
       // One stat: type check + size routing + the version recorded as observed.
       // A writer racing between this stat and the read can at worst make a LATER

packages/fs/tool-fs/src/write.ts

@@ -68,7 +68,10 @@ export function applyWriteTool(ctx: Context): void {
     async execute(args, exec): Promise<{ content: ContentBlock[]; meta?: FsDiffMeta }> {
       const input = parseWriteArgs(args)
       const cwd = sessionCwd(exec)
-      const target = await ctx.fs.resolve(input.filePath, cwd !== undefined ? { cwd } : undefined)
+      const target = await ctx.fs.resolve(input.filePath, {
+        ...cwd !== undefined ? { cwd } : {},
+        ...exec.signal !== undefined ? { signal: exec.signal } : {},
+      })
       // Single-slot decision: the policy plugin produces createIfAbsent/
       // replaceIfVersion; the bare default is undefined (unconditional). No stat.
       const intent = await ctx.waterfall('fs/write-intent', target, exec, () => undefined)