fix(snapshot): register filesystem tools through explicit overlay

AGENTS.md

@@ -84,7 +84,7 @@ pnpm exec vitest run --config vitest.e2e.config.ts packages/ui/stdio-agent/tests
 
 ## Secrets / .env
 
-Real-API tests and demos read `DEEPSEEK_API_KEY` and optional `DEEPSEEK_BASE_URL` from the environment or a gitignored root `.env` loaded by `process.loadEnvFile()`. cordis.yml uses `!!js` (never `!js`) for env vars. Never commit credentials. CI e2e self-skips without a key; [docs/testing.md](docs/testing.md) owns the with-key policy.
+Real-API tests and demos read `DEEPSEEK_API_KEY`, optional `DEEPSEEK_BASE_URL`, and root `.env`. cordis.yml allows `!!js` (never `!js`) only under plugin `config`; Loader metadata is static, so conditional composition uses overlays ([primer](docs/cordis-primer.md#loader-configuration)). Never commit credentials. CI e2e skips without a key; [testing.md](docs/testing.md) owns key policy.
 
 ## Conventions
 

docs/cordis-primer.md

@@ -31,6 +31,10 @@ Cooperative listeners usually mutate a shared request or decision object and the
 
 For single-decision events, short-circuiting is the design. A policy listener can return without `next()` when it owns the decision, while a listener that only annotates or observes must delegate.
 
+## Loader Configuration
+
+`@cordisjs/plugin-include` parses `!!js` into expression nodes, but the Loader interpolates only an entry's `config` before mounting the plugin. Entry metadata (`id`, `name`, `group`, `disabled`, `inject`, `intercept`, and `isolate`) remains literal; `disabled: !!js ...` is therefore a truthy object that always disables the entry. Use explicit config overlays when environment selection changes which plugins are mounted.
+
 ## Practical Rules
 
 Encapsulate behavior into plugins: a tool pipeline event belongs to `ctx.tools`, model streaming belongs to `ctx.llm`, and live agent coordination belongs to `ctx.agents`. Prefer events for interception and policy; prefer service methods for direct capability calls.

docs/postmortem/0002-js-expression-disabled-filesystem-tools.md

@@ -0,0 +1,45 @@
+# Post-mortem 0002: Filesystem snapshot tools were permanently disabled
+
+Status: resolved
+
+## Executive summary
+
+The ACP example attempted to enable filesystem plugins conditionally with `disabled: !!js ...`, but Cordis evaluates JavaScript expressions only inside plugin `config`. The raw expression object was truthy, so the filesystem stack was always disabled. Snapshot refresh then accepted `UNKNOWN_TOOL` results as new goldens. The fix uses an explicit filesystem overlay and adds static-config and snapshot-result guards.
+
+## Summary
+
+The default ACP composition is intentionally bash-only because its sandbox cannot confine in-process filesystem providers. Filesystem snapshot scenarios still need `read`, `write`, and `edit`, so their plugins were placed in the default `cordis.yml` with a `disabled` expression intended to enable them only for full-access launches and snapshots.
+
+Cordis Include parsed each `!!js` scalar into an expression object. The Loader recursively interpolated the plugin's `config`, but consumed entry metadata such as `disabled` directly. Every filesystem entry therefore saw a truthy object and remained disabled in every mode.
+
+## Impact
+
+Seven filesystem scenarios and the mixed workspace-edit scenario called tools that were absent from the registry. Their structured session logs carried `ToolNotFoundError` with code `UNKNOWN_TOOL`, while stdout rendered generic failed tool cards. The snapshot suite passed because both surfaces matched the refreshed fixtures; it proved deterministic replay of the regression rather than successful filesystem behavior.
+
+The live confined default did not gain unintended filesystem access. A naive interpolation fix would have created that risk: permission presets update bash sandbox and approval state at runtime, but cannot mount, unmount, or confine the filesystem stack.
+
+## Timeline
+
+- PR #261 consolidated ACP compositions and refreshed the filesystem snapshots while introducing conditional filesystem entries.
+- All unit, coverage, snapshot, documentation, build, and hygiene checks passed.
+- Review of the refreshed filesystem goldens found generic failed cards and structured `UNKNOWN_TOOL` results.
+- A real Loader boot confirmed that every `disabled` value remained an expression object and every filesystem fiber was absent.
+
+## Root cause
+
+The implementation assumed `!!js` applied to an entire Loader entry. Its actual boundary is narrower: `Entry._resolveConfig()` interpolates only `entry.options.config`; `Entry.disabled` tests `entry.options.disabled` without interpolation. The YAML tag was syntactically valid, so loading produced no diagnostic.
+
+The snapshot framework treated any deterministic transcript as valid behavior. Header pins verified the composed tool schemas, but the filesystem scenarios shared a pin from the default composition and therefore did not independently prove that their required tools were registered. Refresh rewrote the expected stdout and session logs before any semantic assertion rejected missing tools.
+
+## Guardrails added
+
+- Filesystem scenarios boot `fs.cordis.yml`, an explicit fixed full-access overlay with a paired replay config and its own request-header class.
+- [`AGENTS.md`](../../AGENTS.md) and the [Cordis primer](../cordis-primer.md#loader-configuration) state that `!!js` is valid only under plugin `config` and conditional composition uses overlays.
+- `verify-cordis-config` parses repository Cordis YAML and rejects expression nodes in Loader entry metadata, including include patches and inserted entries.
+- `dsh-acp-snapshot` rejects structured `UNKNOWN_TOOL` results in fresh runs and committed session fixtures before they can become accepted goldens.
+
+## Lessons
+
+- A syntactically accepted configuration value is not necessarily evaluated at that location; document and verify interpolation boundaries.
+- A snapshot refresh is fixture production, not correctness review. Semantic impossibilities such as a missing registered tool need assertions independent of the golden.
+- Permission controls must describe only the capabilities they actually govern. Composition-time filesystem access cannot follow a runtime bash-only preset safely.

docs/postmortem/README.md

@@ -11,3 +11,4 @@ Every post-mortem opens with an **Executive summary**: one short paragraph a bus
 | # | Title |
 |---|---|
 | [0001](0001-acp-default-export-drops-inject.md) | ACP server crashed on connect: `export default` dropped the plugin's `inject` |
+| [0002](0002-js-expression-disabled-filesystem-tools.md) | Filesystem snapshot tools were permanently disabled by a literal `!!js` object |

examples/acp-agent/README.md

@@ -7,7 +7,7 @@ pnpm run demo:acp          # needs DEEPSEEK_API_KEY (repo-root .env or env)
 pnpm run demo:code-mode acp   # the same server in Code Mode: one wire tool, run_code
 ```
 
-The leaf config loads the ACP app, DeepSeek adapter, sandboxed bash, approval and permission services, model-facing tools, and repeat guard. The app bundles the agent spine, JSONL persistence, and bridge, creates agents on `session/new`, and keeps stdout logger-free. [`code-mode.cordis.yml`](code-mode.cordis.yml) overlays the same tree with `run_code` and its generated TypeScript SDK; see [Code Mode](../../packages/core/tools/README.md#code-mode).
+The leaf config loads the ACP app, DeepSeek adapter, sandboxed bash, approval and permission services, model-facing tools, and repeat guard. The app bundles the agent spine, JSONL persistence, and bridge, creates agents on `session/new`, and keeps stdout logger-free. [`fs.cordis.yml`](fs.cordis.yml) adds the unconfined in-process filesystem stack for its dedicated scenarios; [`code-mode.cordis.yml`](code-mode.cordis.yml) adds `run_code` and its generated TypeScript SDK. See [Code Mode](../../packages/core/tools/README.md#code-mode).
 
 ## stdout is the protocol
 
@@ -39,11 +39,11 @@ This example hosts the ACP snapshot suite. `dsh-llm-replay` reconstructs model s
 
 The default tree composes [`@deepseek-ai/dsh-sandbox-local`](../../packages/sandbox/sandbox-local/), [`@deepseek-ai/dsh-bash-sandbox`](../../packages/bash/bash-sandbox/), [`@deepseek-ai/dsh-user-approval`](../../packages/ui/user-approval/), and [`@deepseek-ai/dsh-permission`](../../packages/ui/permission/). Bash starts in `workspace-write`; a denied operation returns a structured marker, and a retry with `sandbox_permissions` plus `justification` becomes a one-shot `session/request_permission` prompt in the editor. "Allow once" runs exactly that retry under the wider mode ([sandbox RFC § Escalation](../../docs/rfc/implemented/feature/2026-07-06-sandbox.md)).
 
-- **One session config option is live**: a capable client shows one `Permissions` select. `workspace-write` means workspace-confined bash plus `ask`; `danger-full-access` means unconfined file access plus `never`. Switching writes one `permission/preset` event through to the sandbox-mode and approval-policy events, and `session/load` reports the resumed value.
+- **One session config option is live**: a capable client shows one `Permissions` select. `workspace-write` means workspace-confined bash plus `ask`; `danger-full-access` means unconfined bash plus `never`. Switching writes one `permission/preset` event through to the sandbox-mode and approval-policy events, and `session/load` reports the resumed value.
 - **Every approval is one-shot**: the choices are `Allow once` and `Reject`; a dismissal, rejection, missing editor, or unavailable runner fails closed.
 - **The boundary is bash-only and config-fixed today**: in-process filesystem tools are omitted from the confined live default, while the sandbox workspace root remains the server's launch directory.
 
-`tests/escalation.e2e.ts` boots this default tree keyless, drives the permission select, and—with a key and usable runner—proves both approval outcomes against the filesystem. The snapshot suite uses the same tree: snapshot mode starts at `danger-full-access` so established fixtures remain runner-independent, while the permission-switching and escalation inputs explicitly select `workspace-write` before exercising that policy path. No fixture pins a real denial because kernel error text is backend-specific; real confinement remains covered by the sandbox packages' kernel e2e suites.
+`tests/escalation.e2e.ts` boots this default tree keyless, drives the permission select, and—with a key and usable runner—proves both approval outcomes against the filesystem. Most snapshots use that tree and start at `danger-full-access` so bash fixtures remain runner-independent; scenarios that call `read`, `write`, or `edit` use the fixed full-access fs overlay and a separate request-header pin. The permission-switching and escalation inputs select `workspace-write` before exercising the bash policy path. No fixture pins a real denial because kernel error text is backend-specific; real confinement remains covered by the sandbox packages' kernel e2e suites.
 
 ## MVP limitations
 

examples/acp-agent/composition.md

@@ -45,12 +45,6 @@ flowchart LR
   cfg --> plugin_acp_tool_todo
   plugin_acp_repeat_tool_guard["repeat-tool-guard<br/>@deepseek-ai/dsh-repeat-tool-guard"]
   cfg --> plugin_acp_repeat_tool_guard
-  plugin_acp_fs_local["fs-local<br/>@deepseek-ai/dsh-fs-local"]
-  cfg --> plugin_acp_fs_local
-  plugin_acp_fs_policy["fs-policy<br/>@deepseek-ai/dsh-fs-policy"]
-  cfg --> plugin_acp_fs_policy
-  plugin_acp_tool_fs["tool-fs<br/>@deepseek-ai/dsh-tool-fs"]
-  cfg --> plugin_acp_tool_fs
   plugin_acp_hooks_claude["hooks-claude<br/>@deepseek-ai/dsh-hooks-claude"]
   cfg --> plugin_acp_hooks_claude
   plugin_acp_hooks_codex["hooks-codex<br/>@deepseek-ai/dsh-hooks-codex"]
@@ -74,9 +68,6 @@ flowchart LR
 | `tool-workflow` | `@deepseek-ai/dsh-tool-workflow` |
 | `tool-todo` | `@deepseek-ai/dsh-tool-todo` |
 | `repeat-tool-guard` | `@deepseek-ai/dsh-repeat-tool-guard` |
-| `fs-local` | `@deepseek-ai/dsh-fs-local` |
-| `fs-policy` | `@deepseek-ai/dsh-fs-policy` |
-| `tool-fs` | `@deepseek-ai/dsh-tool-fs` |
 | `hooks-claude` | `@deepseek-ai/dsh-hooks-claude` |
 | `hooks-codex` | `@deepseek-ai/dsh-hooks-codex` |
 

examples/acp-agent/cordis.yml

@@ -95,23 +95,6 @@
 - id: repeat-tool-guard
   name: '@deepseek-ai/dsh-repeat-tool-guard'
 
-# Filesystem tools do not ride the bash sandbox, so the confined default omits
-# them. Snapshots and explicit danger-full-access launches enable the local
-# provider, policy, and model-facing tools together.
-- id: fs-local
-  name: '@deepseek-ai/dsh-fs-local'
-  disabled: !!js "(process.env.DSH_PERMISSION_MODE ?? (process.env.DSH_SNAPSHOT === undefined ? 'workspace-write' : 'danger-full-access')) !== 'danger-full-access'"
-  config:
-    cwd: !!js process.cwd()
-
-- id: fs-policy
-  name: '@deepseek-ai/dsh-fs-policy'
-  disabled: !!js "(process.env.DSH_PERMISSION_MODE ?? (process.env.DSH_SNAPSHOT === undefined ? 'workspace-write' : 'danger-full-access')) !== 'danger-full-access'"
-
-- id: tool-fs
-  name: '@deepseek-ai/dsh-tool-fs'
-  disabled: !!js "(process.env.DSH_PERMISSION_MODE ?? (process.env.DSH_SNAPSHOT === undefined ? 'workspace-write' : 'danger-full-access')) !== 'danger-full-access'"
-
 # `configPath` is read once at load and resolves from the server launch cwd, not
 # `session/new.cwd`; one `hooks.json` therefore applies to every session and a
 # project-local file is not discovered. Missing config registers nothing. Hook

examples/acp-agent/fs.cordis.snapshot.yml

@@ -0,0 +1,21 @@
+# Keyless filesystem snapshots apply the filesystem and replay overlays directly
+# because include patches cannot target entries behind a nested include.
+- id: base
+  name: '@cordisjs/plugin-include'
+  config:
+    path: ./cordis.yml
+    patches:
+      - id: llm-deepseek
+        name: '@deepseek-ai/dsh-llm-deepseek'
+        disabled: true
+      - insert:
+          - id: fs-local
+            name: '@deepseek-ai/dsh-fs-local'
+            config:
+              cwd: !!js process.cwd()
+          - id: fs-policy
+            name: '@deepseek-ai/dsh-fs-policy'
+          - id: tool-fs
+            name: '@deepseek-ai/dsh-tool-fs'
+          - id: llm-replay
+            name: '@deepseek-ai/dsh-llm-replay'

examples/acp-agent/fs.cordis.yml

@@ -0,0 +1,17 @@
+# Filesystem snapshots need the in-process local provider, policy gate, and
+# model-facing tools. This explicit overlay is always full-access: the session
+# permission preset controls bash only and cannot confine or unmount these plugins.
+- id: base
+  name: '@cordisjs/plugin-include'
+  config:
+    path: ./cordis.yml
+    patches:
+      - insert:
+          - id: fs-local
+            name: '@deepseek-ai/dsh-fs-local'
+            config:
+              cwd: !!js process.cwd()
+          - id: fs-policy
+            name: '@deepseek-ai/dsh-fs-policy'
+          - id: tool-fs
+            name: '@deepseek-ai/dsh-tool-fs'

examples/acp-agent/tests/acp.snapshot.ts

@@ -27,6 +27,7 @@ const AGENT = {
 const CODE_MODE_CONFIG = fileURLToPath(new URL('../code-mode.cordis.yml', import.meta.url))
 const BOTH_MODE_CONFIG = fileURLToPath(new URL('../both-mode.cordis.yml', import.meta.url))
 const ADVANCED_CONFIG = fileURLToPath(new URL('../advanced.cordis.yml', import.meta.url))
+const FS_CONFIG = fileURLToPath(new URL('../fs.cordis.yml', import.meta.url))
 
 function snapshotModeFromEnv(value: string | undefined): SnapshotSuiteOptions['mode'] {
   switch (value) {
@@ -53,13 +54,13 @@ const SCENARIOS: Scenario[] = [
   { name: 'fs-terminal-card', hasModelTurn: true, recorded: true },
   { name: 'todo-plan', hasModelTurn: true, recorded: true },
   { name: 'skill-load', hasModelTurn: true, recorded: false, pinsHeader: true, headerClass: 'skill' },
-  { name: 'workspace-edit', hasModelTurn: true, recorded: true },
-  { name: 'fs-read', hasModelTurn: true, recorded: true },
-  { name: 'fs-write', hasModelTurn: true, recorded: true },
-  { name: 'fs-edit', hasModelTurn: true, recorded: true },
-  { name: 'fs-write-overwrite', hasModelTurn: true, recorded: true },
-  { name: 'fs-read-window', hasModelTurn: true, recorded: true },
-  { name: 'fs-policy-reject', hasModelTurn: true, recorded: true },
+  { name: 'workspace-edit', hasModelTurn: true, recorded: true, pinsHeader: true, headerClass: 'fs', configPath: FS_CONFIG },
+  { name: 'fs-read', hasModelTurn: true, recorded: true, headerClass: 'fs', configPath: FS_CONFIG },
+  { name: 'fs-write', hasModelTurn: true, recorded: true, headerClass: 'fs', configPath: FS_CONFIG },
+  { name: 'fs-edit', hasModelTurn: true, recorded: true, headerClass: 'fs', configPath: FS_CONFIG },
+  { name: 'fs-write-overwrite', hasModelTurn: true, recorded: true, headerClass: 'fs', configPath: FS_CONFIG },
+  { name: 'fs-read-window', hasModelTurn: true, recorded: true, headerClass: 'fs', configPath: FS_CONFIG },
+  { name: 'fs-policy-reject', hasModelTurn: true, recorded: true, headerClass: 'fs', configPath: FS_CONFIG },
   { name: 'multi-turn', hasModelTurn: true, recorded: true },
   { name: 'error-finish', hasModelTurn: true, recorded: false, overridden: true },
   // Keyless, authored (like error-finish/cancel): deterministically forcing a

examples/acp-agent/tests/snapshots/fs-edit/session.jsonl

@@ -69,7 +69,7 @@
 {"type":"assistant/chunk","seq":67,"time":1783352086057,"data":{"turn":1,"step":1,"chunk":{"type":"finish","reason":{"kind":"tool-calls"}}}}
 {"type":"assistant/message","seq":68,"time":1783352086059,"data":{"turn":1,"step":1,"content":[{"type":"reasoning","text":"The user wants me to:\n1. Read config.txt in the current directory\n2. Use the edit tool to replace DEBUG with RELEASE\n3. Reply with exactly \"DONE\"\n\nLet me start by reading the file."},{"type":"tool-call","id":"call_00_S6krdIDHoSCGWv7WnXX97617","name":"read","arguments":"{\"file_path\": \"config.txt\"}"}],"usage":{"inputTokens":2900,"outputTokens":91,"cacheReadTokens":0,"reasoningTokens":46}},"sourceEventSeqs":[4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67],"surfaceOp":"append"}
 {"type":"tool/call","seq":69,"time":1783352086059,"data":{"turn":1,"step":1,"callId":"call_00_S6krdIDHoSCGWv7WnXX97617","name":"read","arguments":"{\"file_path\": \"config.txt\"}"}}
-{"type":"tool/result","seq":70,"time":1783352086065,"data":{"turn":1,"step":1,"callId":"call_00_S6krdIDHoSCGWv7WnXX97617","content":[{"type":"text","text":"Error: unknown tool \"read\""}],"isError":true,"error":{"name":"ToolNotFoundError","code":"UNKNOWN_TOOL"}},"sourceEventSeqs":[69],"surfaceOp":"append"}
+{"type":"tool/result","seq":70,"time":1783352086065,"data":{"turn":1,"step":1,"callId":"call_00_S6krdIDHoSCGWv7WnXX97617","content":[{"type":"text","text":"<path>/tmp/acp-snap-cwd-0BxHdV/config.txt</path>\n<type>file</type>\n<content>\n1: mode=DEBUG\n2: level=info\n\n(End of file - total 2 lines)\n</content>"}],"isError":false},"sourceEventSeqs":[69],"surfaceOp":"append"}
 {"type":"step/end","seq":71,"time":1783352086065,"data":{"turn":1,"step":1}}
 {"type":"step/start","seq":72,"time":1783352086066,"data":{"turn":1,"step":2}}
 {"type":"assistant/chunk","seq":73,"time":1783352086901,"data":{"turn":1,"step":2,"chunk":{"type":"block-start","index":0,"blockType":"reasoning"}}}
@@ -129,7 +129,7 @@
 {"type":"assistant/chunk","seq":127,"time":1783352087469,"data":{"turn":1,"step":2,"chunk":{"type":"finish","reason":{"kind":"tool-calls"}}}}
 {"type":"assistant/message","seq":128,"time":1783352087469,"data":{"turn":1,"step":2,"content":[{"type":"reasoning","text":"Now I need to replace \"DEBUG\" with \"RELEASE\" using the edit tool."},{"type":"tool-call","id":"call_00_vOytneZ0XpsLslEEJAxR6398","name":"edit","arguments":"{\"file_path\": \"config.txt\", \"old_string\": \"DEBUG\", \"new_string\": \"RELEASE\"}"}],"usage":{"inputTokens":241,"outputTokens":98,"cacheReadTokens":2816,"reasoningTokens":18}},"sourceEventSeqs":[73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127],"surfaceOp":"append"}
 {"type":"tool/call","seq":129,"time":1783352087469,"data":{"turn":1,"step":2,"callId":"call_00_vOytneZ0XpsLslEEJAxR6398","name":"edit","arguments":"{\"file_path\": \"config.txt\", \"old_string\": \"DEBUG\", \"new_string\": \"RELEASE\"}"}}
-{"type":"tool/result","seq":130,"time":1783352087476,"data":{"turn":1,"step":2,"callId":"call_00_vOytneZ0XpsLslEEJAxR6398","content":[{"type":"text","text":"Error: unknown tool \"edit\""}],"isError":true,"error":{"name":"ToolNotFoundError","code":"UNKNOWN_TOOL"}},"sourceEventSeqs":[129],"surfaceOp":"append"}
+{"type":"tool/result","seq":130,"time":1783352087476,"data":{"turn":1,"step":2,"callId":"call_00_vOytneZ0XpsLslEEJAxR6398","content":[{"type":"text","text":"The file /tmp/acp-snap-cwd-0BxHdV/config.txt has been updated successfully."}],"isError":false,"meta":{"diffs":[{"path":"config.txt","oldText":"mode=DEBUG\nlevel=info","newText":"mode=RELEASE\nlevel=info"}]}},"sourceEventSeqs":[129],"surfaceOp":"append"}
 {"type":"step/end","seq":131,"time":1783352087477,"data":{"turn":1,"step":2}}
 {"type":"step/start","seq":132,"time":1783352087477,"data":{"turn":1,"step":3}}
 {"type":"assistant/chunk","seq":133,"time":1783352088286,"data":{"turn":1,"step":3,"chunk":{"type":"block-start","index":0,"blockType":"reasoning"}}}

examples/acp-agent/tests/snapshots/fs-edit/stdout.golden.jsonl

@@ -46,8 +46,8 @@
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" the"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" file"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"."}}}}
-{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"call_00_S6krdIDHoSCGWv7WnXX97617","title":"read","kind":"other","status":"in_progress","rawInput":{"file_path":"config.txt"}}}}
-{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_00_S6krdIDHoSCGWv7WnXX97617","status":"failed","content":[{"type":"content","content":{"type":"text","text":"Error: unknown tool \"read\""}}]}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"call_00_S6krdIDHoSCGWv7WnXX97617","title":"Read config.txt","kind":"read","status":"in_progress","locations":[{"path":"config.txt","line":1}]}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_00_S6krdIDHoSCGWv7WnXX97617","status":"completed","content":[{"type":"content","content":{"type":"text","text":"<path>{{cwd}}/config.txt</path>\n<type>file</type>\n<content>\n1: mode=DEBUG\n2: level=info\n\n(End of file - total 2 lines)\n</content>"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"Now"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" I"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" need"}}}}
@@ -66,8 +66,8 @@
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" edit"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" tool"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"."}}}}
-{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"call_00_vOytneZ0XpsLslEEJAxR6398","title":"edit","kind":"other","status":"in_progress","rawInput":{"file_path":"config.txt","old_string":"DEBUG","new_string":"RELEASE"}}}}
-{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_00_vOytneZ0XpsLslEEJAxR6398","status":"failed","content":[{"type":"content","content":{"type":"text","text":"Error: unknown tool \"edit\""}}]}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"call_00_vOytneZ0XpsLslEEJAxR6398","title":"Edit config.txt","kind":"edit","status":"in_progress","locations":[{"path":"config.txt"}],"content":[{"type":"diff","path":"config.txt","oldText":"DEBUG","newText":"RELEASE"}]}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_00_vOytneZ0XpsLslEEJAxR6398","status":"completed","content":[{"type":"diff","path":"config.txt","oldText":"mode=DEBUG\nlevel=info","newText":"mode=RELEASE\nlevel=info"}],"title":"Edit config.txt"}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"Done"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"."}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" The"}}}}

examples/acp-agent/tests/snapshots/fs-policy-reject/session.jsonl

@@ -77,7 +77,7 @@
 {"type":"assistant/chunk","seq":75,"time":1783611703969,"data":{"turn":1,"step":1,"chunk":{"type":"finish","reason":{"kind":"tool-calls"}}}}
 {"type":"assistant/message","seq":76,"time":1783611703972,"data":{"turn":1,"step":1,"content":[{"type":"reasoning","text":"The user wants me to use the edit tool to replace \"blue\" with \"green\" in settings.txt without reading the file first, and then reply with just \"DONE\"."},{"type":"tool-call","id":"call_00_x0zlnXl5JOxLrAYL9y7P0119","name":"edit","arguments":"{\"file_path\": \"settings.txt\", \"old_string\": \"blue\", \"new_string\": \"green\"}"}],"usage":{"inputTokens":3132,"outputTokens":115,"cacheReadTokens":0,"reasoningTokens":36}},"sourceEventSeqs":[4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75],"surfaceOp":"append"}
 {"type":"tool/call","seq":77,"time":1783611703972,"data":{"turn":1,"step":1,"callId":"call_00_x0zlnXl5JOxLrAYL9y7P0119","name":"edit","arguments":"{\"file_path\": \"settings.txt\", \"old_string\": \"blue\", \"new_string\": \"green\"}"}}
-{"type":"tool/result","seq":78,"time":1783611703978,"data":{"turn":1,"step":1,"callId":"call_00_x0zlnXl5JOxLrAYL9y7P0119","content":[{"type":"text","text":"Error: unknown tool \"edit\""}],"isError":true,"error":{"name":"ToolNotFoundError","code":"UNKNOWN_TOOL"}},"sourceEventSeqs":[77],"surfaceOp":"append"}
+{"type":"tool/result","seq":78,"time":1783611703978,"data":{"turn":1,"step":1,"callId":"call_00_x0zlnXl5JOxLrAYL9y7P0119","content":[{"type":"text","text":"Error: edit requires reading \"/var/folders/2c/psb0_fmx7hbgz558xjt_f0l00000gn/T/acp-snap-cwd-QzoqnB/settings.txt\" first"}],"isError":true,"error":{"name":"FsError","code":"FS_NOT_OBSERVED"}},"sourceEventSeqs":[77],"surfaceOp":"append"}
 {"type":"step/end","seq":79,"time":1783611703978,"data":{"turn":1,"step":1}}
 {"type":"step/start","seq":80,"time":1783611703978,"data":{"turn":1,"step":2}}
 {"type":"assistant/chunk","seq":81,"time":1783611704825,"data":{"turn":1,"step":2,"chunk":{"type":"block-start","index":0,"blockType":"reasoning"}}}
@@ -144,7 +144,7 @@
 {"type":"assistant/chunk","seq":142,"time":1783611705572,"data":{"turn":1,"step":2,"chunk":{"type":"finish","reason":{"kind":"tool-calls"}}}}
 {"type":"assistant/message","seq":143,"time":1783611705573,"data":{"turn":1,"step":2,"content":[{"type":"reasoning","text":"The edit tool requires reading the file first. The user said \"Do not read the file first\" but the tool's own constraints require reading. I need to follow the tool requirements. Let me read the file first."},{"type":"tool-call","id":"call_00_tfr0gdIclW92oIEgi7NF0891","name":"read","arguments":"{\"file_path\": \"settings.txt\"}"}],"usage":{"inputTokens":235,"outputTokens":89,"cacheReadTokens":3072,"reasoningTokens":44}},"sourceEventSeqs":[81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,128,129,130,131,132,133,134,135,136,137,138,139,140,141,142],"surfaceOp":"append"}
 {"type":"tool/call","seq":144,"time":1783611705573,"data":{"turn":1,"step":2,"callId":"call_00_tfr0gdIclW92oIEgi7NF0891","name":"read","arguments":"{\"file_path\": \"settings.txt\"}"}}
-{"type":"tool/result","seq":145,"time":1783611705579,"data":{"turn":1,"step":2,"callId":"call_00_tfr0gdIclW92oIEgi7NF0891","content":[{"type":"text","text":"Error: unknown tool \"read\""}],"isError":true,"error":{"name":"ToolNotFoundError","code":"UNKNOWN_TOOL"}},"sourceEventSeqs":[144],"surfaceOp":"append"}
+{"type":"tool/result","seq":145,"time":1783611705579,"data":{"turn":1,"step":2,"callId":"call_00_tfr0gdIclW92oIEgi7NF0891","content":[{"type":"text","text":"<path>/var/folders/2c/psb0_fmx7hbgz558xjt_f0l00000gn/T/acp-snap-cwd-QzoqnB/settings.txt</path>\n<type>file</type>\n<content>\n1: color: blue\n\n(End of file - total 1 lines)\n</content>"}],"isError":false},"sourceEventSeqs":[144],"surfaceOp":"append"}
 {"type":"step/end","seq":146,"time":1783611705579,"data":{"turn":1,"step":2}}
 {"type":"step/start","seq":147,"time":1783611705579,"data":{"turn":1,"step":3}}
 {"type":"assistant/chunk","seq":148,"time":1783611706200,"data":{"turn":1,"step":3,"chunk":{"type":"block-start","index":0,"blockType":"reasoning"}}}
@@ -225,7 +225,7 @@
 {"type":"assistant/chunk","seq":223,"time":1783611707096,"data":{"turn":1,"step":3,"chunk":{"type":"finish","reason":{"kind":"tool-calls"}}}}
 {"type":"assistant/message","seq":224,"time":1783611707097,"data":{"turn":1,"step":3,"content":[{"type":"reasoning","text":"The file contains \"color: blue\". I need to replace \"blue\" with \"green\". The edit tool said it requires reading first — now I've read it, so the edit should work."},{"type":"tool-call","id":"call_00_GVknJu2tksKkP4lALCwh0926","name":"edit","arguments":"{\"file_path\": \"settings.txt\", \"old_string\": \"blue\", \"new_string\": \"green\"}"}],"usage":{"inputTokens":281,"outputTokens":119,"cacheReadTokens":3200,"reasoningTokens":40}},"sourceEventSeqs":[148,149,150,151,152,153,154,155,156,157,158,159,160,161,162,163,164,165,166,167,168,169,170,171,172,173,174,175,176,177,178,179,180,181,182,183,184,185,186,187,188,189,190,191,192,193,194,195,196,197,198,199,200,201,202,203,204,205,206,207,208,209,210,211,212,213,214,215,216,217,218,219,220,221,222,223],"surfaceOp":"append"}
 {"type":"tool/call","seq":225,"time":1783611707097,"data":{"turn":1,"step":3,"callId":"call_00_GVknJu2tksKkP4lALCwh0926","name":"edit","arguments":"{\"file_path\": \"settings.txt\", \"old_string\": \"blue\", \"new_string\": \"green\"}"}}
-{"type":"tool/result","seq":226,"time":1783611707114,"data":{"turn":1,"step":3,"callId":"call_00_GVknJu2tksKkP4lALCwh0926","content":[{"type":"text","text":"Error: unknown tool \"edit\""}],"isError":true,"error":{"name":"ToolNotFoundError","code":"UNKNOWN_TOOL"}},"sourceEventSeqs":[225],"surfaceOp":"append"}
+{"type":"tool/result","seq":226,"time":1783611707114,"data":{"turn":1,"step":3,"callId":"call_00_GVknJu2tksKkP4lALCwh0926","content":[{"type":"text","text":"The file /var/folders/2c/psb0_fmx7hbgz558xjt_f0l00000gn/T/acp-snap-cwd-QzoqnB/settings.txt has been updated successfully."}],"isError":false,"meta":{"diffs":[{"path":"settings.txt","oldText":"color: blue","newText":"color: green"}]}},"sourceEventSeqs":[225],"surfaceOp":"append"}
 {"type":"step/end","seq":227,"time":1783611707114,"data":{"turn":1,"step":3}}
 {"type":"step/start","seq":228,"time":1783611707114,"data":{"turn":1,"step":4}}
 {"type":"assistant/chunk","seq":229,"time":1783611707747,"data":{"turn":1,"step":4,"chunk":{"type":"block-start","index":0,"blockType":"reasoning"}}}

examples/acp-agent/tests/snapshots/fs-policy-reject/stdout.golden.jsonl

@@ -36,8 +36,8 @@
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"D"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"ONE"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"\"."}}}}
-{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"call_00_x0zlnXl5JOxLrAYL9y7P0119","title":"edit","kind":"other","status":"in_progress","rawInput":{"file_path":"settings.txt","old_string":"blue","new_string":"green"}}}}
-{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_00_x0zlnXl5JOxLrAYL9y7P0119","status":"failed","content":[{"type":"content","content":{"type":"text","text":"Error: unknown tool \"edit\""}}]}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"call_00_x0zlnXl5JOxLrAYL9y7P0119","title":"Edit settings.txt","kind":"edit","status":"in_progress","locations":[{"path":"settings.txt"}],"content":[{"type":"diff","path":"settings.txt","oldText":"blue","newText":"green"}]}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_00_x0zlnXl5JOxLrAYL9y7P0119","status":"failed","content":[{"type":"content","content":{"type":"text","text":"Error: edit requires reading \"{{cwd}}/settings.txt\" first"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"The"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" edit"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" tool"}}}}
@@ -82,8 +82,8 @@
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" file"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" first"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"."}}}}
-{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"call_00_tfr0gdIclW92oIEgi7NF0891","title":"read","kind":"other","status":"in_progress","rawInput":{"file_path":"settings.txt"}}}}
-{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_00_tfr0gdIclW92oIEgi7NF0891","status":"failed","content":[{"type":"content","content":{"type":"text","text":"Error: unknown tool \"read\""}}]}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"call_00_tfr0gdIclW92oIEgi7NF0891","title":"Read settings.txt","kind":"read","status":"in_progress","locations":[{"path":"settings.txt","line":1}]}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_00_tfr0gdIclW92oIEgi7NF0891","status":"completed","content":[{"type":"content","content":{"type":"text","text":"<path>{{cwd}}/settings.txt</path>\n<type>file</type>\n<content>\n1: color: blue\n\n(End of file - total 1 lines)\n</content>"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"The"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" file"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" contains"}}}}
@@ -124,8 +124,8 @@
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" should"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" work"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"."}}}}
-{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"call_00_GVknJu2tksKkP4lALCwh0926","title":"edit","kind":"other","status":"in_progress","rawInput":{"file_path":"settings.txt","old_string":"blue","new_string":"green"}}}}
-{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_00_GVknJu2tksKkP4lALCwh0926","status":"failed","content":[{"type":"content","content":{"type":"text","text":"Error: unknown tool \"edit\""}}]}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"call_00_GVknJu2tksKkP4lALCwh0926","title":"Edit settings.txt","kind":"edit","status":"in_progress","locations":[{"path":"settings.txt"}],"content":[{"type":"diff","path":"settings.txt","oldText":"blue","newText":"green"}]}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_00_GVknJu2tksKkP4lALCwh0926","status":"completed","content":[{"type":"diff","path":"settings.txt","oldText":"color: blue","newText":"color: green"}],"title":"Edit settings.txt"}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"The"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" replacement"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" was"}}}}

examples/acp-agent/tests/snapshots/fs-read-window/session.jsonl

@@ -91,7 +91,7 @@
 {"type":"assistant/chunk","seq":89,"time":1783352101346,"data":{"turn":1,"step":1,"chunk":{"type":"finish","reason":{"kind":"tool-calls"}}}}
 {"type":"assistant/message","seq":90,"time":1783352101348,"data":{"turn":1,"step":1,"content":[{"type":"reasoning","text":"The user wants me to use the read tool with offset 5 and limit 4 to read lines 5 through 8 of big.txt in the current directory. Then reply with exactly the single word DONE.\n\nLet me first check the current directory, then read the file."},{"type":"tool-call","id":"call_00_GIZwZS9a7vhWTFCIc7Z35497","name":"read","arguments":"{\"file_path\": \"big.txt\", \"offset\": 5, \"limit\": 4}"}],"usage":{"inputTokens":2894,"outputTokens":133,"cacheReadTokens":0,"reasoningTokens":56}},"sourceEventSeqs":[4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89],"surfaceOp":"append"}
 {"type":"tool/call","seq":91,"time":1783352101348,"data":{"turn":1,"step":1,"callId":"call_00_GIZwZS9a7vhWTFCIc7Z35497","name":"read","arguments":"{\"file_path\": \"big.txt\", \"offset\": 5, \"limit\": 4}"}}
-{"type":"tool/result","seq":92,"time":1783352101353,"data":{"turn":1,"step":1,"callId":"call_00_GIZwZS9a7vhWTFCIc7Z35497","content":[{"type":"text","text":"Error: unknown tool \"read\""}],"isError":true,"error":{"name":"ToolNotFoundError","code":"UNKNOWN_TOOL"}},"sourceEventSeqs":[91],"surfaceOp":"append"}
+{"type":"tool/result","seq":92,"time":1783352101353,"data":{"turn":1,"step":1,"callId":"call_00_GIZwZS9a7vhWTFCIc7Z35497","content":[{"type":"text","text":"<path>/tmp/acp-snap-cwd-N9HCkt/big.txt</path>\n<type>file</type>\n<content>\n5: line five\n6: line six\n7: line seven\n8: line eight\n\n(Showing lines 5-8 of 10. Use offset=9 to continue.)\n</content>"}],"isError":false},"sourceEventSeqs":[91],"surfaceOp":"append"}
 {"type":"step/end","seq":93,"time":1783352101353,"data":{"turn":1,"step":1}}
 {"type":"step/start","seq":94,"time":1783352101354,"data":{"turn":1,"step":2}}
 {"type":"assistant/chunk","seq":95,"time":1783352102021,"data":{"turn":1,"step":2,"chunk":{"type":"block-start","index":0,"blockType":"reasoning"}}}

examples/acp-agent/tests/snapshots/fs-read-window/stdout.golden.jsonl

@@ -56,8 +56,8 @@
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" the"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" file"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"."}}}}
-{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"call_00_GIZwZS9a7vhWTFCIc7Z35497","title":"read","kind":"other","status":"in_progress","rawInput":{"file_path":"big.txt","offset":5,"limit":4}}}}
-{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_00_GIZwZS9a7vhWTFCIc7Z35497","status":"failed","content":[{"type":"content","content":{"type":"text","text":"Error: unknown tool \"read\""}}]}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"call_00_GIZwZS9a7vhWTFCIc7Z35497","title":"Read big.txt (5 - 8)","kind":"read","status":"in_progress","locations":[{"path":"big.txt","line":5}]}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_00_GIZwZS9a7vhWTFCIc7Z35497","status":"completed","content":[{"type":"content","content":{"type":"text","text":"<path>{{cwd}}/big.txt</path>\n<type>file</type>\n<content>\n5: line five\n6: line six\n7: line seven\n8: line eight\n\n(Showing lines 5-8 of 10. Use offset=9 to continue.)\n</content>"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"The"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" read"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" tool"}}}}

examples/acp-agent/tests/snapshots/fs-read/session.jsonl

@@ -53,7 +53,7 @@
 {"type":"assistant/chunk","seq":51,"time":1783352073705,"data":{"turn":1,"step":1,"chunk":{"type":"finish","reason":{"kind":"tool-calls"}}}}
 {"type":"assistant/message","seq":52,"time":1783352073708,"data":{"turn":1,"step":1,"content":[{"type":"reasoning","text":"The user wants me to read the file greeting.txt using the read tool (not bash), then reply with exactly the single word \"DONE\"."},{"type":"tool-call","id":"call_00_hHPZCcivsIkXAGS9jTGy8417","name":"read","arguments":"{\"file_path\": \"greeting.txt\"}"}],"usage":{"inputTokens":2882,"outputTokens":75,"cacheReadTokens":0,"reasoningTokens":29}},"sourceEventSeqs":[4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51],"surfaceOp":"append"}
 {"type":"tool/call","seq":53,"time":1783352073709,"data":{"turn":1,"step":1,"callId":"call_00_hHPZCcivsIkXAGS9jTGy8417","name":"read","arguments":"{\"file_path\": \"greeting.txt\"}"}}
-{"type":"tool/result","seq":54,"time":1783352073717,"data":{"turn":1,"step":1,"callId":"call_00_hHPZCcivsIkXAGS9jTGy8417","content":[{"type":"text","text":"Error: unknown tool \"read\""}],"isError":true,"error":{"name":"ToolNotFoundError","code":"UNKNOWN_TOOL"}},"sourceEventSeqs":[53],"surfaceOp":"append"}
+{"type":"tool/result","seq":54,"time":1783352073717,"data":{"turn":1,"step":1,"callId":"call_00_hHPZCcivsIkXAGS9jTGy8417","content":[{"type":"text","text":"<path>/tmp/acp-snap-cwd-PEETkS/greeting.txt</path>\n<type>file</type>\n<content>\n1: hello\n\n(End of file - total 1 lines)\n</content>"}],"isError":false},"sourceEventSeqs":[53],"surfaceOp":"append"}
 {"type":"step/end","seq":55,"time":1783352073718,"data":{"turn":1,"step":1}}
 {"type":"step/start","seq":56,"time":1783352073719,"data":{"turn":1,"step":2}}
 {"type":"assistant/chunk","seq":57,"time":1783352074666,"data":{"turn":1,"step":2,"chunk":{"type":"block-start","index":0,"blockType":"reasoning"}}}

examples/acp-agent/tests/snapshots/fs-read/stdout.golden.jsonl

@@ -29,8 +29,8 @@
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"D"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"ONE"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"\"."}}}}
-{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"call_00_hHPZCcivsIkXAGS9jTGy8417","title":"read","kind":"other","status":"in_progress","rawInput":{"file_path":"greeting.txt"}}}}
-{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_00_hHPZCcivsIkXAGS9jTGy8417","status":"failed","content":[{"type":"content","content":{"type":"text","text":"Error: unknown tool \"read\""}}]}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"call_00_hHPZCcivsIkXAGS9jTGy8417","title":"Read greeting.txt","kind":"read","status":"in_progress","locations":[{"path":"greeting.txt","line":1}]}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_00_hHPZCcivsIkXAGS9jTGy8417","status":"completed","content":[{"type":"content","content":{"type":"text","text":"<path>{{cwd}}/greeting.txt</path>\n<type>file</type>\n<content>\n1: hello\n\n(End of file - total 1 lines)\n</content>"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"The"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" user"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" asked"}}}}

examples/acp-agent/tests/snapshots/fs-write-overwrite/session.jsonl

@@ -65,7 +65,7 @@
 {"type":"assistant/chunk","seq":63,"time":1783352093614,"data":{"turn":1,"step":1,"chunk":{"type":"finish","reason":{"kind":"tool-calls"}}}}
 {"type":"assistant/message","seq":64,"time":1783352093617,"data":{"turn":1,"step":1,"content":[{"type":"reasoning","text":"The user wants me to:\n1. Read data.txt using the read tool\n2. Replace its entire contents with exactly \"replaced\" using the write tool\n3. Reply with exactly \"DONE\""},{"type":"tool-call","id":"call_00_n4eRJuGoxNR07svgNtk82243","name":"read","arguments":"{\"file_path\": \"data.txt\"}"}],"usage":{"inputTokens":2899,"outputTokens":87,"cacheReadTokens":0,"reasoningTokens":42}},"sourceEventSeqs":[4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63],"surfaceOp":"append"}
 {"type":"tool/call","seq":65,"time":1783352093617,"data":{"turn":1,"step":1,"callId":"call_00_n4eRJuGoxNR07svgNtk82243","name":"read","arguments":"{\"file_path\": \"data.txt\"}"}}
-{"type":"tool/result","seq":66,"time":1783352093624,"data":{"turn":1,"step":1,"callId":"call_00_n4eRJuGoxNR07svgNtk82243","content":[{"type":"text","text":"Error: unknown tool \"read\""}],"isError":true,"error":{"name":"ToolNotFoundError","code":"UNKNOWN_TOOL"}},"sourceEventSeqs":[65],"surfaceOp":"append"}
+{"type":"tool/result","seq":66,"time":1783352093624,"data":{"turn":1,"step":1,"callId":"call_00_n4eRJuGoxNR07svgNtk82243","content":[{"type":"text","text":"<path>/tmp/acp-snap-cwd-hH2sGY/data.txt</path>\n<type>file</type>\n<content>\n1: original contents\n\n(End of file - total 1 lines)\n</content>"}],"isError":false},"sourceEventSeqs":[65],"surfaceOp":"append"}
 {"type":"step/end","seq":67,"time":1783352093624,"data":{"turn":1,"step":1}}
 {"type":"step/start","seq":68,"time":1783352093625,"data":{"turn":1,"step":2}}
 {"type":"assistant/chunk","seq":69,"time":1783352094455,"data":{"turn":1,"step":2,"chunk":{"type":"block-start","index":0,"blockType":"reasoning"}}}
@@ -114,7 +114,7 @@
 {"type":"assistant/chunk","seq":112,"time":1783352094988,"data":{"turn":1,"step":2,"chunk":{"type":"finish","reason":{"kind":"tool-calls"}}}}
 {"type":"assistant/message","seq":113,"time":1783352094988,"data":{"turn":1,"step":2,"content":[{"type":"reasoning","text":"The file contains \"original contents\". Now I'll replace it with \"replaced\"."},{"type":"tool-call","id":"call_00_N23EvXjDo4c8enyWpIUq4043","name":"write","arguments":"{\"file_path\": \"data.txt\", \"content\": \"replaced\"}"}],"usage":{"inputTokens":228,"outputTokens":79,"cacheReadTokens":2816,"reasoningTokens":17}},"sourceEventSeqs":[69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112],"surfaceOp":"append"}
 {"type":"tool/call","seq":114,"time":1783352094988,"data":{"turn":1,"step":2,"callId":"call_00_N23EvXjDo4c8enyWpIUq4043","name":"write","arguments":"{\"file_path\": \"data.txt\", \"content\": \"replaced\"}"}}
-{"type":"tool/result","seq":115,"time":1783352094995,"data":{"turn":1,"step":2,"callId":"call_00_N23EvXjDo4c8enyWpIUq4043","content":[{"type":"text","text":"Error: unknown tool \"write\""}],"isError":true,"error":{"name":"ToolNotFoundError","code":"UNKNOWN_TOOL"}},"sourceEventSeqs":[114],"surfaceOp":"append"}
+{"type":"tool/result","seq":115,"time":1783352094995,"data":{"turn":1,"step":2,"callId":"call_00_N23EvXjDo4c8enyWpIUq4043","content":[{"type":"text","text":"<path>/tmp/acp-snap-cwd-hH2sGY/data.txt</path>\n<type>file</type>\n<content>\nUpdated file\n</content>"}],"isError":false,"meta":{"diffs":[{"path":"data.txt","oldText":"original contents","newText":"replaced"}]}},"sourceEventSeqs":[114],"surfaceOp":"append"}
 {"type":"step/end","seq":116,"time":1783352094995,"data":{"turn":1,"step":2}}
 {"type":"step/start","seq":117,"time":1783352094995,"data":{"turn":1,"step":3}}
 {"type":"assistant/chunk","seq":118,"time":1783352096090,"data":{"turn":1,"step":3,"chunk":{"type":"block-start","index":0,"blockType":"reasoning"}}}

examples/acp-agent/tests/snapshots/fs-write-overwrite/stdout.golden.jsonl

@@ -42,8 +42,8 @@
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"D"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"ONE"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"\""}}}}
-{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"call_00_n4eRJuGoxNR07svgNtk82243","title":"read","kind":"other","status":"in_progress","rawInput":{"file_path":"data.txt"}}}}
-{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_00_n4eRJuGoxNR07svgNtk82243","status":"failed","content":[{"type":"content","content":{"type":"text","text":"Error: unknown tool \"read\""}}]}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"call_00_n4eRJuGoxNR07svgNtk82243","title":"Read data.txt","kind":"read","status":"in_progress","locations":[{"path":"data.txt","line":1}]}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_00_n4eRJuGoxNR07svgNtk82243","status":"completed","content":[{"type":"content","content":{"type":"text","text":"<path>{{cwd}}/data.txt</path>\n<type>file</type>\n<content>\n1: original contents\n\n(End of file - total 1 lines)\n</content>"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"The"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" file"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" contains"}}}}
@@ -61,8 +61,8 @@
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"re"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"placed"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"\"."}}}}
-{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"call_00_N23EvXjDo4c8enyWpIUq4043","title":"write","kind":"other","status":"in_progress","rawInput":{"file_path":"data.txt","content":"replaced"}}}}
-{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_00_N23EvXjDo4c8enyWpIUq4043","status":"failed","content":[{"type":"content","content":{"type":"text","text":"Error: unknown tool \"write\""}}]}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"call_00_N23EvXjDo4c8enyWpIUq4043","title":"Write data.txt","kind":"edit","status":"in_progress","locations":[{"path":"data.txt"}],"content":[{"type":"diff","path":"data.txt","oldText":null,"newText":"replaced"}]}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_00_N23EvXjDo4c8enyWpIUq4043","status":"completed","content":[{"type":"diff","path":"data.txt","oldText":"original contents","newText":"replaced"}],"title":"Write data.txt"}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"The"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" file"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" has"}}}}

examples/acp-agent/tests/snapshots/fs-write/session.jsonl

@@ -62,7 +62,7 @@
 {"type":"assistant/chunk","seq":60,"time":1783352079886,"data":{"turn":1,"step":1,"chunk":{"type":"finish","reason":{"kind":"tool-calls"}}}}
 {"type":"assistant/message","seq":61,"time":1783352079888,"data":{"turn":1,"step":1,"content":[{"type":"reasoning","text":"The user wants me to create a file named notes.txt with the content \"hello world\" using the write tool, then reply with \"DONE\"."},{"type":"tool-call","id":"call_00_APMUCJJm9lrTSlVbg6dB0185","name":"write","arguments":"{\"file_path\": \"notes.txt\", \"content\": \"hello world\"}"}],"usage":{"inputTokens":2891,"outputTokens":92,"cacheReadTokens":0,"reasoningTokens":30}},"sourceEventSeqs":[4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60],"surfaceOp":"append"}
 {"type":"tool/call","seq":62,"time":1783352079888,"data":{"turn":1,"step":1,"callId":"call_00_APMUCJJm9lrTSlVbg6dB0185","name":"write","arguments":"{\"file_path\": \"notes.txt\", \"content\": \"hello world\"}"}}
-{"type":"tool/result","seq":63,"time":1783352079897,"data":{"turn":1,"step":1,"callId":"call_00_APMUCJJm9lrTSlVbg6dB0185","content":[{"type":"text","text":"Error: unknown tool \"write\""}],"isError":true,"error":{"name":"ToolNotFoundError","code":"UNKNOWN_TOOL"}},"sourceEventSeqs":[62],"surfaceOp":"append"}
+{"type":"tool/result","seq":63,"time":1783352079897,"data":{"turn":1,"step":1,"callId":"call_00_APMUCJJm9lrTSlVbg6dB0185","content":[{"type":"text","text":"<path>/tmp/acp-snap-cwd-sNvn5N/notes.txt</path>\n<type>file</type>\n<content>\nCreated file\n</content>"}],"isError":false},"sourceEventSeqs":[62],"surfaceOp":"append"}
 {"type":"step/end","seq":64,"time":1783352079898,"data":{"turn":1,"step":1}}
 {"type":"step/start","seq":65,"time":1783352079899,"data":{"turn":1,"step":2}}
 {"type":"assistant/chunk","seq":66,"time":1783352080825,"data":{"turn":1,"step":2,"chunk":{"type":"block-start","index":0,"blockType":"reasoning"}}}

examples/acp-agent/tests/snapshots/fs-write/stdout.golden.jsonl

@@ -30,8 +30,8 @@
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"D"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"ONE"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"\"."}}}}
-{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"call_00_APMUCJJm9lrTSlVbg6dB0185","title":"write","kind":"other","status":"in_progress","rawInput":{"file_path":"notes.txt","content":"hello world"}}}}
-{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_00_APMUCJJm9lrTSlVbg6dB0185","status":"failed","content":[{"type":"content","content":{"type":"text","text":"Error: unknown tool \"write\""}}]}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"call_00_APMUCJJm9lrTSlVbg6dB0185","title":"Write notes.txt","kind":"edit","status":"in_progress","locations":[{"path":"notes.txt"}],"content":[{"type":"diff","path":"notes.txt","oldText":null,"newText":"hello world"}]}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_00_APMUCJJm9lrTSlVbg6dB0185","status":"completed","content":[{"type":"diff","path":"notes.txt","oldText":null,"newText":"hello world"}],"title":"Write notes.txt"}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"The"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" file"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" has"}}}}

examples/acp-agent/tests/snapshots/workspace-edit/stdout.golden.jsonl

@@ -55,8 +55,8 @@
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" its"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" contents"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"."}}}}
-{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"call_00_OjRFB4zvxu6UALDjytZD0978","title":"read","kind":"other","status":"in_progress","rawInput":{"file_path":"greeting.txt"}}}}
-{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_00_OjRFB4zvxu6UALDjytZD0978","status":"failed","content":[{"type":"content","content":{"type":"text","text":"Error: unknown tool \"read\""}}]}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"call_00_OjRFB4zvxu6UALDjytZD0978","title":"Read greeting.txt","kind":"read","status":"in_progress","locations":[{"path":"greeting.txt","line":1}]}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_00_OjRFB4zvxu6UALDjytZD0978","status":"completed","content":[{"type":"content","content":{"type":"text","text":"<path>{{cwd}}/greeting.txt</path>\n<type>file</type>\n<content>\n1: hello\n\n(End of file - total 1 lines)\n</content>"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"The"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" file"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":" contains"}}}}

examples/acp-agent/tests/snapshots/workspace-edit/system-prompt.golden.md

@@ -0,0 +1,19 @@
+You are an AI agent powered by the DeepSeek Harness SDK.
+
+You are a coding assistant powered by the deepseek-v4-flash model. Your working directory is {{cwd}}. Your bash tool runs under a file sandbox — a `[sandbox: file access denied …]` result is policy, not a command bug.
+
+Verify your work by running the code or tests. Keep answers brief and factual.
+
+
+Use the read tool — not shell commands like cat — to inspect text files. Results include line numbers. Use offset and limit to continue reading large files.
+
+Use the write tool to create files or completely replace file contents. Existing files are overwritten, so read an existing file first (the default fs-policy requires it) and prefer edit for targeted changes.
+
+Use the edit tool for targeted changes to existing UTF-8 text files. It replaces literal old_string with new_string; by default old_string must appear exactly once. If old_string appears multiple times, provide a more specific old_string or set replace_all to true. Read the file first (the default fs-policy requires it), unless you just created or edited it in this session.
+
+Check the [exit code: N] marker on every bash result; investigate failures before moving on.
+
+Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`).
+<!-- dsh-user-approval-policy:never -->
+
+Use the workflow tool ONLY when the user explicitly asks for a workflow or for large multi-agent orchestration: you write a JavaScript script (the tool description documents the exact format) that fans work out across many subagents with phases and structured results. For one or two delegations, prefer plain subagent calls.

package.json

@@ -49,6 +49,7 @@
     "verify-package-readme-limitations": "tsx scripts/verify-package-readme-limitations.ts",
     "verify-node-next-types": "tsx scripts/verify-node-next-types.ts",
     "verify-runtime-closure": "tsx scripts/verify-runtime-closure.ts",
+    "verify-cordis-config": "tsx scripts/verify-cordis-config.ts",
     "gen-cordis-catalog": "tsx scripts/gen-cordis-catalog.ts",
     "gen-rfc-index": "tsx scripts/gen-rfc-index.ts",
     "verify-cordis-catalog": "tsx scripts/gen-cordis-catalog.ts --check",
@@ -68,7 +69,7 @@
     "verify-module-graph": "tsx scripts/gen-module-graph.ts --check",
     "constraints": "tsx scripts/check-workspace-constraints.ts",
     "doc-sync": "pnpm run doc-typecheck && pnpm run verify-cordis-catalog && pnpm run verify-cordis-api && pnpm run verify-export-jsdoc && pnpm run verify-tool-catalog && pnpm run verify-config-catalog && pnpm run verify-persistence-catalog && pnpm run verify-doc-graphs && pnpm run verify-scoped-dispatch && pnpm run verify-md-wrap && pnpm run verify-md-links && pnpm run verify-doc-refs && pnpm run verify-package-paths && pnpm run verify-package-readme-model-experience && pnpm run verify-mermaid && pnpm run verify-rfc-classification && pnpm run verify-rfc-format && pnpm run verify-type-equiv && pnpm run verify-translation-pairing && pnpm run verify-doc-budgets && pnpm run verify-package-readme-limitations",
-    "hygiene": "pnpm run knip && pnpm run publint && pnpm run constraints && pnpm run verify-node-next-types && pnpm run verify-runtime-closure",
+    "hygiene": "pnpm run knip && pnpm run publint && pnpm run constraints && pnpm run verify-cordis-config && pnpm run verify-node-next-types && pnpm run verify-runtime-closure",
     "demo:echo": "node --expose-internals --import tsx packages/ui/stdio-agent/src/bin.ts examples/echo-agent/cordis.yml",
     "demo:repl": "node --expose-internals --import tsx packages/ui/stdio-agent/src/bin.ts examples/coding-agent/cordis.yml",
     "demo:code-mode": "node scripts/demo-code-mode.mjs",
@@ -79,6 +80,7 @@
   "devDependencies": {
     "@agentclientprotocol/sdk": "0.25.1",
     "@stylistic/eslint-plugin": "^5.10.0",
+    "@types/js-yaml": "^4.0.9",
     "@types/jsdom": "^28.0.3",
     "@types/mdast": "^4.0.4",
     "@types/node": "^22.20.0",
@@ -86,6 +88,7 @@
     "eslint": "^10.4.1",
     "eslint-plugin-sonarjs": "^4.1.0",
     "fast-check": "^4.8.0",
+    "js-yaml": "^4.2.0",
     "jscpd": "^5.0.12",
     "jsdom": "29.1.1",
     "knip": "^6.16.1",

packages/support/acp-snapshot/README.md

@@ -6,7 +6,7 @@ Three layers, importable separately:
 
 - **`runScenario` (harness)** — boots the real agent bin as a subprocess via tsx (unbuilt, Loader path), drives it over ACP JSON-RPC stdio from a deterministic `input.json` script, tees raw stdout for the golden + purity check, and harvests every persisted session JSONL (parent + subagent children, primary-first) after a graceful stdin-EOF shutdown. Parameterized by `AgentUnderTest` (`binScript`, `configPath`, `tsconfigPath` — absolute paths; the subprocess cwd is a temp dir outside the repo).
 - **Normalizers** — pure functions turning the two captured surfaces into stable text: `normalizeStdout` (JSON-RPC ids → first-seen sequence; UUIDs/cwd → tokens; doubles as the stdout-purity check), `normalizeSessionLog` (times zeroed, `seq` kept), `scrubSystemPrompts` (prompt text → `{{system}}` in every JSONL), and `scrubRequestHeaders` (the remaining header bulk → `{{tools}}`/`{{messagePrefix}}` outside each pin, structure kept — [pinned-header RFC](../../../docs/rfc/implemented/testing/2026-07-06-pin-request-header-content-in-one-scenario.md)).
-- **`defineAcpSnapshotSuite` (factory)** — registers the whole describe/it tree for a scenario table: per-scenario golden + re-persisted-log compares, record/refresh fixture write-back, the per-header-class pin (`system-prompt.golden.md` plus the JSONL's full tool schemas) with its live uniformity guard, and the fixture guard block (no orphan scenario dirs, required files present, exactly one pin per class, every JSONL prompt-scrubbed, non-pinning fixtures fully header-scrubbed). Must be called at vitest collection time.
+- **`defineAcpSnapshotSuite` (factory)** — registers the whole describe/it tree for a scenario table: per-scenario golden + re-persisted-log compares, record/refresh fixture write-back, rejection of structured `UNKNOWN_TOOL` results, the per-header-class pin (`system-prompt.golden.md` plus the JSONL's full tool schemas) with its live uniformity guard, and the fixture guard block (no orphan scenario dirs, required files present, exactly one pin per class, every JSONL prompt-scrubbed, non-pinning fixtures fully header-scrubbed). Must be called at vitest collection time.
 
 A consuming `*.snapshot.ts` is the scenario table plus one factory call:
 
@@ -35,7 +35,7 @@ defineAcpSnapshotSuite({
 })
 ```
 
-A scenario booting a differently-composed tree sets its own `configPath` (an overlay whose basename still ends in `cordis.yml`, so the bin's replay swap finds the sibling `*cordis.snapshot.yml`) and, when that composition changes the request header, its own `headerClass` with its own pinning scenario — the acp-agent example's Code Mode scenarios are the template. Each pinning directory's generated `system-prompt.golden.md` is the reviewable snapshot of the normalized composed prompt; `session.jsonl` stores `"system":"{{system}}"` while retaining the complete tool list.
+A scenario booting a differently-composed tree sets its own `configPath` (an overlay whose basename still ends in `cordis.yml`, so the bin's replay swap finds the sibling `*cordis.snapshot.yml`) and, when that composition changes the request header, its own `headerClass` with its own pinning scenario — the acp-agent example's Code Mode and filesystem scenarios are templates. Each pinning directory's generated `system-prompt.golden.md` is the reviewable snapshot of the normalized composed prompt; `session.jsonl` stores `"system":"{{system}}"` while retaining the complete tool list.
 
 Examples use a `cordis.snapshot.yml` overlay with [`dsh-llm-replay`](../llm-replay/README.md). Recording calls the live model and updates model fixtures; keyless refresh replays those fixtures and updates derived stdout, session-log, and prompt snapshots. See the [snapshot RFC](../../../docs/rfc/implemented/testing/2026-06-19-acp-snapshot-tests.md).
 

packages/support/acp-snapshot/src/suite.ts

@@ -274,6 +274,27 @@ function parseJsonlRecords(text: string): Record<string, unknown>[] {
     .map(line => JSON.parse(line) as Record<string, unknown>)
 }
 
+/**
+ * Find tool calls whose structured result reports `UNKNOWN_TOOL`.
+ *
+ * Snapshot refresh must not turn a missing registration into accepted behavior;
+ * intentional unknown-tool behavior belongs in a focused unit or e2e test.
+ *
+ * @param rawLog The session JSONL to inspect.
+ * @returns The failing call ids in log order, using a diagnostic placeholder when absent.
+ */
+export function unknownToolCallIds(rawLog: string): string[] {
+  return parseJsonlRecords(rawLog).flatMap((record) => {
+    if (record.type !== 'tool/result') return []
+    const data = record.data
+    if (data === null || typeof data !== 'object') return []
+    const { callId, error } = data as { callId?: unknown; error?: unknown }
+    if (error === null || typeof error !== 'object') return []
+    if ((error as { code?: unknown }).code !== 'UNKNOWN_TOOL') return []
+    return [typeof callId === 'string' ? callId : '<missing callId>']
+  })
+}
+
 /**
  * Build the cross-log id/cwd replacements used by refresh write-back.
  *
@@ -401,6 +422,11 @@ export function defineAcpSnapshotSuite(options: SnapshotSuiteOptions): void {
           ...scenario.configPath !== undefined ? { configPath: scenario.configPath } : {},
         })
 
+        for (const log of result.sessionLogs) {
+          expect(unknownToolCallIds(log.content), `session ${log.id}: snapshot scenarios must not accept UNKNOWN_TOOL`)
+            .toEqual([])
+        }
+
         // Scrub every volatile id the run produced: the ACP server-issued session id plus every
         // harvested log's recorded id (a subagent child id never surfaces over ACP, but it
         // appears in the child's own log header).
@@ -598,5 +624,20 @@ export function defineAcpSnapshotSuite(options: SnapshotSuiteOptions): void {
         }
       }
     })
+
+    it('no committed session fixture accepts UNKNOWN_TOOL', async () => {
+      for (const scenario of scenarios) {
+        const dir = join(snapshotsDir, scenario.name)
+        const files = [
+          'session.jsonl',
+          ...Array.from({ length: scenario.childSessions ?? 0 }, (_, i) => `session.${i + 1}.jsonl`),
+        ]
+        for (const file of files) {
+          const fixture = await readFile(join(dir, file), 'utf8')
+          expect(unknownToolCallIds(fixture), `${scenario.name}/${file} contains UNKNOWN_TOOL`)
+            .toEqual([])
+        }
+      }
+    })
   })
 }

packages/support/acp-snapshot/tests/suite.spec.ts

@@ -15,6 +15,7 @@ import {
   normalizedSystemPrompts,
   refreshFixtureReplacements,
   stabilizeRefreshLog,
+  unknownToolCallIds,
 } from '../src/suite.ts'
 
 /**
@@ -278,6 +279,27 @@ describe('headerDeltaCount', () => {
   })
 })
 
+describe('unknownToolCallIds', () => {
+  it('returns structured UNKNOWN_TOOL call ids and ignores other results', () => {
+    const log = [
+      '{"type":"tool/result","data":{"callId":"missing","error":{"code":"UNKNOWN_TOOL"}}}',
+      '{"type":"tool/result","data":{"callId":"failed","error":{"code":"EXECUTION_FAILED"}}}',
+      '{"type":"tool/result","data":null}',
+      '{"type":"tool/result","data":"invalid"}',
+      '{"type":"tool/result","data":{"error":null}}',
+      '{"type":"tool/result","data":{"error":"invalid"}}',
+      '{"type":"assistant/message","data":{"error":{"code":"UNKNOWN_TOOL"}}}',
+      '{"type":"tool/result","data":{"error":{"code":"UNKNOWN_TOOL"}}}',
+      '',
+    ].join('\n')
+    expect(unknownToolCallIds(log)).toEqual(['missing', '<missing callId>'])
+  })
+
+  it('returns no failures for ordinary tool results', () => {
+    expect(unknownToolCallIds('{"type":"tool/result","data":{"callId":"ok"}}\n')).toEqual([])
+  })
+})
+
 describe('refreshFixtureReplacements', () => {
   it('maps fresh ids and cwd values to the existing fixture values, skipping non-replacements', () => {
     const log = (content: string): HarvestedLog => ({ id: 'diagnostic', createdAt: 1, content })

pnpm-lock.yaml

@@ -14,6 +14,9 @@ importers:
       '@stylistic/eslint-plugin':
         specifier: ^5.10.0
         version: 5.10.0(eslint@10.5.0(jiti@2.7.0))
+      '@types/js-yaml':
+        specifier: ^4.0.9
+        version: 4.0.9
       '@types/jsdom':
         specifier: ^28.0.3
         version: 28.0.3
@@ -35,6 +38,9 @@ importers:
       fast-check:
         specifier: ^4.8.0
         version: 4.8.0
+      js-yaml:
+        specifier: ^4.2.0
+        version: 4.2.0
       jscpd:
         specifier: ^5.0.12
         version: 5.0.12
@@ -1280,28 +1286,6 @@ importers:
         specifier: ^4.0.0-rc.6
         version: 4.0.0-rc.6(@cordisjs/plugin-include@vendor+include)(@cordisjs/plugin-loader@vendor+loader)
 
-  packages/ui/permission:
-    dependencies:
-      schemastery:
-        specifier: ^3.18.0
-        version: 3.18.0
-    devDependencies:
-      '@deepseek-ai/dsh-bash':
-        specifier: workspace:^
-        version: link:../../bash/bash
-      '@deepseek-ai/dsh-sandbox':
-        specifier: workspace:^
-        version: link:../../sandbox/sandbox
-      '@deepseek-ai/dsh-session':
-        specifier: workspace:^
-        version: link:../../core/session
-      '@deepseek-ai/dsh-user-approval':
-        specifier: workspace:^
-        version: link:../user-approval
-      cordis:
-        specifier: ^4.0.0-rc.6
-        version: 4.0.0-rc.6(@cordisjs/plugin-include@1.0.4)(@cordisjs/plugin-loader@1.0.0-rc.4)
-
   packages/ui/jsonrpc:
     dependencies:
       schemastery:
@@ -1346,6 +1330,28 @@ importers:
         specifier: ^4.0.0-rc.6
         version: 4.0.0-rc.6(@cordisjs/plugin-include@1.0.4)(@cordisjs/plugin-loader@1.0.0-rc.4)
 
+  packages/ui/permission:
+    dependencies:
+      schemastery:
+        specifier: ^3.18.0
+        version: 3.18.0
+    devDependencies:
+      '@deepseek-ai/dsh-bash':
+        specifier: workspace:^
+        version: link:../../bash/bash
+      '@deepseek-ai/dsh-sandbox':
+        specifier: workspace:^
+        version: link:../../sandbox/sandbox
+      '@deepseek-ai/dsh-session':
+        specifier: workspace:^
+        version: link:../../core/session
+      '@deepseek-ai/dsh-user-approval':
+        specifier: workspace:^
+        version: link:../user-approval
+      cordis:
+        specifier: ^4.0.0-rc.6
+        version: 4.0.0-rc.6(@cordisjs/plugin-include@1.0.4)(@cordisjs/plugin-loader@1.0.0-rc.4)
+
   packages/ui/stdio-agent:
     devDependencies:
       '@cordisjs/plugin-include':
@@ -3145,6 +3151,9 @@ packages:
   '@types/geojson@7946.0.16':
     resolution: {integrity: sha512-6C8nqWur3j98U6+lXDfTUWIfgvZU+EumvpHKcYjujKH7woYyLj2sUmff0tRhrqM7BohUw7Pz3ZB1jj2gW9Fvmg==}
 
+  '@types/js-yaml@4.0.9':
+    resolution: {integrity: sha512-k4MGaQl5TGo/iipqb2UDG2UwjXziSWkh0uysQelTlJpX1qGlpUZYm8PnO4DxG1qBomtJUdYJ6qR6xdIah10JLg==}
+
   '@types/jsdom@28.0.3':
     resolution: {integrity: sha512-/HQ2uFoetFTXuye8vzIcHw2z6Fwi7Hi/qcgC+RoS9NCyewiqxhVGqlG+ViGB6lkax481R6dmhf1I7lIGlzJStQ==}
 
@@ -5985,6 +5994,8 @@ snapshots:
 
   '@types/geojson@7946.0.16': {}
 
+  '@types/js-yaml@4.0.9': {}
+
   '@types/jsdom@28.0.3':
     dependencies:
       '@types/node': 25.9.3

scripts/doc-budgets.manifest.json

@@ -2,7 +2,7 @@
   "AGENTS.md": 1370,
   "docs/AGENTS.md": 1100,
   "docs/architecture.md": 1790,
-  "docs/cordis-primer.md": 550,
+  "docs/cordis-primer.md": 600,
   "docs/defensive-patterns.md": 550,
   "docs/testing.md": 800,
   "examples/AGENTS.md": 200,

scripts/run-gates.ts

@@ -153,6 +153,7 @@ function gatesForMode(selected: Mode): Gate[] {
     case 'pre-push':
       return [
         pnpmScript('runtime-closure', 'verify-runtime-closure', { label: 'runtime closure' }),
+        pnpmScript('cordis-config', 'verify-cordis-config', { label: 'Cordis config' }),
         pnpmScript('test', 'test'),
         pnpmScript('duplication', 'duplication'),
         pnpmScript('snapshot', 'test:snapshot'),
@@ -168,6 +169,7 @@ function ciPrimaryGates(): Gate[] {
   return [
     pnpmScript('runtime-closure', 'verify-runtime-closure', { label: 'runtime closure' }),
     pnpmScript('constraints', 'constraints'),
+    pnpmScript('cordis-config', 'verify-cordis-config', { label: 'Cordis config' }),
     pnpmScript('typecheck', 'typecheck'),
     lintGate(),
     pnpmScript('duplication', 'duplication'),
@@ -191,6 +193,7 @@ function ciStaticGates(): Gate[] {
   return [
     pnpmScript('runtime-closure', 'verify-runtime-closure', { label: 'runtime closure' }),
     pnpmScript('constraints', 'constraints'),
+    pnpmScript('cordis-config', 'verify-cordis-config', { label: 'Cordis config' }),
     demoSmokeGate(),
     ...docSyncLeafGates(),
     pnpmScript('module-graph', 'verify-module-graph', { label: 'module graph' }),

scripts/verify-cordis-config.ts

@@ -0,0 +1,111 @@
+/**
+ * Reject JavaScript expressions in Cordis Loader entry metadata.
+ *
+ * The Loader interpolates only a plugin entry's `config`; expression objects in
+ * fields such as `disabled` remain truthy data and silently change composition.
+ */
+
+import { globSync, readFileSync } from 'node:fs'
+import { resolve } from 'node:path'
+import * as yaml from 'js-yaml'
+
+interface JsExpr {
+  __jsExpr: string
+}
+
+const root = resolve(import.meta.dirname, '..')
+const metadataFields = ['id', 'name', 'group', 'disabled', 'inject', 'intercept', 'isolate'] as const
+const jsExprType = new yaml.Type('tag:yaml.org,2002:js', {
+  kind: 'scalar',
+  resolve: data => typeof data === 'string',
+  construct: (data: unknown): JsExpr => {
+    if (typeof data !== 'string') throw new TypeError('!!js requires a scalar string')
+    return { __jsExpr: data }
+  },
+})
+const schema = yaml.JSON_SCHEMA.extend(jsExprType)
+
+const files = globSync(['**/*cordis*.yml', '**/*cordis*.yaml'], {
+  cwd: root,
+  exclude: ['.claude/**', 'node_modules/**', 'vendor/**'],
+}).sort()
+const errors: string[] = []
+
+for (const file of files) {
+  const document: unknown = yaml.load(readFileSync(resolve(root, file), 'utf8'), { schema })
+  if (!isUnknownArray(document)) {
+    errors.push(`${file}: root must be a Loader entry array`)
+    continue
+  }
+  for (let index = 0; index < document.length; index++) {
+    validateEntry(document[index], file, `[${index}]`)
+  }
+}
+
+if (errors.length > 0) {
+  console.error('verify-cordis-config: Loader entry metadata is static; move !!js under plugin config or select an explicit overlay.')
+  for (const error of errors) console.error(`- ${error}`)
+  process.exitCode = 1
+} else {
+  console.log(`verify-cordis-config: ${files.length} config files passed.`)
+}
+
+function validateEntry(value: unknown, file: string, path: string): void {
+  if (!isRecord(value)) {
+    errors.push(`${file}${path}: entry must be an object`)
+    return
+  }
+  validateMetadata(value, file, path)
+  if ((value.group === true || value.name === '@cordisjs/plugin-group') && isUnknownArray(value.config)) {
+    for (let index = 0; index < value.config.length; index++) {
+      validateEntry(value.config[index], file, `${path}.config[${index}]`)
+    }
+  }
+  if (value.name !== '@cordisjs/plugin-include') return
+  const config = value.config
+  if (!isRecord(config) || !isUnknownArray(config.patches)) return
+  for (let index = 0; index < config.patches.length; index++) {
+    const patch = config.patches[index]
+    const patchPath = `${path}.config.patches[${index}]`
+    if (!isRecord(patch)) continue
+    validateMetadata(patch, file, patchPath)
+    if (!isUnknownArray(patch.insert)) continue
+    for (let insertIndex = 0; insertIndex < patch.insert.length; insertIndex++) {
+      validateEntry(patch.insert[insertIndex], file, `${patchPath}.insert[${insertIndex}]`)
+    }
+  }
+}
+
+function validateMetadata(entry: Record<string, unknown>, file: string, path: string): void {
+  for (const field of metadataFields) {
+    if (!(field in entry)) continue
+    const expressionPaths: string[] = []
+    collectExpressionPaths(entry[field], `${path}.${field}`, expressionPaths)
+    for (const expressionPath of expressionPaths) errors.push(`${file}${expressionPath}: !!js is not interpolated here`)
+  }
+}
+
+function collectExpressionPaths(value: unknown, path: string, output: string[]): void {
+  if (isJsExpr(value)) {
+    output.push(path)
+    return
+  }
+  if (isUnknownArray(value)) {
+    for (let index = 0; index < value.length; index++) collectExpressionPaths(value[index], `${path}[${index}]`, output)
+    return
+  }
+  if (!isRecord(value)) return
+  for (const [key, child] of Object.entries(value)) collectExpressionPaths(child, `${path}.${key}`, output)
+}
+
+function isJsExpr(value: unknown): value is JsExpr {
+  return isRecord(value) && typeof value.__jsExpr === 'string'
+}
+
+function isRecord(value: unknown): value is Record<string, unknown> {
+  return value !== null && typeof value === 'object'
+}
+
+function isUnknownArray(value: unknown): value is unknown[] {
+  return Array.isArray(value)
+}