Desktop can submit the next turn before Plan mode transition commits

[liugddx]

What happened

Maka Desktop can display Plan mode as active while the next root turn is still admitted with collaborationMode: 'agent'.

In the observed flow:

1. A Plan was submitted, approved, and executed.
2. Runtime returned the Session to Agent mode for execution.
3. Plan mode was enabled again from the Desktop composer.
4. A new message was sent immediately after enabling Plan mode.
5. The composer displayed Plan mode as selected, but the new turn behaved as an ordinary Agent turn:
   • no new Plan proposal or approval card was produced;
   • the Plan workflow was unavailable to the assistant;
   • the assistant incorrectly told the user that the Session was still in ordinary execution mode.

This creates a split-brain state: the Desktop UI says Plan, but the admitted AgentRun uses Agent mode.

Expected behavior:

Once the composer displays Plan mode as selected, the next submitted root turn must either:

• be admitted with collaborationMode: 'plan'; or
• remain blocked until the Plan mode transition has committed.

Maka should never silently start a turn in Agent mode while the composer displays Plan mode.

How to reproduce

The issue appears timing-sensitive.

1. Open an existing Desktop Session in Agent mode.

2. Enable Plan mode from the composer.

3. Immediately submit a message that requires a Plan proposal, for example:

   Create maka-plan-demo.md, read it back for verification, and track each execution step. Start by submitting a plan for approval.

4. Observe that the composer displays Plan mode as selected.

5. Observe that the new turn may behave as an ordinary Agent turn instead of submitting a Plan proposal.

The issue was originally observed with this sequence:

1. Enter Plan mode.
2. Submit a Plan.
3. Approve and execute the Plan.
4. Finish the execution, which returns the Session to Agent mode.
5. Enable Plan mode again.
6. Immediately send another message.
7. The UI displays Plan, but the new turn behaves as Agent.

For a deterministic regression test:

1. Delay the sessions:setCollaborationMode IPC response.
2. Click the Plan toggle.
3. Submit a message before the IPC response resolves.
4. Verify that the turn is not admitted using the previous agent mode.

Environment

Maka Desktop diagnostic report
Captured at: 2026-09-03T23:22:32.778Z

Capture
Surface: manual

Environment
Maka: 0.2.0-dev.15.20260902
Build: packaged
Channel: nightly
Electron: 43.4.1
Chrome: 150.0.7871.224
Node: 24.18.1
OS: win32 10.0.19042 (x64)
Locale: zh-CN
Renderer locale: zh-CN
Renderer user agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Maka/0.2.0-dev.15.20260902 Chrome/150.0.7871.224 Electron/43.4.1 Safari/537.36
Workspace: ~\AppData\Roaming\Maka\workspaces\default
Main process uptime: 79924s

Recent main-process logs (9)
[2026-09-03T01:10:28.654Z] LOG [startup] app ready
[2026-09-03T01:10:41.400Z] ERROR (node:34424) [DEP0180] DeprecationWarning: fs.Stats constructor is deprecated.
(Use Maka --trace-deprecation ... to show where the warning was created)
[2026-09-03T07:29:09.914Z] ERROR Error occurred in handler for 'sessions:transcript:open': Error: Transcript observation ended before it became ready
at #deleteTranscript (file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-session-observation-registry.js:396:35)
at RuntimeHostSessionObservationRegistry.closeTranscript (file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-session-observation-registry.js:280:31)
at file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-desktop-manager.js:233:95
at Array.map ()
at RuntimeHostDesktopManagerImpl.closeTranscript (file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-desktop-manager.js:233:60)
at file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-boot.js:1406:35
at Session. (node:electron/js2c/browser_init:2:118387)
at Session.emit (node:events:509:28)
[2026-09-03T15:34:57.789Z] ERROR Error occurred in handler for 'sessions:transcript:open': Error: Transcript observation ended before it became ready
at #deleteTranscript (file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-session-observation-registry.js:396:35)
at RuntimeHostSessionObservationRegistry.closeTranscript (file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-session-observation-registry.js:280:31)
at file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-desktop-manager.js:233:95
at Array.map ()
at RuntimeHostDesktopManagerImpl.closeTranscript (file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-desktop-manager.js:233:60)
at file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-boot.js:1406:35
at Session. (node:electron/js2c/browser_init:2:118387)
at Session.emit (node:events:509:28)
[2026-09-03T15:34:57.796Z] ERROR Error occurred in handler for 'sessions:observe': Error: Session observation ended before it became ready
at #deleteRegistration (file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-session-observation-registry.js:319:35)
at #remove (file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-session-observation-registry.js:311:33)
at RuntimeHostSessionObservationRegistry.unobserve (file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-session-observation-registry.js:207:27)
at file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-desktop-manager.js:230:95
at Array.map ()
at RuntimeHostDesktopManagerImpl.unobserveSession (file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-desktop-manager.js:230:60)
at file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-boot.js:1400:35
at Session. (node:electron/js2c/browser_init:2:118387)
at Session.emit (node:events:509:28)
[2026-09-03T15:34:57.796Z] ERROR Error occurred in handler for 'sessions:observe': Error: Session observation ended before it became ready
at #deleteRegistration (file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-session-observation-registry.js:319:35)
at #remove (file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-session-observation-registry.js:311:33)
at RuntimeHostSessionObservationRegistry.unobserve (file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-session-observation-registry.js:207:27)
at file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-desktop-manager.js:230:95
at Array.map ()
at RuntimeHostDesktopManagerImpl.unobserveSession (file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-desktop-manager.js:230:60)
at file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-boot.js:1400:35
at Session. (node:electron/js2c/browser_init:2:118387)
at Session.emit (node:events:509:28)
[2026-09-03T23:13:27.347Z] ERROR Error occurred in handler for 'sessions:transcript:open': Error: Transcript observation ended before it became ready
at #deleteTranscript (file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-session-observation-registry.js:396:35)
at RuntimeHostSessionObservationRegistry.closeTranscript (file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-session-observation-registry.js:280:31)
at file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-desktop-manager.js:233:95
at Array.map ()
at RuntimeHostDesktopManagerImpl.closeTranscript (file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-desktop-manager.js:233:60)
at file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-boot.js:1406:35
at Session. (node:electron/js2c/browser_init:2:118387)
at Session.emit (node:events:509:28)
[2026-09-03T23:13:27.431Z] ERROR Error occurred in handler for 'sessions:observe': Error: Session observation ended before it became ready
at #deleteRegistration (file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-session-observation-registry.js:319:35)
at #remove (file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-session-observation-registry.js:311:33)
at RuntimeHostSessionObservationRegistry.unobserve (file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-session-observation-registry.js:207:27)
at file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-desktop-manager.js:230:95
at Array.map ()
at RuntimeHostDesktopManagerImpl.unobserveSession (file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-desktop-manager.js:230:60)
at file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-boot.js:1400:35
at Session. (node:electron/js2c/browser_init:2:118387)
at Session.emit (node:events:509:28)
[2026-09-03T23:13:27.432Z] ERROR Error occurred in handler for 'sessions:observe': Error: Session observation ended before it became ready
at #deleteRegistration (file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-session-observation-registry.js:319:35)
at #remove (file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-session-observation-registry.js:311:33)
at RuntimeHostSessionObservationRegistry.unobserve (file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-session-observation-registry.js:207:27)
at file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-desktop-manager.js:230:95
at Array.map ()
at RuntimeHostDesktopManagerImpl.unobserveSession (file:////AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-desktop-manager.js:230:60)
at file:///~/AppData/Local/Programs/@makadesktop/resources/app.asar/dist/main/runtime-host-boot.js:1400:35
at Session. (node:electron/js2c/browser_init:2:118387)
at Session.emit (node:events:509:28)

Recent local Runtime Host process exits (0)

Runtime Host
Epoch: c2890f54-ab69-42bb-a09f-bdd6fbecac06
Protocol: v0 · compatibility 96
State: ready
Process: 37272 · uptime 79918s
Runtime: Node 24.18.1 · win32 10.0.19042 (x64)
Activity: 1 connections · 1 operations · 1 residencies
Recent Runtime Host logs (2)
[2026-09-03T01:10:38.928Z] ERROR [runtime-host] models.dev no longer carries 4 path(s) the bundled snapshot described; adopting upstream: /metadata/openrouter/anthropic1claude-opus-4.7-fast, /metadata/openrouter/anthropic1claude-opus-4.8-fast, /metadata/openrouter/anthropic1claude-opus-5-fast, /metadata/vercel/deepseek1deepseek-v3
[2026-09-03T08:50:00.586Z] ERROR (node:37272) [DEP0180] DeprecationWarning: fs.Stats constructor is deprecated.
(Use Maka --trace-deprecation ... to show where the warning was created)

Logs, screenshots, or additional context

No response

[testikun]

I would like to take this issue.

I will keep the first PR focused on the Plan-mode transition race:

• represent the collaboration-mode write as pending and prevent the next root-turn submission from using the previous mode while the UI already shows Plan;
• admit the send only after sessions:setCollaborationMode succeeds;
• on rejection, restore the authoritative mode, preserve the draft, and surface the existing actionable error;
• add a deterministic renderer regression with a delayed IPC response, plus the focused Desktop interaction coverage.

This will not change Plan approval or execution semantics, and it will not bundle unrelated composer state changes.

中文摘要：我认领这个问题。首个 PR 只修复 Plan 模式切换尚未提交时仍可发送下一轮的竞态，并补延迟 IPC 的确定性测试。

Claimed with OpenAI Codex assistance on behalf of @testikun.

[liugddx]

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