Codex app cannot create a new task from a devbox after create_thread tool migration
Codex App version
ChatGPT Nightly, restarted and updated immediately before the second reproduction. The exact About-dialog version is not available from inside the remote task.
Remote Codex CLI: 0.150.0-alpha.3 on the alpha track.
Subscription
OpenAI employee workspace.
Platform
macOS ChatGPT desktop app connected to a remote Linux devbox.
What issue are you seeing?
A Codex task running on a remote devbox cannot create another user-visible task. Project discovery succeeds, and other Codex app task tools such as list_projects and set_thread_title work, but create_thread fails before creating anything with this exact error:
This app tool is no longer available through dynamic tools. Use the codex_app MCP server. If that server is unavailable on this host, task delegation is unavailable.
No task or worktree is created.
Steps to reproduce
- Open a repository task in the ChatGPT desktop app using a remote Linux devbox.
- Ask Codex to start a separate task for a bounded investigation.
- Codex calls list_projects successfully and resolves the remote Git repository.
- Codex calls create_thread with a project target and worktree environment.
- The call returns the migration error above.
- Fully quit and restart the desktop app, update it, reopen the remote task, refresh the project inventory, and retry.
- The same error occurs.
Session ID: 01a0209f-a999-7dc3-bcae-eb0fdae4efd9
Expected behavior
create_thread should create the requested user-visible task on the selected remote project and return a thread ID or queued client thread ID.
Additional information
- Reproduced multiple times before and after restarting/updating the desktop app.
- list_projects and set_thread_title continue to work in the same task.
- The devbox Codex CLI is already on a current alpha build, so this appears to be a desktop-app/tool-routing version mismatch rather than an outdated devbox CLI.
- I searched openai/codex issues for the exact error, codex_app MCP server, create_thread, devbox, and task delegation before filing and found no matching report.
- No logs are attached because this task contains internal production investigation context.