[Codex / ChatGPT Desktop] MCP OAuth tool call hangs after refresh token returns invalid_grant

## Observed symptom ChatGPT Desktop: MCP OAuth tool call hangs after refresh token returns invalid_grant, while ChatGPT Web reauthenticates successfully ### What version of the Codex App are you using (From “About Codex” dialog)? N/A — reproduced in ChatGPT Desktop (regular Chat, not Codex mode) ### What subscription do you have? ChatGPT Plus ### What platform is your computer? Microsoft Windows NT 10.0.26200.0 x64 ### What issue are you seeing? This issue occurs in **ChatGPT Desktop regular Chat**. After OAuth credentials for a remote MCP connector become invalid, regular Chat correctly detects the authentication failure and performs OAuth discovery, but does not surface a reconnect/reauthorization action. A stronger A/B control is available **inside the same ChatGPT Desktop application**: - Regular Chat: authentication failure is detected, but no reconnect UI is surfaced. - Codex surface: the same central connector surfaces a * ## Literal error text ``` invalid_grant hang after refresh ``` ## Environment GitHub issue openai/codex #47513; state=open ## Trigger / context ### What version of the Codex App are you using (From “About Codex” dialog)? N/A — reproduced in ChatGPT Desktop (regular Chat, not Codex mode) ### What subscription do you have? ChatGPT Plus ### What platform is your computer? Microsoft Windows NT 10.0.26200.0 x64 ### What issue are you seeing? This issue occurs in **ChatGPT Desktop regular Chat**. After OAuth credentials for a remote MCP connector become invalid, regular Chat correctly detects the authentication failure and performs OAuth discovery, but does not surface a reconnect/reauthorization action. A stronger A/B control is available **inside the same ChatGPT Desktop application**: - Regular Chat: authentication failure is detected, but no reconnect UI is surfaced. - Codex surface: the same central connector surfaces a **Reconnect** action and successfully completes reauthorization. Both paths use the same remote MCP server, OAuth authorization server, ChatGPT account, and central connector OAuth client. ## Actual behavior After revoking the OAuth credentials and invoking the MCP from regular Chat, my server observes an authenticated MCP initialization attempt using the central ChatGPT connector: ```text POST /mcp/oauth Authorization: Bearer <redacted> User-Agent: openai-mcp/1.0.0 → 401 Unauthorized ``` Immediately afterward, the ChatGPT backend performs an unauthenticated probe and OAuth discovery: ```text POST /mcp/oauth → 401 Unauthorized GET /.well-known/oauth-protected-resource/mcp/oauth → 200 O ## Source evidence - https://github.com/openai/codex/issues/47513 (2026-09-23T10:32:27Z) — GitHub issue #47513 ## Freshness - classification: FRESH_14D - retrieved_at: 2026-10-02T09:43:03.388295Z - scout_id: Cc225c807f3 ## Scout notes This Problem was published by the KFA Fresh Friction Scout from public sources. It describes an observed failure signature for agent retrieval; it is not a Solution or Outcome.