ChatGPT desktop Chat/Work loses installed skills during authentication verification 503s

What version of the ChatGPT/Codex desktop app are you using?

ChatGPT desktop app 26.814.41407
Bundled Codex CLI 0.148.0-alpha.15

What subscription do you have?

ChatGPT Pro

What platform is your computer?

macOS 15.5 (24F74), Apple Silicon

What issue are you seeing?

Installed local skills are available and callable in a Codex task, but Chat/Work conversations in the same desktop app incorrectly claim that the skills cannot be used or that no execution path is available.

A concrete example is the local jquants-jp-stock skill:

• The skill exists locally and has allow_implicit_invocation: true.
• It successfully ran from a Codex task in this same app/account and retrieved current J-Quants data.
• Chat/Work conversations nevertheless stated that the skill could not be invoked from the conversation.
• The behavior also affects other skills/APIs, so this does not appear to be a defect in the individual skill.

The desktop logs at the time of failure show repeated backend/authentication and conversation-state errors:

status=503
{"detail":"Unable to fetch authentication verification keys."}
routePattern=/ios/attestation_challenge
routePattern=/conversations

They also show:

Received turn/started for unknown conversation
Received turn/completed for unknown conversation
Conversation state not found
Too many concurrent requests

The 503s occurred across multiple ChatGPT endpoints, while a local Codex task continued to see and use the installed skill. This suggests an authentication/session/plugin-capability reconciliation failure on the Chat/Work surface, rather than a broken skill installation.

The public OpenAI status page did not list an incident for the affected period.

When did this occur?

Observed on August 19–20, 2026 (Asia/Tokyo).
Representative log time: 2026-08-19T23:52:42Z through at least 2026-08-19T23:59:59Z.

Steps to reproduce

1. Install/enable a local skill with implicit invocation allowed.
2. Confirm the skill works in a Codex task in the ChatGPT desktop app.
3. Open a normal Chat or Work conversation in the same app/account.
4. Ask it to use the same skill.
5. Observe that Chat/Work claims the skill is unavailable or cannot be called.
6. Inspect the desktop logs and observe authentication verification-key 503s and/or stale/unknown conversation-state errors.

Expected behavior

Chat, Work, and Codex should reconcile the same authenticated skill/plugin capability state where that capability is supported. If authentication or capability synchronization fails, the app should surface a clear transient service error instead of telling the user that a valid installed skill cannot be used.

Additional information

• Restarting/reconnecting did not reliably resolve the issue.
• No skill files were modified during diagnosis.
• Full logs are not attached publicly because they may contain account/session metadata, but sanitized excerpts are included above.

Start by reproducing the report with a local skill that allows implicit invocation, comparing a Codex task with a Chat or Work conversation. Inspect the desktop logs around /ios/attestation_challenge and /conversations, including the authentication 503 and unknown-conversation messages. Done means supported conversations retain the installed capability or show a clear transient service error instead of reporting the skill as unavailable.