Unable to connect to certain MCPs, including the Mobbin MCP #27799

What version of the Codex App are you using (From “About Codex” dialog)?

Version 26.609.30741 • Released 11 Jun 2026

What subscription do you have?

Pro Max 20x

What platform is your computer?

Windows

What issue are you seeing?

I asked Codex to investigate the issue and it reported this: (this was happening on earlier versions of Codex as well)

I confirmed the saved Mobbin OAuth token is valid.
Using the token from C:\Users\chris.codex.credentials.json, a direct MCP initialize request to https://api.mobbin.com/mcp returned:
HTTP/1.1 200 OK
Content-Type: text/event-stream

serverInfo: mobbin
protocolVersion: 2025-06-18
capabilities: resources, tools
So the cause is not Mobbin rejecting the saved token. The token works.
That narrows it to a Codex-side issue: during MCP startup, Codex is not attaching the saved Mobbin bearer token to the initialize request, or it is starting Mobbin through a path that does not read .credentials.json.
The clean bug report evidence is:
Config:
[mcp_servers.mobbin]
url = "https://api.mobbin.com/mcp"

Saved credential:
server_name=mobbin
server_url=https://api.mobbin.com/mcp
access_token_present=True
refresh_token_present=True

Direct initialize with saved access_token:
HTTP 200 OK, serverInfo.name=mobbin

Codex MCP startup:
Auth error: OAuth authorization required, when send initialize request
That is a Codex MCP credential loading/attachment bug, not a Mobbin OAuth-save failure.

What steps can reproduce the bug?

Feedback ID: 019eb8a7-e409-7192-9cd8-953c831bfc39

What is the expected behavior?

I'm able to connect to the Mobbin MCP

Additional information

Feedback issue: 019eb8a7-e409-7192-9cd8-953c831bfc39