ChatGPT web version cannot connect to custom MCP

ChatGPT Apps SDK
1

I’ve built my own MCP server that uses OAuth 2.1, supports CIDM and DCR, and uses Streamable HTTP and OIDC, etc. I’ve confirmed that I’ve configured HTTPS and other components and referred to existing documentation. Currently, I’ve noticed that after receiving the callback, ChatGPT doesn’t attempt to retrieve the token from the POST /token endpoint, but instead displays the message “There was a problem connecting [mcp name]. Try again later.” This MCP works fine in Codex, but fails in the web version.

How should I troubleshoot this? How can I retrieve the logs or find out why ChatGPT isn’t continuing to attempt the MCP’s OAuth authentication process?

2

Thanks for the detailed report, @Sunwuyuan. There was a recent issue posted on the OpenAI Status Page that may have affected the MCP OAuth flow you were seeing.

Are you still running into this? If so, please record a HAR file and send it to support@openai.com along with:

  • The exact timestamp of the failed attempt in UTC
  • A snippet of the callback response
  • Any relevant request or correlation IDs

Once submitted, drop the case ID here so the team can help monitor and investigate it.

-Mark G.