For our GPT - signing in isn't prompted on the mobile apps (it works fine on Web)

GPT builders
,
1

I have developed a GPT that requires auth to connect to the API. On web, you prompt something and it immediately prompts you to sign in. In the mobile apps, it just says (eventually) “Stopped talking to api-url” - has anyone else had this issue? We have WWW-authenticate firing.

2

Hey @tomking, that’s confusing, and you’re not the only one seeing web and mobile behave differently here.

Most likely, mobile isn’t surfacing the GPT Action OAuth sign-in challenge properly. For Actions, auth should be configured as OAuth in the GPT editor so ChatGPT shows the “Sign in to [domain]” flow. I wouldn’t rely on WWW-Authenticate alone to trigger login.

A few things to double-check:

  • OAuth is configured in the GPT Action settings
  • Both callback URLs are allowlisted:
  • chat.openai.com/aip/{GPT_ID}/oauth/callback
  • chatgpt.com/aip/{GPT_ID}/oauth/callback
  • Token response includes the expected fields like access_token, token_type, and optionally refresh_token / expires_in

If all of that is set and mobile still only says “Stopped talking to api-url,” I’d treat it as a mobile client parity bug and open a support ticket with a repro.

-Mark G.