I’ve been running my ChatGPT app locally, and it was working fine yesterday morning. However, starting around noon, I began getting the error message “Hmm…something seems to have gone wrong” whenever I prompt the app with any question.
This issue only occurs in developer mode. Has anyone else experienced this problem?
Seeing this now too! Currently cannot do anything in developer mode. Started for me about 20mins ago.
Still broken 
There is an issue, that is blocking service we paid for! 
Any ETA for the fix? 
Hi im sorry but i dont know what to do I’m experiencing a serious issue with my main OpenAI account. About 4 h before the error started, everything was working normally. Then suddenly, I became unable to send any messages to the assistant. I can type in the message box, but when I press “Send,” I immediately get an error such as: “Hmm… something seems to have gone wrong. This happens everywhere, including: the web version (Chrome), the mobile app, on Wi-Fi and on mobile data, and on different devices. I tested another account on the same devices and network, and that account works normally, which suggests the issue is specific to my main account. I have already tried: clearing cache & cookies, restarting the browser and app, switching networks, reinstalling the mobile app, using a different device. Nothing helped. Did you know how to fix it ? It’s “plus” versionand and I’m honestly afraid that it will stay like this forever
@OpenAI_Support This is still an issue for me. Seems to be related to having my app enabled as error disappears when disconnected. App connects and logs in with no problem and shows all tools fine, no errors on my server. Browser inspector showing 500. Locally mcp inspector runs fine and all tools work.
Unfortunately, I cant provide any more info into whats causing the error as it’s quite difficult to debug when all we get is “Hmm…something seems to have gone wrong”. It would be really nice if you could expose some more debugging to developers when in developer mode!
We encountered this error as well, and the issue turned out to be in the JSON schema. Even though each tool had a valid schema according to the MCP inspector, ChatGPT’s JSON validator rejects certain patterns. In our case, the problem was optional arrays—specifically fields defined as either "array" or "null".
If any tool contains a schema that ChatGPT does not accept, none of the tools will work. And as long as that connector remains added to your account, you won’t be able to use ChatGPT normally.
Hi @hanna_grunt . I remember using a stricter JSON schema when developing AI agents. It makes sense that here as well we would need to adhere to it.
https://platform.openai.com/docs/guides/structured-outputs#supported-schemas
Thank you hanna! Yes this was the issue I had two tools with z.number().int().optional().nullable() I dropped the .nullable() and everything’s working again! Its strange that this doesn’t throw an error when connecting the app!
This is an interesting bug as the app would run in MCPJam totally fine running with gpt5.1 over api!
@hanna_grunt Thank you for sharing your solution. I just saw your response. It turns out the issue was in my tool description — the line break \n was causing problems. After a long debugging session, I realized the JS file wasn’t compiling correctly, but I was able to get it fixed.
This topic was automatically closed 2 days after the last reply. New replies are no longer allowed.
