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400 Function tools with reasoning_effort are not supported for gpt-5.4-nano in /v1/chat/completions. Please use /v1/responses instead."

Seeing that error.... b3f57635-b9ff-4755-b03b-73e45bcb171d

^ that is the assistant ID - you can check the call i did there

Hi! I can help troubleshoot this quickly.

That error usually happens because GPT-5.4-nano doesn't support function tools with `reasoning_effort` on the `/v1/chat/completions` endpoint. You'll need to switch to the `/v1/responses` API or adjust the model/tool configuration.

If you'd like, send me the assistant setup or request payload and I'll pinpoint the exact issue.

<@631782520794644491>

Hey,

Could you please switch to another supported model and let me know if you're still experiencing the issue?

Kind regards,
Akash