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```
Error: 400 Function tools with reasoning_effort are not supported for gpt-5.4-mini in /v1/chat/completions. Please use /v1/responses instead.
```
Do you have a solution (other than using different class of model)?

Hi there,
This is a known incompatibility with GPT-5.4-mini and function tools when reasoning_effort is set.

The quickest fix is to switch to GPT-4.1 or any other supported model, which supports both without issues.

Yes I know I can use an alt model like gpt 4.1
But is fixing the issue on your roadmap at all? Do you have a rough ETA?

We don't have an ETA on supporting the `/v1/responses` endpoint at this time, but it's something we're aware of.

We'll update our docs if anything changes on this front.