I am getting this error as well and tried the hack proposed in this GitHub issue but then it just returned a 500 rather than a 400:
litellm.llms.openai.common_utils.OpenAIError: Error code: 500 - {'error': {'message': 'The inference server returned an error.', 'type': 'unknown', 'code': 500}}
I’m using OpenAI clients for other agents which are performing as expected, so it’s not a matter of neglecting an OpenAI API key or the like, and the same code worked in earlier versions of Python/CrewAI. I’m currently using Python 3.11.11 due to issues with ChromaDB and 3.12.