Clients that read environment variables can use
OPENAI_BASE_URL and OPENAI_API_KEY.
The API rejects fields it does not support with 400 invalid_request. It does not ignore them. Check that your client does not add the fields listed as not supported below.
Endpoints
Request fields
The API also accepts
top_k, min_p and repetition_penalty for models that support them — see Chat completions.