What happened?

When using the gpt-5-chat-latest model, an intelligence model, it throws a LiteLLM error:

litellm.UnsupportedParamsError: gpt-5 models don't support temperature=0.3. Only temperature=1 is supported. To drop unsupported params, set litellm.drop_params = True.

However, this GPT-5 model should accept the 'temperature' parameter because it is an intelligence model, not a reasoning model.

Here is a reproducible example:

import os
import openai

client = openai.OpenAI(
    api_key=os.getenv("litellm_api_key"),
    base_ur=os.getenv("litellm_url")
)

client.chat.completions.create(
    model="openai/gpt-5-chat-latest",
    messages=[
        {
            "role": "user",
            "content": "What is the capital of México?",
        },
    ],
    temperature=0.3,
)

Relevant log output

litellm.UnsupportedParamsError: gpt-5 models don't support temperature=0.3. Only temperature=1 is supported. To drop unsupported params set `litellm.drop_params = True`

Are you a ML Ops Team?

No

What LiteLLM version are you on ?

v1.75.6

Twitter / LinkedIn details

No response