[BUG MODEL]: Magistral models ignore `tool_choice="required"` and return text instead of tool calls

[bilelomrani1]

Models

magistral-medium-2509
magistral-medium-latest
magistral-small-2509
magistral-small-latest

Request Payload

import asyncio
import os
from mistralai import Mistral

TOOL = {
    "type": "function",
    "function": {
        "name": "get_weather",
        "description": "Get the current weather for a city",
        "parameters": {
            "type": "object",
            "properties": {"city": {"type": "string", "description": "City name"}},
            "required": ["city"],
        },
    },
}

async def main():
    client = Mistral(api_key=os.environ["MISTRAL_API_KEY"])
    for model in [
        "magistral-medium-2509",
        "magistral-medium-latest",
        "magistral-small-2509",
        "magistral-small-latest",
    ]:
        resp = await client.chat.complete_async(
            model=model,
            messages=[{"role": "user", "content": "Say hello."}],
            tools=[TOOL],
            tool_choice="required",
            max_tokens=256,
            temperature=0,
        )
        choice = resp.choices[0]
        print(f"{model}: finish_reason={choice.finish_reason}, tool_calls={choice.message.tool_calls}")


asyncio.run(main())

Output

All four magistral models return a text response with no tool calls, despite tool_choice="required":

magistral-medium-2509:   finish_reason=length, tool_calls=None
magistral-medium-latest: finish_reason=length, tool_calls=None
magistral-small-2509:    finish_reason=length, tool_calls=None
magistral-small-latest:  finish_reason=length, tool_calls=None

The response content is a plain text greeting (e.g. "Hello! How can I assist you today?") with no tool invocation.

Expected Behavior

When tool_choice="required" is set, the model should always produce at least one tool call, regardless of the prompt content. This is the documented behavior and works correctly with other Mistral model families (e.g. mistral-large-latest, mistral-small-latest, codestral-latest).

Additional Context

No response

Suggested Solutions

No response

[louis-sanna-dev]

@bilelomrani1 should be fixed in 2.0.3 🙏

EDIT: closed the wrong issue, I meant to reply to #418