> ## Documentation Index
> Fetch the complete documentation index at: https://agno-v2.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Tool Use

> Mistral tool use example with a custom function tool.

```python tool_use.py theme={null}
"""Mistral tool use example with a custom function tool."""

import asyncio
import json

from agno.agent import Agent
from agno.models.mistral import MistralChat
from agno.tools import tool

# ---------------------------------------------------------------------------
# Define a tool
# ---------------------------------------------------------------------------


@tool
def get_weather(city: str) -> str:
    """Get the current weather for a city.

    Args:
        city: The city name to get weather for.
    """
    weather_data = {
        "Paris": {"temp": 18, "condition": "cloudy", "humidity": 65},
        "London": {"temp": 14, "condition": "rainy", "humidity": 80},
        "Tokyo": {"temp": 22, "condition": "sunny", "humidity": 50},
        "New York": {"temp": 20, "condition": "partly cloudy", "humidity": 55},
    }
    data = weather_data.get(city, {"temp": 20, "condition": "unknown", "humidity": 50})
    return json.dumps(data)


# ---------------------------------------------------------------------------
# Create Agent
# ---------------------------------------------------------------------------

agent = Agent(
    model=MistralChat(id="mistral-large-latest"),
    tools=[get_weather],
    markdown=True,
)

# ---------------------------------------------------------------------------
# Run Agent
# ---------------------------------------------------------------------------
if __name__ == "__main__":
    # --- Sync ---
    agent.print_response("What is the weather in Paris and Tokyo?")

    # --- Async ---
    asyncio.run(agent.aprint_response("What is the weather in London and New York?"))
```

## Run the Example

<Snippet file="create-venv-step.mdx" />

**1. Install dependencies**

```bash theme={null}
uv pip install -U agno mistralai
```

**2. Export your Mistral API key**

```bash Mac/Linux theme={null}
export MISTRAL_API_KEY="your_mistral_api_key_here"
```

```bash Windows theme={null}
$Env:MISTRAL_API_KEY="your_mistral_api_key_here"
```

**3. Run the example**

Save the code above as `tool_use.py`, then run:

```bash theme={null}
python tool_use.py
```

Full source: [cookbook/90\_models/mistral/tool\_use.py](https://github.com/agno-agi/agno/blob/v3.0.4/cookbook/90_models/mistral/tool_use.py)


This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.