# Weather Tool Setup

The weather tool uses the OpenWeatherMap API to get real-time weather information.

## Setup

1. **Get API Key** (Free tier available):
   - Visit https://openweathermap.org/api
   - Sign up for a free account
   - Get your API key from the dashboard

2. **Set Environment Variable**:
   ```bash
   export OPENWEATHERMAP_API_KEY="your-api-key-here"
   ```

3. **Or add to `.env` file** (if using python-dotenv):
   ```
   OPENWEATHERMAP_API_KEY=your-api-key-here
   ```

## Rate Limits

- **Free tier**: 60 requests per hour
- The tool automatically enforces rate limiting
- Requests are tracked per hour

## Usage

The tool accepts:
- **Location**: City name (e.g., "San Francisco, CA" or "London, UK")
- **Units**: "metric" (Celsius), "imperial" (Fahrenheit), or "kelvin" (default: metric)

## Example

```python
# Via MCP
{
  "method": "tools/call",
  "params": {
    "name": "weather",
    "arguments": {
      "location": "New York, NY",
      "units": "metric"
    }
  }
}
```

## Error Handling

The tool handles:
- Missing API key (clear error message)
- Invalid location (404 error)
- Rate limit exceeded (429 error)
- Network errors (timeout, connection errors)
- Invalid API key (401 error)

## Privacy Note

Weather is an exception to the "no external APIs" policy as documented in the privacy policy. This is the only external API used by the system.