Weather MCP Server

A Model Context Protocol (MCP) server that provides weather information, web search capabilities, and basic math operations using FastMCP.

Features

🌤️ Weather Tools

• get_alerts: Get weather alerts for any US state

• get_forecast: Get detailed weather forecast for any location (latitude/longitude)

🔍 Search Tools

• brave_search: Search the web using Brave Search API

• add_numbers: Add two numbers together

💡 Prompts

• suggest_events: Get comprehensive weather data and event suggestions for a location

Related MCP server: mcp-weather-api

Prerequisites

• Python 3.11 or higher

• uv package manager

• Brave Search API key (free from Brave Search API)

Installation

1. Clone and navigate to the project:

   cd /opt/projects/mcp-hack/weather

2. Install dependencies:

   uv sync

Configuration

The server uses a hardcoded Brave Search API key. If you want to use your own API key, you can:

1. Get a free API key from Brave Search API

2. Update the BRAVE_API_KEY constant in weather.py

Running the Server

Method 1: Direct Python execution

uv run python weather.py

Method 2: Using the main module

uv run python main.py

Method 3: Using uv with module execution

uv run -m weather

Usage Examples

Once the server is running, you can use the following tools:

Weather Tools

# Get weather alerts for California
get_alerts("CA")

# Get forecast for San Francisco (37.7749, -122.4194)
get_forecast(37.7749, -122.4194)

Search Tool

# Search the web with default 3 results
brave_search("python programming tutorials")

# Search with custom result count
brave_search("weather forecast San Francisco", 5)

Math Tool

# Add two numbers
add_numbers(15.5, 24.3)

Prompts

# Get weather-based event suggestions
suggest_events("San Francisco")
# or with coordinates
suggest_events("37.7749,-122.4194")

API Integration

This server integrates with:

• National Weather Service API: For weather data and alerts

• Brave Search API: For web search functionality

• FastMCP: For MCP server implementation

• LangChain Community: For Brave Search tool integration

Development

Project Structure

weather/
├── weather.py          # Main MCP server with all tools
├── main.py            # Alternative entry point
├── pyproject.toml     # Project dependencies
├── uv.lock           # Dependency lock file
└── README.md         # This file

Adding New Tools

To add new tools, follow the FastMCP pattern:

@mcp.tool()
async def your_tool_name(param1: str, param2: int = 10) -> str:
    """Tool description.
    
    Args:
        param1: Description of parameter 1
        param2: Description of parameter 2 (default: 10)
    """
    # Your tool logic here
    return "Tool result"

Troubleshooting

Common Issues

1. "BRAVE_SEARCH_API_KEY environment variable not set"

   • The API key is hardcoded in the server, but if you see this error, check that BRAVE_API_KEY is properly set in weather.py

2. Weather API errors

   • Ensure you're using valid US state codes (2 letters) for alerts

   • Verify latitude/longitude coordinates are valid for forecasts

3. Import errors

   • Run uv sync to ensure all dependencies are installed

   • Make sure you're using Python 3.11 or higher

Dependencies

Key dependencies include:

• fastmcp: MCP server framework

• httpx: HTTP client for API requests

• langchain-community: Brave Search integration

• langchain-core: Core LangChain functionality

License

This project is part of the MCP hack and is provided as-is for educational and development purposes.