mcp_app_server

MCP Weather App Server

This project is a simple Model Context Protocol (MCP) server that provides real-time weather information for any city using the OpenWeather API. It is built with Python and leverages the FastMCP framework for easy tool integration and API serving.

Features

• Fetches current weather data for any city worldwide
• Returns temperature, humidity, weather description, wind speed/direction, cloudiness, and more
• Uses OpenWeather's geocoding and weather APIs
• Designed as an MCP tool for easy integration with AI agents and other MCP clients

Requirements

• Python 3.8+
• OpenWeather API Key
• Internet connection

Installation

1. Clone the repository:

   git clone <your-repo-url>
   cd mcp_app_server
   

2. Install dependencies:
   If using pip:

   pip install -r requirements.txt
   

   Or, if using pyproject.toml (with UV):

   uv install
   

   Ensure you have uv installed. If not, you can install it via pip:

3. Set up environment variables:

   • Create a .env file in the project root directory and add your OpenWeather API key:

     echo "OPENWEATHER_API_KEY=your_openweather_api_key_here" > .env
     

   • Create a .env file in the project root:

   OPENWEATHER_API_KEY=your_openweather_api_key_here
   

Usage

Run the server with:

python main.py

The server will start and expose the MCP tool for weather queries.

Example Tool Usage

The main tool is get_weather(city: str) -> dict, which fetches weather data for the specified city.

Example Request

from mcp_weather import get_weather
result = get_weather("London")
print(result)

Example Response

{
  "city": "London",
  "temperature": 18.5,
  "humidity": 65,
  "description": "light rain",
  "icon": "10d",
  "wind_speed": 4.1,
  "wind_direction": 80,
  "cloudiness": 90,
  "timestamp": 1719324000,
  "timezone": 3600,
  "country": "GB"
}

Project Structure

mcp_app_server/
├── LICENSE
├── main.py            # Entry point to run the MCP server
├── Notes.txt
├── pyproject.toml     # Project metadata and dependencies
├── README.md
├── uv.lock
└── src/
    ├── mcp_weather.py # Weather tool implementation

Environment Variables

• OPENWEATHER_API_KEY: Your API key from OpenWeather. Required for the server to fetch weather data.

Error Handling

• If the API key is missing or invalid, the server will raise an error.
• If the city is not found, a descriptive error is returned.
• Handles unexpected API response formats gracefully.

Extending

• Add more MCP tools by defining new functions with the @mcp.tool() decorator in src/mcp_weather.py or new modules.
• Integrate with other MCP-compatible agents or clients as needed.

📝 License

This project is MIT licensed.

Acknowledgments

• OpenWeather API
• FastMCP Framework