Introduction

This is a tutorial application for setting a Server-Sent Events (SSE) Model Context Protocol (MCP) Server. This server returns weather information for a specified location.

This server demonstrates how to implement a simple MCP SSE server that can be integrated with AI agents.

Features

• SSE-based MCP server implementation

• Real-time weather data retrieval

• Support for current conditions and forecasts

• Easy integration with AI agents through MCP

Prerequisites

• Python 3.10 or later

• Node.js and NPM (for the MCP Inspector)

• Git (for version control)

Installation

1. Clone the repository:

   git clone [repository-url]
   cd mcp-weather-service

2. Run the setup script:

   scripts/setup.bat

   This will:

   • Create a Python virtual environment in .venv

   • Activate the virtual environment

   • Install all required dependencies

3. (Optional) Configure your IDE to use the Python interpreter from .venv

Running the Server

There are several ways to run the server:

Method 1: Direct Run (Preferred)

python src/mcp_weather_service/weather_server.py

Method 2: Using Uvicorn

uvicorn mcp_weather_service.weather_server:app --host 127.0.0.1 --port 3001

Method 3: Using Launch Script

scripts/launch.bat

Verifying the Server

1. Check if the server is running:

   • Open your browser and navigate to http://127.0.0.1:3001/sse

   • You should see a response like:

     event: endpoint
     data: /weather?session_id=f0c33285de5846d79a89f41212acfd75

2. Using the MCP Inspector:

   scripts/inspect.bat

   This launches the MCP Protocol Inspector, which allows you to:

   • Interact with the server directly

   • Test weather queries

   • Debug server responses

   • You MUST connect via http://127.0.0.1:3001/sse (use 127.0.0.1 instead of localhost especially on Windows!)

3. Using with a MCP Client There is a gradio MCP Client demo that can be used to interact with this server. See that projects' details to set it up The entry for config.json for THAT project is:

{
  "mcpServers": {
    "weather": {
      "type": "sse",
      "url": "http://127.0.0.1"
    }
  }
}

Available Tools

get_current_weather

Gets current weather and forecast for a specified location.

Input Schema:

{
  "location_name": {
    "type": "string",
    "description": "The location to get the weather for"
  }
}

Example Response:

{
  "currently": {
    "current_temperature": 72.5,
    "sky": "☀️",
    "feels_like": 74.2,
    "humidity": 65,
    "wind_speed": 8.5,
    "wind_direction": "NW↗️",
    "visibility": 10,
    "uv_index": 5,
    "description": "Clear skies",
    "forecasts": [
      {
        "date": "2024-12-05",
        "high_temperature": 75.8,
        "low_temperature": 62.4
      }
    ]
  }
}

Development

Virtual Environment

The project uses a Python virtual environment located in .venv. To activate it manually:

.venv\Scripts\activate  # Windows
source .venv/bin/activate  # Unix/MacOS

Adding Dependencies

1. Add new dependencies to pyproject.toml

2. Run scripts/install_deps.bat to install them

Troubleshooting

Common Issues

1. Server Won't Start

   • Verify Python version (3.10+)

   • Check if port 3001 is available

   • Ensure virtual environment is activated

2. MCP Inspector Connection Failed

   • Verify the server is running

   • Check the URL (should be http://127.0.0.1:3001/sse)

   • Ensure Node.js and NPM are installed

3. Weather Data Not Returning

   • Check internet connectivity

   • Verify location name format

License

MIT License - See LICENSE file for details

Contributing

1. Fork the repository

2. Create your feature branch

3. Commit your changes

4. Push to the branch

5. Create a new Pull Request