mcp-weather-server 0.4.1

An MCP server for weather information

Weather MCP Server

A Model Context Protocol (MCP) server that provides weather information using the Open-Meteo API. This server supports multiple transport modes: standard stdio, HTTP Server-Sent Events (SSE), and the new Streamable HTTP protocol for web-based integration.

Features

• Get current weather information for a specified city
• Get weather data for a date range
• Get current date/time in any timezone
• Convert time between timezones
• Get timezone information
• Multiple transport modes:
  • stdio - Standard MCP for desktop clients (Claude Desktop, etc.)
  • SSE - Server-Sent Events for web applications
  • streamable-http - Modern MCP Streamable HTTP protocol with stateful/stateless options
• RESTful API endpoints via Starlette integration

Installation

Installing via Smithery

To install Weather MCP Server automatically via Smithery:

npx -y @smithery/cli install @isdaniel/mcp_weather_server

Standard Installation (for MCP clients like Claude Desktop)

This package can be installed using pip:

pip install mcp_weather_server

Manual Configuration for MCP Clients

This server is designed to be installed manually by adding its configuration to the cline_mcp_settings.json file.

1. Add the following entry to the mcpServers object in your cline_mcp_settings.json file:

{
  "mcpServers": {
    "weather": {
      "command": "python",
      "args": [
        "-m",
        "mcp_weather_server"
      ],
      "disabled": false,
      "autoApprove": []
    }
  }
}

2. Save the cline_mcp_settings.json file.

HTTP Server Installation (for web applications)

For HTTP SSE or Streamable HTTP support, you'll need additional dependencies:

pip install mcp_weather_server starlette uvicorn

Server Modes

This MCP server supports stdio, SSE, and streamable-http modes in a single unified server:

Mode Comparison

Feature	stdio	SSE	streamable-http
Use Case	Desktop MCP clients	Web applications (legacy)	Web applications (modern)
Protocol	Standard I/O streams	Server-Sent Events	MCP Streamable HTTP
Session Management	N/A	Stateful	Stateful or Stateless
Endpoints	N/A	/sse, /messages/	/mcp (single)
Best For	Claude Desktop, Cline	Browser-based apps	Modern web apps, APIs
State Options	N/A	Stateful only	Stateful or Stateless

1. Standard MCP Mode (Default)

The standard mode communicates via stdio and is compatible with MCP clients like Claude Desktop.

# Default mode (stdio)
python -m mcp_weather_server

# Explicitly specify stdio mode
python -m mcp_weather_server.server --mode stdio

2. HTTP SSE Mode (Web Applications)

The SSE mode runs an HTTP server that provides MCP functionality via Server-Sent Events, making it accessible to web applications.

# Start SSE server on default host/port (0.0.0.0:8080)
python -m mcp_weather_server --mode sse

# Specify custom host and port
python -m mcp_weather_server --mode sse --host localhost --port 3000

# Enable debug mode
python -m mcp_weather_server --mode sse --debug

SSE Endpoints:

• GET /sse - SSE endpoint for MCP communication
• POST /messages/ - Message endpoint for sending MCP requests

3. Streamable HTTP Mode (Modern MCP Protocol)

The streamable-http mode implements the new MCP Streamable HTTP protocol with a single /mcp endpoint. This mode supports both stateful (default) and stateless operations.

# Start streamable HTTP server on default host/port (0.0.0.0:8080)
python -m mcp_weather_server --mode streamable-http

# Specify custom host and port
python -m mcp_weather_server --mode streamable-http --host localhost --port 3000

# Enable stateless mode (creates fresh transport per request, no session tracking)
python -m mcp_weather_server --mode streamable-http --stateless

# Enable debug mode
python -m mcp_weather_server --mode streamable-http --debug

Streamable HTTP Features:

• Stateful mode (default): Maintains session state across requests using session IDs
• Stateless mode: Creates fresh transport per request with no session tracking
• Single endpoint: All MCP communication happens through /mcp
• Modern protocol: Implements the latest MCP Streamable HTTP specification

Streamable HTTP Endpoint:

• POST /mcp - Single endpoint for all MCP communication (initialize, tools/list, tools/call, etc.)

Command Line Options:

--mode {stdio,sse,streamable-http}  Server mode: stdio (default), sse, or streamable-http
--host HOST                          Host to bind to (HTTP modes only, default: 0.0.0.0)
--port PORT                          Port to listen on (HTTP modes only, default: 8080)
--stateless                          Run in stateless mode (streamable-http only)
--debug                              Enable debug mode

Example SSE Usage:

// Connect to SSE endpoint
const eventSource = new EventSource('http://localhost:8080/sse');

// Send MCP tool request
fetch('http://localhost:8080/messages/', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({
    type: 'tool_call',
    tool: 'get_weather',
    arguments: { city: 'Tokyo' }
  })
});

Example Streamable HTTP Usage:

// Initialize session and call tool using Streamable HTTP protocol
async function callWeatherTool() {
  const response = await fetch('http://localhost:8080/mcp', {
    method: 'POST',
    headers: {
      'Content-Type': 'application/json'
    },
    body: JSON.stringify({
      jsonrpc: '2.0',
      method: 'tools/call',
      params: {
        name: 'get_current_weather',
        arguments: { city: 'Tokyo' }
      },
      id: 1
    })
  });

  const result = await response.json();
  console.log(result);
}

Configuration

This server does not require an API key. It uses the Open-Meteo API, which is free and open-source.

Usage

This server provides several tools for weather and time-related operations:

Available Tools

1. get_current_weather - Get current weather for a city
2. get_weather_by_datetime_range - Get weather data for a date range
3. get_current_datetime - Get current time in any timezone
4. get_timezone_info - Get timezone information
5. convert_time - Convert time between timezones

Tool Details

get_current_weather

Retrieves the current weather information for a given city.

Parameters:

• city (string, required): The name of the city (English names only)

Returns: JSON formatted weather data with current temperature and conditions

Example:

{
  "city": "Taipei",
  "weather": "Partly cloudy",
  "temperature_celsius": 25
}

get_weather_by_datetime_range

Retrieves weather information for a specified city between start and end dates.

Parameters:

• city (string, required): The name of the city (English names only)
• start_date (string, required): Start date in format YYYY-MM-DD (ISO 8601)
• end_date (string, required): End date in format YYYY-MM-DD (ISO 8601)

Returns: JSON array with daily weather summaries

Example:

[
  {
    "date": "2024-01-01",
    "day_of_week": "Monday",
    "city": "London",
    "weather": "Light rain",
    "temperature_celsius": 8
  }
]

get_current_datetime

Retrieves the current time in a specified timezone.

Parameters:

• timezone_name (string, required): IANA timezone name (e.g., 'America/New_York', 'Europe/London'). Use UTC if no timezone provided.

Returns: Current date and time in the specified timezone

Example:

{
  "timezone": "America/New_York",
  "current_time": "2024-01-15T14:30:00-05:00",
  "utc_time": "2024-01-15T19:30:00Z"
}

get_timezone_info

Get information about a specific timezone.

Parameters:

• timezone_name (string, required): IANA timezone name

Returns: Timezone details including offset and DST information

convert_time

Convert time from one timezone to another.

Parameters:

• time_str (string, required): Time to convert (ISO format)
• from_timezone (string, required): Source timezone
• to_timezone (string, required): Target timezone

Returns: Converted time in target timezone

MCP Client Usage Examples

Using with Claude Desktop or MCP Clients

<use_mcp_tool>
<server_name>weather</server_name>
<tool_name>get_current_weather</tool_name>
<arguments>
{
  "city": "Tokyo"
}
</arguments>
</use_mcp_tool>

<use_mcp_tool>
<server_name>weather</server_name>
<tool_name>get_weather_by_datetime_range</tool_name>
<arguments>
{
  "city": "Paris",
  "start_date": "2024-01-01",
  "end_date": "2024-01-07"
}
</arguments>
</use_mcp_tool>

<use_mcp_tool>
<server_name>weather</server_name>
<tool_name>get_current_datetime</tool_name>
<arguments>
{
  "timezone_name": "Europe/Paris"
}
</arguments>
</use_mcp_tool>

Web Integration (SSE Mode)

When running in SSE mode, you can integrate the weather server with web applications:

HTML/JavaScript Example

<!DOCTYPE html>
<html>
<head>
    <title>Weather MCP Client</title>
</head>
<body>
    <div id="weather-data"></div>
    <script>
        // Connect to SSE endpoint
        const eventSource = new EventSource('http://localhost:8080/sse');

        eventSource.onmessage = function(event) {
            const data = JSON.parse(event.data);
            document.getElementById('weather-data').innerHTML = JSON.stringify(data, null, 2);
        };

        // Function to get weather
        async function getWeather(city) {
            const response = await fetch('http://localhost:8080/messages/', {
                method: 'POST',
                headers: { 'Content-Type': 'application/json' },
                body: JSON.stringify({
                    jsonrpc: '2.0',
                    method: 'tools/call',
                    params: {
                        name: 'get_current_weather',
                        arguments: { city: city }
                    },
                    id: 1
                })
            });
        }

        // Example: Get weather for Tokyo
        getWeather('Tokyo');
    </script>
</body>
</html>

Docker Deployment

The project includes Docker configurations for easy deployment:

SSE Mode Docker

# Build
docker build -t mcp-weather-server:sse .

# Run (port will be read from PORT env var, defaults to 8081)
docker run -p 8081:8081 mcp-weather-server:sse

# Run with custom port
docker run -p 8080:8080 -e PORT=8080 mcp-weather-server:sse

Streamable HTTP Mode Docker

# Build using streamable-http Dockerfile
docker build -f Dockerfile.streamable-http -t mcp-weather-server:streamable-http .

# Run in stateful mode
docker run -p 8080:8080 mcp-weather-server:streamable-http

# Run in stateless mode
docker run -p 8080:8080 -e STATELESS=true mcp-weather-server:streamable-http

Development

Project Structure

mcp_weather_server/
├── src/
│   └── mcp_weather_server/
│       ├── __init__.py
│       ├── __main__.py          # Main MCP server entry point
│       ├── server.py            # Unified server (stdio, SSE, streamable-http)
│       ├── utils.py             # Utility functions
│       └── tools/               # Tool implementations
│           ├── __init__.py
│           ├── toolhandler.py   # Base tool handler
│           ├── tools_weather.py # Weather-related tools
│           ├── tools_time.py    # Time-related tools
│           └── weather_service.py # Weather API service
├── tests/
├── Dockerfile                   # Docker configuration for SSE mode
├── Dockerfile.streamable-http   # Docker configuration for streamable-http mode
├── pyproject.toml
├── requirements.txt
└── README.md

Running for Development

Standard MCP Mode (stdio)

# From project root
python -m mcp_weather_server

# Or with PYTHONPATH
export PYTHONPATH="/path/to/mcp_weather_server/src"
python -m mcp_weather_server

SSE Server Mode

# From project root
python -m mcp_weather_server --mode sse --host 0.0.0.0 --port 8080

# With custom host/port
python -m mcp_weather_server --mode sse --host localhost --port 3000

Streamable HTTP Mode

# Stateful mode (default)
python -m mcp_weather_server --mode streamable-http --host 0.0.0.0 --port 8080

# With debug logging
python -m mcp_weather_server --mode streamable-http --debug

Adding New Tools

To add new weather or time-related tools:

1. Create a new tool handler in the appropriate file under tools/
2. Inherit from the ToolHandler base class
3. Implement the required methods (get_name, get_description, call)
4. Register the tool in server.py

Dependencies

Core Dependencies

• mcp>=1.0.0 - Model Context Protocol implementation
• httpx>=0.28.1 - HTTP client for API requests
• python-dateutil>=2.8.2 - Date/time parsing utilities

SSE Server Dependencies

• starlette - ASGI web framework
• uvicorn - ASGI server

Development Dependencies

• pytest - Testing framework

API Data Source

This server uses the Open-Meteo API, which is:

• Free and open-source
• No API key required
• Provides accurate weather forecasts
• Supports global locations
• Historical and current weather data

Troubleshooting

Common Issues

1. City not found

• Ensure city names are in English
• Try using the full city name or include country (e.g., "Paris, France")
• Check spelling of city names

2. HTTP Server not accessible (SSE or Streamable HTTP)

• Verify the server is running with the correct mode:
  • SSE: python -m mcp_weather_server --mode sse
  • Streamable HTTP: python -m mcp_weather_server --mode streamable-http
• Check firewall settings for the specified port
• Ensure all dependencies are installed: pip install starlette uvicorn
• Verify the correct endpoint:
  • SSE: http://localhost:8080/sse and http://localhost:8080/messages/
  • Streamable HTTP: http://localhost:8080/mcp

3. MCP Client connection issues

• Verify Python path in MCP client configuration
• Check that mcp_weather_server package is installed
• Ensure Python environment has required dependencies

4. Date format errors

• Use ISO 8601 format for dates: YYYY-MM-DD
• Ensure start_date is before end_date
• Check that dates are not too far in the future

Error Responses

The server returns structured error messages:

{
  "error": "Could not retrieve coordinates for InvalidCity."
}

Changelog

Latest Version

• Added Streamable HTTP protocol support - New streamable-http mode implementing the modern MCP Streamable HTTP specification
  • Stateful mode (default) with session management
  • Stateless mode for independent requests
  • Single /mcp endpoint for all MCP operations
• Added unified server architecture supporting stdio, SSE, and streamable-http in one codebase
• Added Docker configuration for streamable-http deployment
• Enhanced command-line interface with --stateless flag
• Improved CORS configuration for web integration

v0.2.1

• Added HTTP SSE (Server-Sent Events) support
• Added timezone conversion tools
• Enhanced weather data formatting
• Improved error handling
• Added comprehensive documentation

Previous Versions

• v0.2.0: Added date range weather queries
• v0.1.0: Initial release with basic weather functionality