Caiyun Weather MCP Server

Hosted Server

Caiyun Weather provides a hosted Streamable HTTP MCP server, so you can use

the weather tools without installing or running this package locally.

{
  "url": "https://mcp-weather.caiyunapp.com/mcp",
  "headers": {
    "X-Caiyun-API-Key": "YOUR_CAIYUN_WEATHER_API_KEY"
  }
}

The outer configuration format depends on your MCP client. Before getting

started, register and apply for a Caiyun Weather API key,

then pass it in the `X-Caiyun-API-Key` request header.

Setup Instructions

Install uv first.

MacOS/Linux:

curl -LsSf https://astral.sh/uv/install.sh | sh

Windows:

powershell -ExecutionPolicy ByPass -c "irm https://astral.sh/uv/install.ps1 | iex"

Setup with Claude Desktop

# claude_desktop_config.json
# Can find location through:
# Hamburger Menu -> File -> Settings -> Developer -> Edit Config
{
  "mcpServers": {
    "caiyun-weather": {
      "command": "uvx",
      "args": ["mcp-caiyun-weather"],
      "env": {
        "CAIYUN_WEATHER_API_TOKEN": "YOUR_API_KEY_HERE"
      }
    }
  }
}

Ask Claude a question requiring weather

e.g. "What's the weather in Beijing Now?"

Local/Dev Setup Instructions

Setup with Claude Desktop

# claude_desktop_config.json
# Can find location through:
# Hamburger Menu -> File -> Settings -> Developer -> Edit Config
{
  "mcpServers": {
    "caiyun-weather": {
      "command": "uv",
      "args": [
        "--directory",
        "/ABSOLUTE/PATH/TO/PARENT/FOLDER/mcp-caiyun-weather",
        "run",
        "mcp-caiyun-weather"
      ],
      "env": {
        "CAIYUN_WEATHER_API_TOKEN": "YOUR_API_TOKEN_HERE"
      }
    }
  }
}

Debugging

Run:

npx @modelcontextprotocol/inspector \
      uv \
      --directory /ABSOLUTE/PATH/TO/PARENT/FOLDER/mcp-caiyun-weather \
      run \
      mcp-caiyun-weather

Available Tools

• `get_realtime_weather`: Get real-time weather data for a specific location
  • Parameters:
    • `lng`: The longitude of the location
    • `lat`: The latitude of the location
  • Returns detailed information including:
    • Temperature and apparent temperature
    • Sky condition
    • Humidity
    • Wind speed and direction
    • Precipitation intensity
    • Air quality metrics (PM2.5, PM10, O3, SO2, NO2, CO)
    • AQI (China and USA standards)
    • Life indices (UV and Comfort)

• `get_hourly_forecast`: Get an hourly weather forecast for a configurable number of hours
  • Parameters:
    • `lng`: The longitude of the location
    • `lat`: The latitude of the location
    • `hours`: The number of hours to return (`1`–`360`, defaults to `72`)
  • Returns hourly forecast including:
    • Temperature
    • Weather conditions
    • Rain probability
    • Precipitation intensity (mm/hr)
    • Wind speed and direction

• `get_weekly_forecast`: Get daily weather forecast for the next 7 days
  • Parameters:
    • `lng`: The longitude of the location
    • `lat`: The latitude of the location
  • Returns daily forecast including:
    • Temperature range (min/max)
    • Weather conditions
    • Rain probability

• `get_historical_weather`: Get historical weather data for the past 24 hours
  • Parameters:
    • `lng`: The longitude of the location
    • `lat`: The latitude of the location
  • Returns historical data including:
    • Temperature
    • Weather conditions

• `get_weather_alerts`: Get weather alerts for a specific location
  • Parameters:
    • `lng`: The longitude of the location
    • `lat`: The latitude of the location
  • Returns weather alerts including:
    • Alert title
    • Alert code
    • Alert status
    • Alert description

Note: All tools require a valid Caiyun Weather API token to be set in the environment variable `CAIYUN_WEATHER_API_TOKEN`.