JMA Data MCP

Instructions

Implementation Reference

• jma_data_mcp/server.py:102-124 (handler)

  The handler function for the 'list_stations' MCP tool, decorated with @mcp.tool() for automatic registration. It implements pagination on top of get_all_stations().

  @mcp.tool()
  async def list_stations(
      limit: int = 100,
      offset: int = 0,
  ) -> dict:
      """List all AMeDAS stations (1286 stations) with pagination.
  
      Args:
          limit: Maximum number of stations to return (default: 100)
          offset: Number of stations to skip (default: 0)
  
      Returns:
          Paginated list of stations
      """
      all_stations = get_all_stations()
      paginated = all_stations[offset : offset + limit]
      return {
          "total": len(all_stations),
          "offset": offset,
          "limit": limit,
          "count": len(paginated),
          "stations": paginated,
      }

• jma_data_mcp/stations.py:88-92 (helper)

  Helper function that loads the full list of AMeDAS stations from the local JSON data file and returns them as a list.

  def get_all_stations() -> list[dict]:
      """Get all stations."""
      stations = load_stations()
      return list(stations.values())