GIS MCP Server

Instructions

Implementation Reference

• src/gis_mcp/pyproj_functions.py:291-322 (handler)

  The core handler function for the 'get_utm_crs' tool, decorated with @gis_mcp.tool(). It uses pyproj to query the UTM CRS info for the given lon/lat coordinates and returns the CRS string representation.

  @gis_mcp.tool()
  def get_utm_crs(coordinates: List[float]) -> Dict[str, Any]:
      """Get UTM CRS for given coordinates."""
      try:
          import pyproj
          from pyproj.database import query_utm_crs_info
          lon, lat = coordinates
          crs_info_list = query_utm_crs_info(
              datum_name="WGS 84",  # Use "WGS 84" with space as per standard
              area_of_interest=pyproj.aoi.AreaOfInterest(
                  west_lon_degree=lon,
                  south_lat_degree=lat,
                  east_lon_degree=lon,
                  north_lat_degree=lat
              )
          )
          if not crs_info_list:
              raise ValueError("No UTM CRS found for the given coordinates")
          
          # Create CRS from CRSInfo and get its string representation
          crs_obj = pyproj.CRS.from_authority(crs_info_list[0].auth_name, crs_info_list[0].code)
          crs_str = crs_obj.to_string()
          
          return {
              "status": "success",
              "crs": crs_str,
              "message": "UTM CRS retrieved successfully"
          }
      except Exception as e:
          logger.error(f"Error getting UTM CRS: {str(e)}")
          raise ValueError(f"Failed to get UTM CRS: {str(e)}")

• src/gis_mcp/pyproj_functions.py:19-30 (registration)

  MCP resource endpoint that lists 'get_utm_crs' among the available CRS information operations, serving as a tool directory.

  @gis_mcp.resource("gis://crs/info")
  def get_crs_info_operations() -> Dict[str, List[str]]:
      """List available CRS information operations."""
      return {
          "operations": [
              "get_crs_info",
              "get_available_crs",
              "get_utm_zone",
              "get_utm_crs",
              "get_geocentric_crs"
          ]
      }