GIS MCP Server

Instructions

Implementation Reference

• src/gis_mcp/shapely_functions.py:512-535 (handler)

  The handler function for the 'nearest_point_on_geometry' tool. It takes two WKT geometry strings, uses Shapely's nearest_points to find the closest point on the second geometry to the first, and returns the result as WKT or error.

  @gis_mcp.tool()
  def nearest_point_on_geometry(geometry1: str, geometry2: str) -> Dict[str, Any]:
      """
      Find the nearest point on geometry2 to geometry1 using shapely.ops.nearest_points.
      Args:
          geometry1: WKT string of the first geometry (e.g., a point).
          geometry2: WKT string of the second geometry.
      Returns:
          Dictionary with status, message, and the nearest point as WKT.
      """
      try:
          from shapely import wkt
          from shapely.ops import nearest_points
          geom1 = wkt.loads(geometry1)
          geom2 = wkt.loads(geometry2)
          p1, p2 = nearest_points(geom1, geom2)
          return {
              "status": "success",
              "nearest_point": p2.wkt,
              "message": "Nearest point found successfully"
          }
      except Exception as e:
          logger.error(f"Error in nearest_point_on_geometry: {str(e)}")
          return {"status": "error", "message": str(e)}

• src/gis_mcp/shapely_functions.py:82-93 (registration)

  Resource handler that lists 'nearest_point_on_geometry' among the available Shapely utility operations, effectively registering or documenting its availability.

  @gis_mcp.resource("gis://operations/shapely_util")
  def get_shapely_util_operations() -> Dict[str, List[str]]:
      """List available Shapely utility/advanced operations."""
      return {
          "operations": [
              "snap_geometry",
              "nearest_point_on_geometry",
              "normalize_geometry",
              "geometry_to_geojson",
              "geojson_to_geometry"
          ]
      }