GIS MCP Server

Instructions

Implementation Reference

• src/gis_mcp/rasterio_functions.py:37-84 (handler)

  The core handler function for the 'zonal_statistics' tool, decorated with @gis_mcp.tool(). It reads a vector file with geopandas, masks the raster using rasterio.mask for each polygon, computes specified statistics (mean, min, max, std) on masked data using numpy, and returns results per polygon.
  @gis_mcp.tool() def zonal_statistics(raster_path: str, vector_path: str, stats: list = None) -> Dict[str, Any]: """ Calculate statistics of raster values within polygons (zonal statistics). Args: raster_path: Path to the raster file. vector_path: Path to the vector file (polygons). stats: List of statistics to compute (e.g., ["mean", "min", "max", "std"]). Returns: Dictionary with status, message, and statistics per polygon. """ try: import rasterio import rasterio.mask import geopandas as gpd import numpy as np if stats is None: stats = ["mean", "min", "max", "std"] gdf = gpd.read_file(vector_path) with rasterio.open(raster_path) as src: results = [] for idx, row in gdf.iterrows(): geom = [row["geometry"]] out_image, out_transform = rasterio.mask.mask(src, geom, crop=True, filled=True) data = out_image[0] data = data[data != src.nodata] if src.nodata is not None else data stat_result = {"index": idx} if data.size == 0: for s in stats: stat_result[s] = None else: if "mean" in stats: stat_result["mean"] = float(np.mean(data)) if "min" in stats: stat_result["min"] = float(np.min(data)) if "max" in stats: stat_result["max"] = float(np.max(data)) if "std" in stats: stat_result["std"] = float(np.std(data)) results.append(stat_result) return { "status": "success", "message": "Zonal statistics computed successfully.", "results": results } except Exception as e: logger.error(f"Error in zonal_statistics: {str(e)}") return {"status": "error", "message": str(e)}
• src/gis_mcp/rasterio_functions.py:11-35 (registration)

  MCP resource handler that lists all available rasterio operations, including 'zonal_statistics', for tool discovery.
  @gis_mcp.resource("gis://operation/rasterio") def get_rasterio_operations() -> Dict[str, List[str]]: """List available rasterio operations.""" return { "operations": [ "metadata_raster", "get_raster_crs", "clip_raster_with_shapefile", "resample_raster", "reproject_raster", "weighted_band_sum", "concat_bands", "raster_algebra", "compute_ndvi", "raster_histogram", "tile_raster", "raster_band_statistics", "extract_band", "zonal_statistics", "reclassify_raster", "focal_statistics", "hillshade", "write_raster" ] }
• src/gis_mcp/rasterio_functions.py:38-47 (schema)

  Function signature with type annotations and docstring defining input parameters and return type for the zonal_statistics tool.
  def zonal_statistics(raster_path: str, vector_path: str, stats: list = None) -> Dict[str, Any]: """ Calculate statistics of raster values within polygons (zonal statistics). Args: raster_path: Path to the raster file. vector_path: Path to the vector file (polygons). stats: List of statistics to compute (e.g., ["mean", "min", "max", "std"]). Returns: Dictionary with status, message, and statistics per polygon. """