QGISMCP

Instructions

Implementation Reference

• qgis_mcp_plugin/qgis_mcp_plugin.py:221-240 (handler)

  Core handler function in the QGIS plugin that executes the provided PyQGIS code using exec() in a safe namespace.

  def execute_code(self, code, **kwargs):
      """Execute arbitrary PyQGIS code"""
      try:
          # Create a local namespace for execution
          namespace = {
              "qgis": Qgis,
              "QgsProject": QgsProject,
              "iface": self.iface,
              "QgsApplication": QgsApplication,
              "QgsVectorLayer": QgsVectorLayer,
              "QgsRasterLayer": QgsRasterLayer,
              "QgsCoordinateReferenceSystem": QgsCoordinateReferenceSystem
          }
          
          # Execute the code
          exec(code, namespace)
          return {"executed": True}
      except Exception as e:
          raise Exception(f"Code execution error: {str(e)}")

• src/qgis_mcp/qgis_mcp_server.py:256-262 (handler)

  MCP tool handler that proxies the execute_code command to the QGIS plugin server via socket.

  @mcp.tool()
  def execute_code(ctx: Context, code: str) -> str:
      """Execute arbitrary PyQGIS code provided as a string."""
      qgis = get_qgis_connection()
      result = qgis.send_command("execute_code", {"code": code})
      return json.dumps(result, indent=2)

• qgis_mcp_plugin/qgis_mcp_plugin.py:133-149 (registration)

  Registration of command handlers in the QGIS plugin server, including execute_code.

  handlers = {
      "ping": self.ping,
      "get_qgis_info": self.get_qgis_info,
      "load_project": self.load_project,
      "get_project_info": self.get_project_info,
      "execute_code": self.execute_code,
      "add_vector_layer": self.add_vector_layer,
      "add_raster_layer": self.add_raster_layer,
      "get_layers": self.get_layers,
      "remove_layer": self.remove_layer,
      "zoom_to_layer": self.zoom_to_layer,
      "get_layer_features": self.get_layer_features,
      "execute_processing": self.execute_processing,
      "save_project": self.save_project,
      "render_map": self.render_map,
      "create_new_project": self.create_new_project,
  }

• src/qgis_mcp/qgis_mcp_server.py:256-262 (registration)

  MCP tool registration decorator for execute_code.

  @mcp.tool()
  def execute_code(ctx: Context, code: str) -> str:
      """Execute arbitrary PyQGIS code provided as a string."""
      qgis = get_qgis_connection()
      result = qgis.send_command("execute_code", {"code": code})
      return json.dumps(result, indent=2)

• src/qgis_mcp/qgis_socket_client.py:83-85 (helper)

  Helper method in socket client wrapper for sending execute_code command.

  def execute_code(self, code):
      """Execute arbitrary PyQGIS code"""
      return self.send_command("execute_code", {"code": code})