ServiceNow MCP Server

Instructions

Implementation Reference

• src/servicenow_mcp/tools/change_tools.py:502-581 (handler)

  Main handler function that implements the tool logic: validates params, fetches change request details and associated tasks via ServiceNow REST API.

  def get_change_request_details(
      auth_manager: AuthManager,
      server_config: ServerConfig,
      params: Dict[str, Any],
  ) -> Dict[str, Any]:
      """
      Get details of a change request from ServiceNow.
  
      Args:
          auth_manager: The authentication manager.
          server_config: The server configuration.
          params: The parameters for getting change request details.
  
      Returns:
          The change request details.
      """
      # Unwrap and validate parameters
      result = _unwrap_and_validate_params(
          params, 
          GetChangeRequestDetailsParams,
          required_fields=["change_id"]
      )
      
      if not result["success"]:
          return result
      
      validated_params = result["params"]
      
      # Get the instance URL
      instance_url = _get_instance_url(auth_manager, server_config)
      if not instance_url:
          return {
              "success": False,
              "message": "Cannot find instance_url in either server_config or auth_manager",
          }
      
      # Get the headers
      headers = _get_headers(auth_manager, server_config)
      if not headers:
          return {
              "success": False,
              "message": "Cannot find get_headers method in either auth_manager or server_config",
          }
      
      # Make the API request
      url = f"{instance_url}/api/now/table/change_request/{validated_params.change_id}"
      
      params = {
          "sysparm_display_value": "true",
      }
      
      try:
          response = requests.get(url, headers=headers, params=params)
          response.raise_for_status()
          
          result = response.json()
          
          # Get tasks associated with this change request
          tasks_url = f"{instance_url}/api/now/table/change_task"
          tasks_params = {
              "sysparm_query": f"change_request={validated_params.change_id}",
              "sysparm_display_value": "true",
          }
          
          tasks_response = requests.get(tasks_url, headers=headers, params=tasks_params)
          tasks_response.raise_for_status()
          
          tasks_result = tasks_response.json()
          
          return {
              "success": True,
              "change_request": result["result"],
              "tasks": tasks_result["result"],
          }
      except requests.exceptions.RequestException as e:
          logger.error(f"Error getting change request details: {e}")
          return {
              "success": False,
              "message": f"Error getting change request details: {str(e)}",
          }

• src/servicenow_mcp/tools/change_tools.py:67-71 (schema)

  Pydantic BaseModel defining the input schema for the tool, requiring 'change_id'.

  class GetChangeRequestDetailsParams(BaseModel):
      """Parameters for getting change request details."""
  
      change_id: str = Field(..., description="Change request ID or sys_id")

• src/servicenow_mcp/utils/tool_utils.py:500-506 (registration)

  Tool registration in the central get_tool_definitions() function's dictionary, mapping name to (handler, schema, return_type, description, serialization).

  "get_change_request_details": (
      get_change_request_details_tool,
      GetChangeRequestDetailsParams,
      str,  # Expects JSON string
      "Get detailed information about a specific change request",
      "json",  # Tool returns list/dict
  ),