ServiceNow MCP Server

Instructions

Implementation Reference

• src/servicenow_mcp/tools/epic_tools.py:243-327 (handler)

  The main handler function that implements the logic for the 'update_epic' tool. It validates input parameters using UpdateEpicParams, constructs the API request to update the epic in ServiceNow's rm_epic table, and returns the result.
  def update_epic( auth_manager: AuthManager, server_config: ServerConfig, params: Dict[str, Any], ) -> Dict[str, Any]: """ Update an existing epic in ServiceNow. Args: auth_manager: The authentication manager. server_config: The server configuration. params: The parameters for updating the epic. Returns: The updated epic. """ # Unwrap and validate parameters result = _unwrap_and_validate_params( params, UpdateEpicParams, required_fields=["epic_id"] ) if not result["success"]: return result validated_params = result["params"] # Prepare the request data data = {} # Add optional fields if provided if validated_params.short_description: data["short_description"] = validated_params.short_description if validated_params.description: data["description"] = validated_params.description if validated_params.priority: data["priority"] = validated_params.priority if validated_params.assignment_group: data["assignment_group"] = validated_params.assignment_group if validated_params.assigned_to: data["assigned_to"] = validated_params.assigned_to if validated_params.work_notes: data["work_notes"] = validated_params.work_notes # 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", } # Add Content-Type header headers["Content-Type"] = "application/json" # Make the API request url = f"{instance_url}/api/now/table/rm_epic/{validated_params.epic_id}" try: response = requests.put(url, json=data, headers=headers) response.raise_for_status() result = response.json() return { "success": True, "message": "Epic updated successfully", "epic": result["result"], } except requests.exceptions.RequestException as e: logger.error(f"Error updating epic: {e}") return { "success": False, "message": f"Error updating epic: {str(e)}", }
• src/servicenow_mcp/tools/epic_tools.py:33-44 (schema)

  Pydantic BaseModel defining the input schema/parameters for the update_epic tool, including required epic_id and optional fields for updating the epic.
  class UpdateEpicParams(BaseModel): """Parameters for updating an epic.""" epic_id: str = Field(..., description="Epic ID or sys_id") short_description: Optional[str] = Field(None, description="Short description of the epic") description: Optional[str] = Field(None, description="Detailed description of the epic") priority: Optional[str] = Field(None, description="Priority of epic (1 is Critical, 2 is High, 3 is Moderate, 4 is Low, 5 is Planning)") state: Optional[str] = Field(None, description="State of story (-6 is Draft,1 is Ready,2 is Work in progress, 3 is Complete, 4 is Cancelled)") assignment_group: Optional[str] = Field(None, description="Group assigned to the epic") assigned_to: Optional[str] = Field(None, description="User assigned to the epic") work_notes: Optional[str] = Field(None, description="Work notes to add to the epic. Used for adding notes and comments to an epic")
• src/servicenow_mcp/utils/tool_utils.py:887-893 (registration)

  Registration of the 'update_epic' tool in the central tool_definitions dictionary used by the MCP server. Maps the tool name to its handler function (update_epic_tool), input schema (UpdateEpicParams), return type, description, and serialization method.
  "update_epic": ( update_epic_tool, UpdateEpicParams, str, "Update an existing epic in ServiceNow", "str", ),
• src/servicenow_mcp/tools/__init__.py:100-104 (registration)

  Import of the update_epic handler function into the tools package __init__.py, making it available for further imports and the __all__ export list.
  from servicenow_mcp.tools.epic_tools import ( create_epic, update_epic, list_epics, )
• src/servicenow_mcp/tools/epic_tools.py:56-108 (helper)

  Helper function used by update_epic (and other tools) to unwrap, validate parameters against the Pydantic model, and check required fields.
  def _unwrap_and_validate_params(params: Any, model_class: Type[T], required_fields: List[str] = None) -> Dict[str, Any]: """ Helper function to unwrap and validate parameters. Args: params: The parameters to unwrap and validate. model_class: The Pydantic model class to validate against. required_fields: List of required field names. Returns: A tuple of (success, result) where result is either the validated parameters or an error message. """ # Handle case where params might be wrapped in another dictionary if isinstance(params, dict) and len(params) == 1 and "params" in params and isinstance(params["params"], dict): logger.warning("Detected params wrapped in a 'params' key. Unwrapping...") params = params["params"] # Handle case where params might be a Pydantic model object if not isinstance(params, dict): try: # Try to convert to dict if it's a Pydantic model logger.warning("Params is not a dictionary. Attempting to convert...") params = params.dict() if hasattr(params, "dict") else dict(params) except Exception as e: logger.error(f"Failed to convert params to dictionary: {e}") return { "success": False, "message": f"Invalid parameters format. Expected a dictionary, got {type(params).__name__}", } # Validate required parameters are present if required_fields: for field in required_fields: if field not in params: return { "success": False, "message": f"Missing required parameter '{field}'", } try: # Validate parameters against the model validated_params = model_class(**params) return { "success": True, "params": validated_params, } except Exception as e: logger.error(f"Error validating parameters: {e}") return { "success": False, "message": f"Error validating parameters: {str(e)}", }