ServiceNow MCP Server

Instructions

Implementation Reference

• src/servicenow_mcp/tools/change_tools.py:302-393 (handler)

  The core handler function that executes the update_change_request tool. It validates input parameters using UpdateChangeRequestParams, prepares the update data, and sends a PUT request to the ServiceNow change_request table API endpoint.

  def update_change_request(
      auth_manager: AuthManager,
      server_config: ServerConfig,
      params: Dict[str, Any],
  ) -> Dict[str, Any]:
      """
      Update an existing change request in ServiceNow.
  
      Args:
          auth_manager: The authentication manager.
          server_config: The server configuration.
          params: The parameters for updating the change request.
  
      Returns:
          The updated change request.
      """
      # Unwrap and validate parameters
      result = _unwrap_and_validate_params(
          params, 
          UpdateChangeRequestParams, 
          required_fields=["change_id"]
      )
      
      if not result["success"]:
          return result
      
      validated_params = result["params"]
      
      # Prepare the request data
      data = {}
      
      # Add 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.state:
          data["state"] = validated_params.state
      if validated_params.risk:
          data["risk"] = validated_params.risk
      if validated_params.impact:
          data["impact"] = validated_params.impact
      if validated_params.category:
          data["category"] = validated_params.category
      if validated_params.assignment_group:
          data["assignment_group"] = validated_params.assignment_group
      if validated_params.start_date:
          data["start_date"] = validated_params.start_date
      if validated_params.end_date:
          data["end_date"] = validated_params.end_date
      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/change_request/{validated_params.change_id}"
      
      try:
          response = requests.put(url, json=data, headers=headers)
          response.raise_for_status()
          
          result = response.json()
          
          return {
              "success": True,
              "message": "Change request updated successfully",
              "change_request": result["result"],
          }
      except requests.exceptions.RequestException as e:
          logger.error(f"Error updating change request: {e}")
          return {
              "success": False,
              "message": f"Error updating change request: {str(e)}",
          }

• src/servicenow_mcp/tools/change_tools.py:38-52 (schema)

  Pydantic model defining the input schema for the update_change_request tool, including required change_id and optional fields for updating the change request.

  class UpdateChangeRequestParams(BaseModel):
      """Parameters for updating a change request."""
  
      change_id: str = Field(..., description="Change request ID or sys_id")
      short_description: Optional[str] = Field(None, description="Short description of the change request")
      description: Optional[str] = Field(None, description="Detailed description of the change request")
      state: Optional[str] = Field(None, description="State of the change request")
      risk: Optional[str] = Field(None, description="Risk level of the change")
      impact: Optional[str] = Field(None, description="Impact of the change")
      category: Optional[str] = Field(None, description="Category of the change")
      assignment_group: Optional[str] = Field(None, description="Group assigned to the change")
      start_date: Optional[str] = Field(None, description="Planned start date (YYYY-MM-DD HH:MM:SS)")
      end_date: Optional[str] = Field(None, description="Planned end date (YYYY-MM-DD HH:MM:SS)")
      work_notes: Optional[str] = Field(None, description="Work notes to add to the change request")

• src/servicenow_mcp/utils/tool_utils.py:497-503 (registration)

  Registers the update_change_request tool in the tool_definitions dictionary used by the MCP server, associating the handler function, input schema, return type, description, and serialization method.

  "update_change_request": (
      update_change_request_tool,
      UpdateChangeRequestParams,
      str,
      "Update an existing change request in ServiceNow",
      "str",
  ),

• src/servicenow_mcp/tools/__init__.py:23-32 (registration)

  Imports the update_change_request function into the tools package namespace, exposing it for use.

  from servicenow_mcp.tools.change_tools import (
      add_change_task,
      approve_change,
      create_change_request,
      get_change_request_details,
      list_change_requests,
      reject_change,
      submit_change_for_approval,
      update_change_request,
  )