At ArcGIS Enterprise 10.9.1, named users in the Enterprise portal must be licensed with the ArcGIS Knowledge user type extension to create, edit, and update Knowledge Graph Server services. At ArcGIS Enterprise 11.0, your account no longer requires the ArcGIS Knowledge user type extension, but you must be signed in to the Enterprise portal to create, edit, and update Knowledge Graph Server services.
A knowledge graph service's dataModel resource allows an administrative client to modify the entity types and relationship types that are available in the knowledge graph service.
The response format. The only supported format is html.
The following is a sample request URL for a knowledge graph service named SupplyChain: