<PackageReference Include="Newtonsoft.Json" Version="11.0.2" />

Newtonsoft.Json.Schema.UndefinedSchemaIdHandling

Specifies undefined schema Id handling options for the JsonSchemaGenerator.

JSON Schema validation has been moved to its own package. See http://www.newtonsoft.com/jsonschema for more details.
namespace Newtonsoft.Json.Schema { public enum UndefinedSchemaIdHandling { None, UseTypeName, UseAssemblyQualifiedName } }