The @defer and @stream directives are not enabled by default. In order to use these directives, you must add them to your GraphQL Schema and use the experimentalExecuteIncrementally function instead of execute.

import {
  GraphQLSchema,
  GraphQLDeferDirective,
  GraphQLStreamDirective,
  specifiedDirectives,
} from 'graphql';
 
const schema = new GraphQLSchema({
  query,
  directives: [
    ...specifiedDirectives,
    GraphQLDeferDirective,
    GraphQLStreamDirective,
  ],
});
 
const result = experimentalExecuteIncrementally({
  schema,
  document,
});

If the directives option is passed to GraphQLSchema, the default directives will not be included. specifiedDirectives must be passed to ensure all standard directives are added in addition to defer & stream.