If you're issuing authentication tokens using OpenID Connect in Orchard Core CMS to authenticate users to access an API, like the GraphQL API, you'll need to enable Token Validation when configuring OpenID Connect for authentication in Orchard Core.
GraphQL in Orchard Core
Quick tip on setting GraphQL permissions in Orchard Core CMS, especially when you're using Orchard Core CMS as a headless CMS via the GraphQL API. This GraphQL tutorial shows how to enable GraphQL permissions for a user role.
Orchard Core CMS supports GraphQL. It's perfect for using Orchard Core CMS as a Headless CMS or static website generator. Query content using any REST Client, Angular, React, or Vue. Learn more about GraphQL in this Orchard Core CMS tutorial.