The Token Introspection extension defines a mechanism for resource servers to obtain information about access tokens. With this spec, resource servers can check the validity of access tokens, and find out other information such as which user and which scopes are associated with the token.
Token Introspection is meant for first-party / internal use only. The endpoint should not be exposed publicly.
You can find more details on this endpoint in the
ORY Hydra API Docs. You can also use the CLI command
hydra token introspect <token>.
Another helpful resource is Token Introspection Endpoint.