https://www.rfc-editor.org/info/rfc7662/
RFC 7662: OAuth 2.0 Token Introspection | RFC Editor
This specification defines a method for a protected resource to query an OAuth 2.0 authorization server to determine the active state of an OAuth 2.0 token and...
token introspectionrfcoautheditor
https://oauth.net/2/token-introspection/
Token Introspection — OAuth 2.0
token introspectionoauth