Introspection endpoint is protected by PAT token.
Java interface
```
https://github.com/GluuFederation/oxAuth/blob/master/Client/src/main/java/org/xdi/oxauth/client/uma/RptStatusService.java#L26-26
```
You can take git repo and check usages of this interface if you need concrete example.
Thanks,
Yuriy Z