Currently hydra issues opaque tokens but has the capabilities to switch to JWT in the future. There is a warden HTTP API endpoint that you can use to inspect tokens and use hydra's access control. I will probably add a more common token info endpoint or a OAuth2 Token Introspection endpoint ( https://tools.ietf.org/html/rfc7662 ) later on.
I haven't used kong yet but from my first impression it should be possible to use hydra together with kong.