Messages - 3.4.2 unclear what is JWT/JWS/JWE encoded

The endpoint.... "MAY return claims in JWT format which can be JWS [JWS] signed or JWE [JWE] encrypted."

It is unclear what exactly is JWT/JWS/JWE encoded: - just the claims, each one separately - the whole ID Token - if so, it should be specified what the point is of echo-ing back a JWT/JWS/JWE structure when the client presumably was not able to process it on its own