Just in case anyone else comes across this, I dug through the source and found that the body just describes the expiration timing: https://github.com/prisma/prisma/blob/master/server/libs/auth/src/main/scala/com/prisma/auth/Auth.scala#L46 It's a JSON w/ keys

exp

and

nbf

, which correspond to the expiration time in seconds and the current time ("not before") in seconds.