May an OAuth 2.0 access token be a JWT?

Question

From what I can tell, the OAuth 2.0 specification is extremely vague in terms of what form an access token should take:

The token may den

Answer 1

As long as the Authorization Server and the Resource Server agree on what the access token means, it doesn't matter what their content is. So the only reason you could have a problem would be if you were using different libraries or frameworks when implementing those two servers.