In solid-contrib/test-suite#36 , I found that a custom IDP that simply gave away bearer tokens without attempting to authenticate a user would best fulfill the needs of a test suite. Then, I had second thoughts, because the existence of such an IDP would subvert the mechanism of acl:AuthenticatedAgent. I figured we should therefore have some kind of shared secret between a test runner and the system under test. But then, I figured, if we can create such an IDP, so can anybody else.

We can certainly specify that an IDP must authorize an agent, there could even be laws against it in some jurisdictions, but we probably cannot make them go away entirely if there is value to some.

Thus, acl:AuthenticatedAgent does not mean acl:ReasonablyWellBehavedAndKnownAgent, it is marginally different from foaf:Agent, in that you could have agents with a valid bearer token that has been through no authentication process.

Whether this should make us re-evaluate whether acl:AuthenticatedAgent should exist at all, or if we should just adjust user's expectations towards it, I don't know, but it should be discussed.