A person with a Commune account: the readers who join a community and the writers who are credited on an article. Looked up by identifier or by username, and only ever as a public profile: never an email address.
The one account read from the inside is the credential's own. GET /me
is the same person as the profile above plus the address and verification
state that one withholds, and it sits here rather than under a heading of
its own because it is the private view of exactly what this tag already
documents. It needs no permission at all.