_is_auth_error matched the substring '401' anywhere in an error string,
so a latency figure ('retry after 4010 ms'), a request id, or a
workspace name containing those digits classified as an auth failure.
A false positive calls _force_reauth, which runs a real token exchange;
the server rotates the refresh token on every exchange, and a lost
rotation response leaves Hermes holding a superseded token whose later
replay revokes the whole grant — the exact wedge this branch fixes.
The status attribute check (SDK AuthenticationError carries status=401)
does the real work and stays first. A concrete non-401 status now wins
over ambiguous text. The text fallback keeps only specific markers:
'invalid or expired access token', 'authentication failed' (not bare
'authentication', which also matches auth-infrastructure outage
messages), 'unauthorized', and '401' only with HTTP context ('HTTP
401', 'status 401'), never as a bare number. The classifier is biased
toward false negatives: a missed auth error costs one un-recovered
call, a false positive spends a rotation.
Also redacts token values in _record_auth_failure, _auth_error_message,
and the two retry warnings, matching oauth.py. The SDK's auth errors
carry no token values today, but this is the one credential path where
an upstream regression would leak silently.
Tests: the four false-positive strings stay non-auth, HTTP-context 401s
still match, a concrete 429 status beats 'authentication failed' text,
and the recorded failure plus notice redact token values.
Erosika
b1414baa09