recover_with_credential_pool identified "which credential failed" via
pool.current(), a shared mutable pointer that is advanced by every
select() (round-robin rotation, concurrent turns, and other processes
reloading the pool reset it to None). By the time recovery ran, it
routinely pointed at a different, healthy entry — mark_exhausted_and_rotate
then stamped the failing request's error message and reset time onto that
innocent entry. With round_robin and one hard-capped key this
deterministically exhausted the healthy key too and took the entire pool
offline ("no available entries") from a single rate-limited credential.
mark_exhausted_and_rotate already supports api_key_hint for exactly this
(the auxiliary-client path passes it); the main conversation-loop path
never did. Pass agent.api_key — kept in sync with the entry in use by
_swap_credential — as the hint on all four rotation call sites, and make
the "already exhausted → rotate immediately" pre-check look up the failing
entry by key with the same fallback to current().
Adds regression tests that fail on the old attribution logic: a fresh
pool (current() is None) failing on key B must mark entry B, never
entry A.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
schattenan
795bf4a9e6