The exact `The '<model>' model is not supported when using Codex with a
ChatGPT account.` 400 classified as format_error, so a two-entry openai-codex
pool never tried its second account: the turn failed as a malformed request
even though the other account was entitled (#71970). #106475 covered the
single-credential case and explicitly left the multi-entry case to rotation,
but no rotation branch existed for it.
- classify the exact normalized text as FailoverReason.model_entitlement
(rotate + fallback, never retry); arbitrary 400s stay format_error
- recover_with_credential_pool rotates once on that reason; the pool records
it through the existing model_cooldowns path (Anthropic per-model 429), so
only (credential, model) is benched: other models keep using the account,
and `hermes auth` reset clears the marker with everything else
- _mark_entitlement_rejected_model gates on pool.has_available(model=...)
instead of entry count, so once every account rejects the model it falls
back to the #106475 session marker (fallback walk skips it, no oscillation)
Salvages the design of #71973 by @kilhyeonjun on the current classifier
tables and the model-cooldown substrate that landed since.
Co-authored-by: kilhyeonjun <kboxstar@gmail.com>
