The credential-pool Codex refresh path synced tokens from auth.json and
then POSTed the refresh_token to OpenAI's token endpoint without holding
the cross-process auth-store lock across the whole read->POST->write-back
sequence. Because Codex refresh tokens are single-use, two concurrent
Hermes processes could both adopt the same on-disk token and both POST
it; the loser got refresh_token_reused / invalid_grant.
Wrap the Codex OAuth branch of _refresh_entry in the existing shared
_auth_store_lock (reentrant, cross-process flock) using the same
extended-timeout pattern resolve_codex_runtime_credentials() already
uses. A waiting process now blocks on the lock and, once inside, the
in-lock re-sync picks up the rotated token the winner persisted and
skips its own POST. Also send User-Agent: hermes-cli/<version> on the
refresh request.
Credit @cooper-oai (#34820) for identifying the concurrent-refresh
reuse race; this ships the narrow lock-serialization fix without the
separate Codex auth-store partition.
CredentialPool._sync_device_code_entry_to_auth_store rotated single-use
OAuth refresh tokens but wrote the new chain only into the active profile
store. When a profile resolves a grant from the global-root fallback
(read_credential_pool, #18594) and the pool then refreshes it, root was
left holding a now-revoked refresh token — every other profile reading the
stale root grant subsequently died with refresh_token_reused / invalid_grant
once its access token expired.
This is the credential-pool analog of #43589 (which fixed the non-pool xAI
refresh path in _save_xai_oauth_tokens). Detect the read-from-root case
(profile lacks its own providers.<id> block) BEFORE the profile save and,
after it, write the rotated chain back to the global root via a best-effort,
seat-belted write-through. A profile that genuinely shadows root (owns the
block) is untouched; classic mode (profile == root) is a no-op; a failed root
write never breaks the profile's own save. Covers openai-codex (reported),
xai-oauth, and nous through the shared sync path.
