OpenRouter returns 429 in two shapes: an account-level throttle on the
user's key, and an upstream-provider throttle (DeepSeek/Anthropic/etc.
rate-limiting OpenRouter's aggregate traffic). The classifier treated
both identically and rotated/exhausted OPENROUTER_API_KEY on every 429 —
burning the key for ~24min and silently disabling auxiliary features
(compression, summarization, vision) on an upstream throttle where the
key was healthy.
Add a FailoverReason.upstream_rate_limit classified from OpenRouter's
unambiguous wrapper message "Provider returned error" (the same signal
the metadata-raw parser already trusts). Recovery skips credential
rotation and defers to the fallback chain to switch models instead.
Co-authored-by: Hermes Agent <127238744+teknium1@users.noreply.github.com>
Zane Ding
ac380050ea