Reference
Rate limits
Successful responses (HTTP 2xx) include the rate-limit headers below. A 429 response also includes the active throttle window when a rate or quota window is exhausted. Treat the headers as part of your control loop rather than retrying blindly.
Headers
X-RateLimit-LimitRequests allowed in the active hourly rate-limit or monthly quota window.
X-RateLimit-RemainingRequests remaining in the active hourly rate-limit or monthly quota window.
X-RateLimit-ResetUnix timestamp (seconds) when the active rate-limit or quota window resets.
Retry-AfterSeconds until the next request is allowed on 429 responses.
Other 4xx responses may omit these headers. Read the error body code first; only retry automatically when the status and headers describe a retryable throttle window.
Quota exhaustion
Quota exhaustion returns 429. Back off until X-RateLimit-Reset (Unix seconds) before retrying. Retrying without honouring the reset header risks extending the throttle window.