Last updated: 2026-04-18

What is Rate limit (HTTP 429)?

A cap on how many requests or tokens you can send in a given window (per minute, per day). When exceeded, the provider returns HTTP 429 'Too Many Requests' with an x-ratelimit-reset header telling you when the window resets. Common causes: heartbeat firing too often, retry loops after errors, free-tier daily cap, or provider-wide throttling. Mitigations: provider fallback in config, exponential backoff on retries, cheaper models for routine tasks, or upgrading your plan tier.

See also

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