4xx Client error
429 Too Many Requests
The client sent too many requests in a given time (rate limiting).
The server may include a Retry-After header saying how long to wait. Very common with LLM and other metered APIs.
Common causes and fixes
- Respect
Retry-After; otherwise retry with exponential backoff plus random jitter. - Reduce concurrency, batch requests, or cache results.
- For LLM APIs, limits apply to requests and tokens per minute — check your usage tier or request a higher limit.
- Don’t retry in a tight loop: it keeps you rate-limited.
Example response
HTTP/1.1 429 Too Many Requests
Retry-After: 30
X-RateLimit-Remaining: 0
Date: Thu, 22 Oct 2026 08:00:00 GMT Check a URL’s status with curl -I https://example.com, which prints the status line and headers.