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Rate Limiting

Rate limiting caps how many requests an API or system will accept per second/minute/day — the default protection against abuse and the constraint your integrations must respect.

What is rate limiting?

Rate limiting is the policy that caps how many calls a client can make to a service within a window. Limits are usually per API key, per IP, or per account, and exceeding them returns a 429 Too Many Requests error.

Why it matters

  • Every external API has limits; integration code that ignores them breaks at scale
  • Self-imposed limits protect your reputation (sending 5,000 cold emails an hour from one mailbox = spam folder)
  • Distinct from throttling, which slows requests; rate limits reject them

Patterns for staying inside limits

  • Token bucket — refills tokens over time, lets bursts through if you've saved up
  • Leaky bucket — smooth out request rate to a steady stream
  • Exponential backoff — on 429, wait, then retry; double the wait each retry
  • Concurrency caps — limit in-flight requests, not just request rate

How TexAu helps

TexAu handles per-source rate limits internally — set the cap once, the workflow respects it across pagination, retries, and parallel runs.

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