Rate Limiting
A cap on how many API requests you can make in a given time window — set by Anthropic to manage server load and prevent abuse. If your application sends too many messages too quickly, you'll hit a rate limit and requests will be rejected until the limit resets. For most teams starting out, rate limits aren't a problem. At scale — processing thousands of documents a day, for example — you need to design your system to handle them.
In practice
Your app makes 1,000 API calls in 10 seconds during a traffic spike and Anthropic starts rejecting requests with 429 errors. Rate limiting is Anthropic's ceiling on how fast you can call the API. For production apps, you need to handle these errors gracefully — queue requests, add retry logic, or upgrade your tier to get higher limits.
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