How to Fix Rate Limit Errors from an AI API

A 429 Too Many Requests error means you hit the provider's rate limit. It is rarely a sign of a bug; it means your code sends requests faster than your tier allows. This guide reads the error correctly and fixes it with backoff and pacing.

What you need

• Code that calls an AI API and sometimes fails with 429
• Access to the provider's rate-limit docs for your tier
• About 10 minutes

Step 1: Read the error and headers

The response usually tells you how long to wait. Log the status and the retry-after header before you change any logic.

Step 2: Retry with exponential backoff

On a 429, wait and try again, doubling the delay each time with a little randomness. This clears short bursts without hammering the API.

async function withRetry(fn, max = 5) {
  for (let i = 0; i < max; i++) {
    try { return await fn(); }
    catch (e) {
      if (e.status !== 429 || i === max - 1) throw e;
      const wait = (2 ** i) * 500 + Math.random() * 250;
      await new Promise(r => setTimeout(r, wait));
    }
  }
}

Step 3: Cap concurrency

Firing a hundred calls at once guarantees a 429. Limit how many run in parallel so you stay under the per-minute ceiling.

Step 4: Batch where the API allows it

Result: transient limits are absorbed by backoff, sustained load stays under the ceiling via concurrency caps, and 429 errors stop reaching your users.