Rate Limiting

To ensure platform stability and fair usage, the NRS API applies request rate limits.

If your application exceeds the allowed request threshold, the API returns a 429 Too Many Requests response.

---

Rate Limit Response

{
  "ok": false,
  "error": "Rate limit exceeded"
}

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HTTP Status Code

Status Code	Meaning
429	Too many requests

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Recommended Handling

When a 429 response is received:

1. Pause additional requests temporarily.
2. Retry the request after a short delay.
3. Use exponential backoff for repeated retries.

Example retry intervals:

Attempt	Delay
1	1 second
2	2 seconds
3	4 seconds
4	8 seconds

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Best Practices

• Cache responses where possible.
• Avoid sending duplicate requests.
• Queue bulk invoice operations.
• Use retry logic with exponential backoff.
• Monitor application request volume.

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Example Retry Logic

async function requestWithRetry(fn, retries = 4) {
  let delay = 1000;

  for (let i = 0; i < retries; i++) {
    try {
      return await fn();
    } catch (error) {
      if (error.status !== 429) {
        throw error;
      }

      await new Promise(resolve => setTimeout(resolve, delay));
      delay *= 2;
    }
  }

  throw new Error("Rate limit exceeded");
}

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Notes

• Excessive repeated failures may trigger temporary blocking.
• Rate limits may vary between environments.
• Bulk invoice submissions should be batched responsibly.