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Documentation Index

Fetch the complete documentation index at: https://docs.impulselabs.ai/llms.txt

Use this file to discover all available pages before exploring further.

The Impulse Labs API enforces a sliding window rate limit per user per 60-second period.

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Limits by plan

PlanRequests / 60 seconds
Pro120
Team300
Enterprise1 000
Limits apply to validated inference requests — each call to POST /infer counts as one request against your limit.

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Rate limit headers

Every response from POST /infer includes these headers:
HeaderTypeDescription
X-RateLimit-LimitintegerMaximum requests allowed in the window
X-RateLimit-RemainingintegerRequests remaining in the current window
X-RateLimit-ResetintegerUnix timestamp (seconds) when the window resets
Retry-AfterintegerSeconds to wait (only present on 429 responses)

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Reading headers

curl -si -X POST "https://inference.impulselabs.ai/infer" \
  -H "Authorization: Bearer $IMPULSE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"deployment_id": "my-model", "inputs": {}}' \
  | grep -i x-ratelimit

# X-RateLimit-Limit: 120
# X-RateLimit-Remaining: 118
# X-RateLimit-Reset: 1708346460

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Handling 429 Too Many Requests

When you exceed the limit, the API returns: 
HTTP/1.1 429 Too Many Requests
Retry-After: 34
X-RateLimit-Limit: 120
X-RateLimit-Remaining: 0
X-RateLimit-Reset: 1708346460

{
  "valid": false,
  "error": "Rate limit exceeded",
  "limit": 120,
  "retry_after_seconds": 34
}
  1. Read the Retry-After header and wait that many seconds before retrying.
  2. Do not retry immediately in a tight loop — this will keep triggering the limit.
  3. For batch workloads, spread requests over time or use exponential backoff.
Python — respect Retry-After
import time, requests

def safe_infer(session, payload, headers):
    while True:
        resp = session.post(
            "https://inference.impulselabs.ai/infer",
            json=payload,
            headers=headers,
        )
        if resp.status_code == 429:
            wait = int(resp.headers.get("Retry-After", 5))
            print(f"Rate limited. Retrying in {wait}s...")
            time.sleep(wait)
            continue
        resp.raise_for_status()
        return resp.json()

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Upgrading your plan

If you consistently hit rate limits, consider upgrading to a higher plan at app.impulselabs.ai/billing. For custom limits or Enterprise pricing, contact us.