lambdatest/agent-skills/api-ratelimit-helper

X-RateLimit-Limit: 100
X-RateLimit-Remaining: 42
X-RateLimit-Reset: 1700000060
X-RateLimit-Policy: 100;w=60;comment="per minute"
Retry-After: 18

{
  "error": "rate_limit_exceeded",
  "message": "Too many requests. You have exceeded 100 requests per minute.",
  "retry_after_seconds": 18,
  "limit": 100,
  "window": "60s",
  "reset_at": "2024-01-01T00:01:00Z"
}

GET  /api/v1/account/quota         — current usage vs limits
GET  /api/v1/account/quota/history — usage over time

{
  "plan": "pro",
  "period": "2024-01",
  "limits": { "requests_per_minute": 1000, "requests_per_day": 500000 },
  "usage": { "requests_today": 12345, "requests_this_minute": 234 },
  "resets_at": "2024-02-01T00:00:00Z"
}

import random, time
def retry_with_backoff(fn, max_retries=5, base_delay=1.0, max_delay=60.0):
    for attempt in range(max_retries):
        try:
            return fn()
        except RateLimitError as e:
            if attempt == max_retries - 1:
                raise
            # Use Retry-After header if present, else exponential backoff
            delay = min(
                e.retry_after or (base_delay * (2 ** attempt)),
                max_delay
            )
            # Add jitter to prevent thundering herd
            delay += random.uniform(0, delay * 0.1)
            time.sleep(delay)

States: CLOSED → OPEN → HALF-OPEN → CLOSED
 
CLOSED: normal operation
  - Track failure rate in rolling window
  - If failure rate > threshold (e.g. 50% in 10s): → OPEN
 
OPEN: reject all requests immediately (fail-fast)
  - Return 503 without calling downstream
  - After cooldown period (e.g. 30s): → HALF-OPEN
 
HALF-OPEN: allow limited traffic through
  - If first N requests succeed: → CLOSED
  - If any fail: → OPEN again

POST /api/v1/payments
Idempotency-Key: uuid-v4-client-generated
 
Response includes:
Idempotency-Key: uuid-v4-client-generated
X-Idempotent-Replayed: true  (if this is a duplicate)