API Reference
Rate Limits
API rate limits and how to handle them.
The Castor Flow API enforces rate limits to ensure fair usage and platform stability.
Limits by plan
- Starter: 60 requests per minute
- Growth: 300 requests per minute
- Scale: 1,000 requests per minute
Rate limit headers
Every response includes headers showing your current usage:
X-RateLimit-Limit: 300
X-RateLimit-Remaining: 287
X-RateLimit-Reset: 1741257600Handling rate limit errors
When you exceed the rate limit, the API returns HTTP 429. Check the Retry-After header and wait that many seconds before retrying.
💡 Tip
Use exponential backoff when retrying 429 responses. Most integrations should never hit rate limits during normal usage.