Rate-limited requests will return a rate_limited error code (HTTP response status 429). The rate limit for incoming requests is an average of 60 requests per minute. Some bursts beyond the average rate are allowed.
Integrations should accommodate variable rate limits by handling HTTP 429 responses and respecting the Retry-After response header value, which is set as an integer number of seconds. Requests made after waiting this minimum amount of time should no longer be rate limited.
Alternatively, rate limits can be accommodated by backing off (or slowing down) the speed of future requests. A common way to implement this is using one or several queues for pending requests, which can be consumed by sending requests as long as Certify does not respond with an HTTP 429.