Rate limits #

Requests to the books API are limited to 300 a minute per user (conventions.rate_limit_per_minute in /meta). Every response carries the limit and how much of it is left:

X-RateLimit-Limit: 300
X-RateLimit-Remaining: 287

A request over the limit returns 429 with a Retry-After header, in seconds:

{
  "status": "error",
  "detail_code": 429,
  "help": "https://microbooks.io/docs/getting-started/conventions/#errors",
  "errors": "Too many requests. Retry after the Retry-After interval."
}

This limit is separate from your plan’s monthly API call cap, which also returns 429 once reached (errors.subscription explains which). Plans and their caps are described under Subscription.