There is a limit of 300 requests per 10 seconds for each API key and no more than 100 requests per 10-second interval for each token. If a request exceeds the limit, Trello will return a 429 error
Welcome to the Atlassian Community!
It's mainly about limiting external software or power-ups from overloading your Trello with requests to see or do stuff.
It looks like you're new here. Sign in or register to get started.