Limits exist so a misbehaving or looping agent can't flood your channel or burn through your credits. In normal use you'll rarely see them.
60 calls a minute per connection, across all its actions.
One connection can start at most 10 Series renders and 10 one-off renders an hour, and the account as a whole caps at 20 renders an hour across every connected agent.
Heavier actions like publishing, channel changes and re-rolls carry hourly caps of their own, per connection.
When a cap trips, the agent gets a clear error saying how long to wait, so a well-behaved agent backs off on its own.
Rate caps are courtesy throttles. The hard stop is credits: every render is checked against your balance before it starts, and a job that costs more than you have is refused. An agent can never spend past what you've already bought, and it can never buy more on its own.
Wondering what an agent has been doing? Settings → Authorized agents shows its recent calls. Email [email protected] if something looks off.