The Event API relies on your server being able to handle large amount of POST calls on your webhook(s).
We advise you to follow the following guidelines for implementation and usage:
Process the received payload asynchronously : as much as possible, the webhook script should rely on an asynchronous consumer process that will use the data saved by your webhook. You should keep out of your webhook logic all cross matches of the delivered events with other resources of our API or your internal database. This step will allow your webhook to answer our calls in a timely manner and avoid timing out and being retried by our server.
Check your server logs regularly for any errors : all non 200 errors would be retried and could cause an increasing volume of calls to your system.
Leverage the transactional message tagging to sim.