If you implemented Cello before 1 September 2026, you’re probably using our Version 1 endpoint for sending events. That endpoint is still supported, and you can find its documentation here.
POST /events endpoint with one endpoint per business event, each with a closed schema and strict validation: undeclared fields are refused, enums are closed, timestamps require an explicit UTC offset, and monetary amounts are integers in the currency’s minor unit. Every violation in a request is reported at once, each with a JSON Pointer to the offending field.
Signup created
Report a referred user creating an account
Purchase created
Report a new purchase or subscription
Purchase refunded
Report a previously reported purchase being refunded
Demo attended
Report a referred user attending a demo call