calcom.onMeetingStarted subscribes at a meeting’s scheduled start time. Cal.com sends this delayed event as a flat booking object; booking fields such as uid are at the event root.
automations/on-meeting-started.automation.ts
Event
Additional provider fields are preserved.
Automate.ax creates and maintains the Cal.com webhook, verifies
x-cal-signature-256, and deduplicates provider retries. Use calcom.onEvent when one automation should receive every supported Cal.com event.