Call Flow Events & Trigger Reference

Quick Summary

- Events are discrete signals emitted during a session (voice, SMS, chat, email, webhook-driven).

- Triggers listen to chosen events and run actions (e.g., tag, route, notify, call a webhook).

- The UI’s Trigger By list is a curated subset for common workflows; the enum contains the full set.

Typical Session Lifecycle (Voice/SMS)

A common voice session may look like:

START → LISTEN → MESSAGE → (optional TRANSFER → TRANSFER_RING → TRANSFER_PICKED → TRANSFER_END) → FINISH → AFTER_FINISH

For SMS/Chat:

START → MESSAGE (repeats per turn) → FINISH → AFTER_FINISH

Survey subflows and email events can interleave; errors/timeouts/cancellations can short-circuit normal order.

UI “Trigger By” → Event Mapping

The current UI list (TRIGGER\_BY\_OPTIONS) exposes these items:

UI Label (shown)	Underlying Event	Notes
Engagement Accepted	START	Session picked by agent/bot; effective session start
Engagement Refused	REFUSED	Party refused to engage or declined.
Engagement Finished	FINISH	Primary session end
Post-Engagement Processing	AFTER_FINISH	Post-finish cleanup window. Good for trailing automations
In Conversation	MESSAGE	Fires on AI/user message turns
Transfer Initiated	TRANSFER	Generic transfer start event
Transfer Connecting	TRANSFER_RING	~5–7 seconds after dial, while the destination is ringing.
Transfer Failed	TRANSFER_FAILED	Downstream target didn’t accept or errored.
Survey End	SURVEY_END	End of a survey flow.
Reply Email	REPLY_EMAIL	Reply email was generated/sent.
Embedded URL Clicked	LINK_CLICKED	User clicked a trackable link

Important: The UI list does not expose all events from the enum (see full catalog below). If you need one that isn’t visible, ask Platform to expose it or bind via webhook listeners.

Best Practices & Gotchas

Prefer specific events over OTHER for stable automations.
Commit at Engagement Finished, clean up at Post-Engagement Processing to avoid blocking the user experience.
Differentiate transfer stages for accurate SLAs: Transfer Initiated vs. Transfer Connecting vs. Engagement Accepted (post-transfer) vs. Transfer Failed.
Do not assume ordering under error conditions; race conditions can emit out of the usual sequence.
UI coverage: If an event you need isn’t in the Trigger By list, raise a request to expose it or capture via webhook.
Email safety nets: always pair Reply Email flows with EMAIL_ERROR handling.