Webhook event reference

Webhooks let your systems react to activity as it happens. When a subscriber opens or clicks a Broadcast, unsubscribes, or a delivery fails, the platform sends an HTTP POST to the endpoint you register. This page lists the outbound event types and the shape of the JSON payload each one carries.

Every event shares a common envelope (event id, event type, timestamp, and an object containing event-specific fields). The exact field names and which events are enabled are configured per account — (confirm the exact steps in your account).

Reference

Event type	When it fires	Key payload fields
broadcast.delivered	The message was accepted by the subscriber's mail server	subscriber_email, broadcast_id, edition_id, timestamp
broadcast.opened	A subscriber opened the Edition	subscriber_email, broadcast_id, user_agent, timestamp
broadcast.clicked	A subscriber clicked a tracked link	subscriber_email, broadcast_id, url, link_label, timestamp
broadcast.bounced	Delivery failed	subscriber_email, bounce_type (hard/soft), reason, timestamp
subscriber.unsubscribed	A subscriber opted out	subscriber_email, list_id, source, timestamp
subscriber.complained	A subscriber marked the message as spam	subscriber_email, broadcast_id, timestamp

Field names above are representative; treat them as placeholders and verify against a live sample from your account.

Notes

• Envelope. Each POST body wraps the event in a common structure — an id, an event (type), a created_at timestamp, and a data object holding the fields above.
• Delivery and retries. Endpoints should return a 2xx promptly. Non-2xx responses are typically retried with backoff; design handlers to be idempotent using the event id.
• Ordering. Events are not guaranteed to arrive in order. Use the timestamp, not arrival order, to reconstruct a sequence.
• Security. Verify each request before trusting it (for example, a signature header or a shared secret) and respond only over HTTPS.
• Batching. Some accounts receive one event per request; others may receive small batches. Handle both a single object and an array.

Related

• Send a transactional email
• Metrics dictionary
• Manage the suppression list

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Canonical terms: Author, Edition, Folder (Project Folder), Broadcast. See the Glossary.