Event Types

Delivery events

Event	Description
MessageSent	Message accepted and queued for delivery
MessageDelivered	Successfully delivered to recipient’s mail server
MessageDelayed	Delivery temporarily delayed (will retry)
MessageHeld	Message held for review (e.g., credential reputation)
MessageDeliveryFailed	Permanent delivery failure
MessageBounced	Recipient server returned a bounce

Engagement events

Event	Description
MessageOpened	Recipient opened the email (via tracking pixel)
MessageLinkClicked	Recipient clicked a tracked link

Lifecycle events

Event	Description
DomainDNSError	DNS configuration issue detected for a domain
CredentialLocked	SMTP/API credential suspended (reputation issue)
CredentialUnlocked	Credential restored after reputation reset

Event payload structure

All events share a common structure:

{
  "event": "MessageDelivered",
  "timestamp": 1743339600,
  "uuid": "evt_abc123",
  "payload": {
    // Event-specific data
  }
}

MessageDelivered / MessageSent payload

{
  "id": 1234,
  "token": "abc123",
  "server_id": 1,
  "rcpt_to": "[email protected]",
  "mail_from": "[email protected]",
  "subject": "Welcome!",
  "message_id": "[email protected]",
  "timestamp": 1743339600,
  "status": "Sent",
  "details": "Message delivered to remote server",
  "output": "250 2.0.0 OK"
}

MessageBounced payload

{
  "id": 1234,
  "token": "abc123",
  "rcpt_to": "[email protected]",
  "mail_from": "[email protected]",
  "subject": "Welcome!",
  "bounce_type": "hard",
  "bounce_code": "550",
  "bounce_message": "5.1.1 User unknown"
}

Filtering events

When configuring a webhook, you can subscribe to specific events. Only selected events will be delivered to your endpoint.