Send Failed
Send Failed callbacks are triggered when an email could not be processed or delivered. The event_meta field will be null for this event type — error details are provided in the top-level error field.
Send Failed Webhook Payload
| Parameter | Type | Required | Description | Example |
|---|---|---|---|---|
channel | string | true | Always email | email |
event_type | string | true | Always email_send_failed | email_send_failed |
batch_id | string | true | UUID auto-generated per API send request and returned in the send response. Shared across all recipients (to, cc, bcc) of that single send. | 550e8400-e29b-41d4-a716-446655440000 |
message_id | string | true | Internal identifier for the individual recipient record | 507f1f77bcf86cd799439011 |
tag | string | false | Custom tag sent with the email | welcome-email |
bulk_tag | string | false | User-provided string for grouping multiple sends across separate API calls | campaign-april |
event_meta | null | true | Always null for this event type | null |
error | number | true | Error code describing the failure. See Errors for a full list of codes. | 4101 |