Get a webhook delivery payload

Authorizations

Authorization

string

header

required

Sendmux API key. Use a root API key for Management API routes, or a mailbox credential for Mailbox API routes. Obtain keys from the dashboard under API Keys.

Path Parameters

public_id

string

required

Webhook public ID

delivery_id

string

required

Delivery-attempt public ID

Response

Delivery payload

enum<boolean>

required

Available options:

true

meta

object

required

Hide child attributes

meta.request_id

string

required

Example:

"req_clxxxxxxxxxxxxxxxxxxxxxxxxx"

data

object

required

Hide child attributes

data.id

string

required

Delivery-attempt public ID

Example:

"whda_clxxxxxxxxxxxxxxxxxxxxxxxxx"

data.event_id

string

required

Webhook event ID

Example:

"evt_clxxxxxxxxxxxxxxxxxxxxxxxxx"

data.event_type

enum<string>

required

Event types a webhook may subscribe to. sendmux.test is accepted so you can verify end-to-end delivery via POST /webhooks/{id}/test.

Available options:

message.delivered,

message.bounced,

message.complained,

message.rejected,

message.delivery_delayed,

message.received,

message.received.spam,

sendmux.test

Example:

"message.bounced"

data.delivery_attempt

integer

required

1-based retry attempt number.

Example:

1

data.created_at

string

required

ISO 8601 attempt timestamp

Example:

"2026-05-21T09:12:00Z"

data.expires_at

string

required

Timestamp when this retained payload expires.

Example:

"2026-05-28T09:12:00Z"

data.payload

object

required

The JSON request body delivered to the webhook endpoint.

Hide child attributes

data.payload.id

string

required

Stable per-event identifier. Also sent in the X-Sendmux-Event-Id header.

Example:

"evt_clxxxxxxxxxxxxxxxxxxxxxxxxx"

data.payload.type

enum<string>

required

Dotted event type. Same value as the X-Sendmux-Event-Type header.

Available options:

message.delivered,

message.bounced,

message.complained,

message.rejected,

message.delivery_delayed,

message.received,

message.received.spam,

sendmux.test

Example:

"message.received"

data.payload.team_public_id

string

required

Team that owns the event.

Example:

"team_clxxxxxxxxxxxxxxxxxxxxxxxxx"

data.payload.occurred_at

string

required

When the event occurred.

Example:

"2026-05-21T09:12:00Z"

data.payload.data

object

required

Hide child attributes

data.payload.data.message_id

string | null

required

Message identifier from the event source.

Example:

"ME3P282MB076951B3AAD3255D686EA8EDCA0F2@example.com"

data.payload.data.message_id_kind

enum<string> | null

required

provider for sending feedback IDs; rfc5322 for inbound email Message-ID header values.

Available options:

provider,

rfc5322

Example:

"rfc5322"

data.payload.data.sendmux_message_id

string | null

required

Sendmux message correlation ID for outbound sending feedback when available.

Example:

null

data.payload.data.sender

string | null

required

Sender/envelope-from address when available.

Example:

"sender@example.com"

data.payload.data.recipients

string[]

required

All affected recipients. Empty for synthetic test events.

Example:

["inbox@example.com"]

data.payload.data.mailbox_id

string | null

required

Mailbox public ID for inbound mailbox events when resolved.

Example:

"mbx_123"

data.payload.data.bounce_type

enum<string> | null

required

Bounce category for message.bounced events.

Available options:

Permanent,

Transient,

Undetermined

Example:

null

data.payload.data.bounce_subtype

string | null

required

More specific bounce category when available.

Example:

null

data.payload.data.complaint_type

string | null

required

Complaint category for message.complained events.

Example:

null

data.payload.data.complaint_subtype

string | null

required

More specific complaint category when available.

Example:

null

data.payload.data.reject_reason

string | null

required

Reject reason for message.rejected events.

Example:

null

data.payload.data.delay_type

string | null

required

Delay category for message.delivery_delayed events.

Example:

null

data.payload.data.delay_expires_at

string | null

required

When delivery retries are expected to stop, when provided.

Example:

null

data.payload.data.is_spam

boolean | null

required

Only populated for inbound mailbox events.

Example:

false

data.payload.data.webhook_id

string | null

required

Target webhook ID for synthetic sendmux.test payloads.

Example:

null

Example:

{
  "id": "evt_clxxxxxxxxxxxxxxxxxxxxxxxxx",
  "type": "message.received",
  "team_public_id": "team_clxxxxxxxxxxxxxxxxxxxxxxxxx",
  "occurred_at": "2026-05-21T09:12:00Z",
  "data": {
    "message_id": "ME3P282MB076951B3AAD3255D686EA8EDCA0F2@example.com",
    "message_id_kind": "rfc5322",
    "sendmux_message_id": null,
    "sender": "sender@example.com",
    "recipients": ["inbox@example.com"],
    "mailbox_id": "mbx_123",
    "bounce_type": null,
    "bounce_subtype": null,
    "complaint_type": null,
    "complaint_subtype": null,
    "reject_reason": null,
    "delay_type": null,
    "delay_expires_at": null,
    "is_spam": false,
    "webhook_id": null
  }
}

Documentation Index

Authorizations

Path Parameters

Response