inbox.email.sent

{
  "type": "inbox.email.sent",
  "created_at": "2026-09-29T12:00:00.000Z",
  "data": {
    "source": "system",
    "inbox_id": "b3e2b2b6-3f0e-4c8e-9ad3-2f43a1e2c7f1",
    "thread_id": "7c1f0a2e-5d3b-4e8a-9f61-2b8d4c6e1a90",
    "email_id": "4ef9a417-02e9-4d39-ad75-9611e0fcc33c",
    "thread": {
      "object": "inbox_thread",
      "id": "7c1f0a2e-5d3b-4e8a-9f61-2b8d4c6e1a90",
      "subject": "Question about my invoice",
      "folder": "inbox",
      "labels": [],
      "read": true
    },
    "email": {
      "id": "4ef9a417-02e9-4d39-ad75-9611e0fcc33c",
      "direction": "outbound",
      "from": "Ada from Support <support@example.com>",
      "to": ["steve.wozniak@gmail.com"],
      "cc": [],
      "bcc": [],
      "reply_to": [],
      "subject": "Re: Question about my invoice",
      "message_id": "<0100019a4ef9a417@email.amazonses.com>",
      "attachments": [],
      "read": true,
      "received_at": "2026-09-29T12:00:00.000Z"
    }
  }
}

{
  "type": "inbox.email.sent",
  "created_at": "2026-09-29T12:00:00.000Z",
  "data": {
    "source": "system",
    "inbox_id": "b3e2b2b6-3f0e-4c8e-9ad3-2f43a1e2c7f1",
    "thread_id": "7c1f0a2e-5d3b-4e8a-9f61-2b8d4c6e1a90",
    "email_id": "4ef9a417-02e9-4d39-ad75-9611e0fcc33c",
    "thread": {
      "object": "inbox_thread",
      "id": "7c1f0a2e-5d3b-4e8a-9f61-2b8d4c6e1a90",
      "subject": "Question about my invoice",
      "folder": "inbox",
      "labels": [],
      "read": true
    },
    "email": {
      "id": "4ef9a417-02e9-4d39-ad75-9611e0fcc33c",
      "direction": "outbound",
      "from": "Ada from Support <support@example.com>",
      "to": ["steve.wozniak@gmail.com"],
      "cc": [],
      "bcc": [],
      "reply_to": [],
      "subject": "Re: Question about my invoice",
      "message_id": "<0100019a4ef9a417@email.amazonses.com>",
      "attachments": [],
      "read": true,
      "received_at": "2026-09-29T12:00:00.000Z"
    }
  }
}

Inboxes are currently in private beta and only available to a limited number of users. The response shape might change before GA.Get early access if you’re interested in testing this feature.Once you have access, upgrade your Resend SDK to use the new methods:

npm install resend@6.33.0

npm install -g resend-cli@2.25.0

Event triggered whenever an outbound email is accepted for delivery and added to a thread. Note: source is always system, because the email pipeline sends this event, even when the API or an agent sent the email. Note: When the email comes from a draft, inbox.draft.sent fires first, from the send call. This event follows once the email is accepted for delivery.

Response Body Parameters

All webhook payloads follow a consistent top-level structure with event-specific data nested within the data object.

string

The event type that triggered the webhook (e.g., inbox.email.sent).

string

ISO 8601 timestamp when the webhook event was created.

object

Event-specific data containing detailed information about the event. The data object for the inbox.email.sent event contains the following parameters:

Hide object parameters

api | dashboard | agent | system

What made the change

string

The ID of the inbox

string

The ID of the thread

string

The ID of the email

object

The thread, as it is when the webhook is sent. Absent when the thread no longer exists

Hide thread object

string

Always inbox_thread

string

The ID of the thread

string | null

The subject of the thread

inbox | archive | spam | sent | trash

The folder the thread lives in

array

The labels attached to the thread, each with an id, name, and color

boolean

True only when every message in the thread is read

object

The email, as it is when the webhook is sent, without html or text. Fetch the body with Retrieve Thread Email. Absent when the email no longer exists

Hide email object

string

The ID of the email

inbound | outbound

Whether the email was received by the inbox or sent from it

string

Sender email address

string[]

The recipients of the email

string[]

The CC recipients of the email

string[]

The BCC recipients of the email

string[]

The Reply-To addresses

string | null

The subject of the email

string | null

The Message-ID header of the email

array

The attachments on the email

Hide attachment object

string

The ID of the attachment

string | null

The filename of the attachment

number | null

The size of the attachment in bytes

boolean

Whether the email has been read

string

ISO 8601 timestamp when the email arrived or was sent

{
  "type": "inbox.email.sent",
  "created_at": "2026-09-29T12:00:00.000Z",
  "data": {
    "source": "system",
    "inbox_id": "b3e2b2b6-3f0e-4c8e-9ad3-2f43a1e2c7f1",
    "thread_id": "7c1f0a2e-5d3b-4e8a-9f61-2b8d4c6e1a90",
    "email_id": "4ef9a417-02e9-4d39-ad75-9611e0fcc33c",
    "thread": {
      "object": "inbox_thread",
      "id": "7c1f0a2e-5d3b-4e8a-9f61-2b8d4c6e1a90",
      "subject": "Question about my invoice",
      "folder": "inbox",
      "labels": [],
      "read": true
    },
    "email": {
      "id": "4ef9a417-02e9-4d39-ad75-9611e0fcc33c",
      "direction": "outbound",
      "from": "Ada from Support <support@example.com>",
      "to": ["steve.wozniak@gmail.com"],
      "cc": [],
      "bcc": [],
      "reply_to": [],
      "subject": "Re: Question about my invoice",
      "message_id": "<0100019a4ef9a417@email.amazonses.com>",
      "attachments": [],
      "read": true,
      "received_at": "2026-09-29T12:00:00.000Z"
    }
  }
}

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inbox.email.sent

Response Body Parameters