inbox.thread.created

Event triggered whenever the first email of a thread lands in the inbox, inbound or outbound.

Note: source is always system, because the email pipeline sends this event, even when the API or an agent sent the email.

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

• type (string) — The event type that triggered the webhook (e.g., inbox.thread.created).

• created_at (string) — ISO 8601 timestamp when the webhook event was created.

• data (object) — Event-specific data containing detailed information about the event. The data object for the inbox.thread.created event contains the following parameters:

  object parameters

  • source (api | dashboard | agent | system) — What made the change
  • inbox_id (string) — The ID of the inbox
  • thread_id (string) — The ID of the thread
  • email_id (string) — The ID of the email
  • thread (object) — The thread, as it is when the webhook is sentobject (string) — Always inbox_threadid (string) — The ID of the threadsubject (string | null) — The subject of the threadfolder (inbox | archive | spam | sent | trash) — The folder the thread lives inlabels (array) — The labels attached to the thread, each with an id, name, and colorread (boolean) — True only when every message in the thread is read
  • email (object) — The email, as it is when the webhook is sent, without html or text. Fetch the body from the APIid (string) — The ID of the emaildirection (inbound | outbound) — Whether the email was received by the inbox or sent from itfrom (string) — Sender email addressto (string[]) — The recipients of the emailcc (string[]) — The CC recipients of the emailbcc (string[]) — The BCC recipients of the emailreply_to (string[]) — The Reply-To addressessubject (string | null) — The subject of the emailmessage_id (string | null) — The Message-ID header of the emailattachments (array) — The attachments on the emailid (string) — The ID of the attachmentfilename (string | null) — The filename of the attachmentsize (number | null) — The size of the attachment in bytesread (boolean) — Whether the email has been readreceived_at (string) — ISO 8601 timestamp when the email arrived or was sent

{
  "type": "inbox.thread.created",
  "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": false
    },
    "email": {
      "id": "4ef9a417-02e9-4d39-ad75-9611e0fcc33c",
      "direction": "inbound",
      "from": "Steve Wozniak <steve.wozniak@gmail.com>",
      "to": ["support@example.com"],
      "cc": [],
      "bcc": [],
      "reply_to": [],
      "subject": "Question about my invoice",
      "message_id": "<CAF7c1f0a2e5d3b@mail.gmail.com>",
      "attachments": [
        {
          "id": "2a0c9ce0-3112-4728-976e-47ddcd16a318",
          "filename": "invoice.pdf",
          "size": 48213
        }
      ],
      "read": false,
      "received_at": "2026-09-29T12:00:00.000Z"
    }
  }
}