---
title: "Email Opened"
method: POST
path: "MessageLoaded"
tags: ["Engagement Events"]
---

# Email Opened

`POST MessageLoaded` (webhook)

Triggered when a recipient opens an email (tracking pixel loaded).

**Requirements:**
- Open tracking must be enabled for your domain
- HTML emails only (plain text emails cannot be tracked)
- Recipient's email client must load images

**Note:** Some email clients pre-fetch images or block tracking pixels,
so open rates may not be 100% accurate.

## Payload

- WebhookPayload — Webhook event payload sent to your configured endpoint
  - `event` 'MessageSent' | 'MessageDelayed' | 'MessageDeliveryFailed' | 'MessageBounced' | 'MessageHeld' | 'MessageLoaded' | 'MessageLinkClicked' | 'DomainDNSError', required — The type of event that occurred
  - `timestamp` integer, required — Unix timestamp when the event occurred
  - `payload` WebhookEventData, required — Event-specific data
    - `message` WebhookMessageData — Email message information
      - `id` string — Internal message ID
      - `token` string — Message token for identification
      - `to` string, email — Recipient email address
      - `from` string, email — Sender email address
      - `subject` string — Email subject line
      - `tag` string — Tag applied to the email
      - `message_id` string — RFC 5322 Message-ID header
      - `metadata` object — Custom metadata attached when the email was sent. Use this to correlate webhook events with your internal systems.
    - `status` string — Status from the mail server
    - `details` string — Additional details or error message
    - `output` string — Raw server output
    - `url` string — Clicked URL (for MessageLinkClicked events)
    - `ip_address` string — IP address of recipient (for open/click events)
    - `user_agent` string — User agent of recipient (for open/click events)

## Acknowledgement `200`

Webhook received successfully

---

[API](https://skmtc.dev/arkhq-io/apis/ark-email-api.md) · [All operations](https://skmtc.dev/arkhq-io/apis/ark-email-api/llms.txt) · [OpenAPI document](https://skmtc-service-production.skmtc.workers.dev/v1/apis/arkhq-io/ark-email-api/revisions/dfe78a4bb565/schema)