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EffiLink can track when recipients open your emails and when they click links inside them. Engagement data flows back to your account in real time and can be consumed via webhooks, giving you the insight you need to understand campaign performance, debug delivery issues, and power downstream automations. Tracking is available for both the REST API and SMTP integrations and can be enabled per-request.

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Tracking opens

An open is recorded when a recipient’s email client loads the invisible tracking pixel that EffiLink embeds in the email body.

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REST API

Set trackOpen to 1 in your request body:

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SMTP

Add the X-Easeye-API header with track_open set to 1:
Open tracking relies on image loading. Recipients who block remote images in their email client, or use a plain-text view, will not generate an open event even if they read the email. Open counts should be treated as a lower-bound estimate, not an exact figure.

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Tracking clicks

A click is recorded when a recipient clicks a link inside the email. EffiLink rewrites all <a href> links to pass through its click-tracking service before redirecting to the final destination.

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REST API

Set trackClick to 1 in your request body:

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SMTP

Add track_click to the send_options in the X-Easeye-API header:
When click tracking is enabled globally, every link in the email is rewritten. To opt a specific link out of click tracking — for example, an unsubscribe link where you don’t want the redirect — add the ef:disable-tracking attribute to the anchor tag:
The ef:disable-tracking attribute is stripped from the rendered email — recipients will not see it in the source.
The ef:disable-tracking attribute must be lowercase. Click tracking must be enabled via trackClick: 1 (REST API) or track_click: 1 in send_options (SMTP) for per-link exclusion to have any effect.

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Unique message IDs for deduplication

Assign a uniqueMsgID to each message to prevent duplicate sends and to correlate tracking events back to a specific message in your own system.

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REST API

  • Maximum 50 bytes
  • Alphanumeric characters and dashes only

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SMTP

Use the X-Easeye-UniqueMsgID header:
If EffiLink receives a second send request with the same uniqueMsgID within the deduplication window, the duplicate is suppressed — protecting your recipients from receiving the same email twice due to retry logic or application bugs.

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Consuming tracking events via webhooks

Open and click events are emitted as webhook payloads that EffiLink delivers to your configured endpoint in real time. This lets you:
  • Update a CRM record when a lead opens a proposal email
  • Trigger a follow-up automation when a user clicks a call-to-action
  • Log engagement data to your own analytics store
To set up a webhook listener and view the event schema, see Webhooks.

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Tracking reference summary