> ## Documentation Index
> Fetch the complete documentation index at: https://docs.apollodeploy.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Tracking domains and engagement signals

> Configure project-wide tracking and interpret opens, clicks, reads, and scroll events correctly

Signal supports project defaults for open tracking, click tracking, unsubscribe tracking, read engagement, and scroll depth.
A send request can override open, click, unsubscribe, and read-engagement behavior for one message.

## Tracking behavior

| Setting              | Current behavior                                       |
| -------------------- | ------------------------------------------------------ |
| Open tracking        | Adds a tracking image to compatible HTML content       |
| Click tracking       | Rewrites eligible links through Signal tracking        |
| Unsubscribe tracking | Enables Signal's unsubscribe-link handling             |
| Read engagement      | Records supported read-engagement events when entitled |
| Scroll depth         | Project setting that depends on read engagement        |

Text-only messages can support eligible click and unsubscribe rewriting.
Pixel-based open behavior requires HTML.
Test mode does not perform real recipient tracking.

## One project-wide tracking domain

A project currently supports one tracking domain.
You may open its configuration from a domain page, but saving it changes tracking for all project sends.
It is not scoped only to the sending domain page you opened.

## DNS setup

1. Choose a dedicated host such as `track.company.com`.
2. Copy the tracking CNAME name and target returned by Signal.
3. Publish the CNAME in direct DNS mode.
4. Save the host and run verification.
5. Send one controlled real message.
6. Test an eligible link and unsubscribe path that your configuration enables.

A proxy or flattening behavior that hides the expected CNAME target can prevent verification.

## Interpreting signals

`opened` means the tracking image loaded.
`clicked` means a rewritten link was followed.
Those are technical observations, not guaranteed human actions.
Image blocking can prevent an open event; privacy proxies can load images; security scanners can follow links.

Use engagement events alongside delivery, application conversion, topic consent, and customer-support evidence.

<Warning>
  Changing the project tracking host affects every send that inherits project tracking settings.
  Treat it as a project-level change.
</Warning>

<Card title="Tracking settings" icon="route" href="/signal/dashboard/domains/tracking">
  Review dashboard configuration and verification steps.
</Card>