Share it, then see how it landed.

A private link is only half the job. Stacktree tells you how the page was received: reactions and private notes from viewers, an activity feed and an optional daily digest, and engagement analytics that show the time on page, the scroll depth, and where readers actually lingered. Aggregate and private, never a recording.

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Can you see how someone read a shared page?

Yes. When your agent publishes an HTML page to Stacktree, the link does more than serve the file. Viewers can react and leave a private note on the page. You get an activity feed and an optional daily email of who opened, reacted, and commented. And on Pro, an engagement view shows the typical time on page, the scroll depth, the share of readers who reached the end, and an attention heatmap of where they lingered. All of it is aggregate and non-PII: no session replay, no keystrokes, no identity.

The gap this closes

Most hosts hand you a link and stop. You send a report, a proposal, a dashboard, or a build, and then you are guessing. Did they open it? Did they read past the first screen? Did the pricing section land or get skipped? For a client deliverable, that guess is the whole game.

Stacktree closes the loop in three layers, from the lightest signal to the most detailed, and keeps every one of them on the right side of privacy.

1. Reactions and notes

Turn on the reaction bar for a site and viewers can react with an emoji or leave a short private note, right on the page, with no account. It is the low-friction signal that formal comments miss: a client will tap a heart on a deck they would never write a paragraph about. If several people are viewing at once, reactions animate in live, so a shared review feels shared. Reactions are opt-in per site, so a polished deliverable stays clean until you want them.

2. How it is read

This is the DocSend question applied to agent-built HTML: not just whether the page was opened, but how it was consumed. On Pro, the engagement view shows:

Typical time on page. The median engaged time, counting only when the tab is visible and focused, so a page left open in a background tab does not inflate the number.
Scroll depth and read-to-end rate. How far readers get, and what share reach the bottom.
An attention heatmap. Dwell time by page depth, so you can see the section that held attention and the one that got skipped.

It is aggregate and non-PII by design. There is no recording, no keystroke capture, and no identity attached. It extends the "opened by ~N people" count every page already carries, rather than turning a private link into a tracking product.

3. Notifications that bring you back

Signal is only useful if you see it. The dashboard has an activity feed and a notification bell that show who opened, reacted to, and commented on your pages while you were away, newest first. An optional daily email digest summarises the reactions, notes, and opens once a day. The digest is off by default, and every one carries a one-click unsubscribe.

Why not session replay

Session replay records the viewer. On a private client deliverable that is both a privacy liability and a bad fit for a host that leads with private-by-default links. Stacktree deliberately stops at aggregate: enough to tell the owner how the deliverable landed, without ever surveilling the reader. You get the answer to "did they read it, and what held their attention" without the recording.

How this compares

Criterion	A plain static host	Stacktree
Get a private link	Yes	Yes
Know it was opened	Rarely	Opened by ~N people, on every plan
Reactions + private notes	No	Yes, opt-in per site
Time on page + scroll depth	No	Yes (Pro)
Attention heatmap	No	Yes (Pro)
Activity feed + daily digest	No	Yes, on every plan
Records the viewer	n/a	No, aggregate and non-PII

FAQ

Frequent questions

Can I see how someone read a shared HTML page? +

Yes. Every Stacktree page shows who opened it, and viewers can react and leave a private note. On Pro, engagement analytics adds typical time on page, scroll depth, the share of readers who reach the end, and an attention heatmap of where readers lingered. It is aggregate and non-PII, so you learn how the page landed without surveilling the reader.

Is this session replay or recording? +

No. There is no recording, no keystroke capture, and no identity tracking. Engagement is aggregate: time on page, scroll depth, and dwell by page depth, summed across sessions. It is an extension of the "opened by ~N people" view counting every page already has, not a replay tool.

What do reactions and notes look like for a viewer? +

When you turn reactions on for a site, a small bar appears on the page. A viewer taps an emoji (fire, heart, thumbs-up, and so on) or leaves a short private note, with no account and no sign-in. If more than one person is looking at once, reactions animate in live. The tally and the notes show up in your dashboard.

How do I find out when a page gets opened or reacted to? +

The dashboard has an activity feed and a notification bell that surface who opened, reacted to, and commented on your pages, newest first. You can also turn on a daily email digest that summarises the reactions, notes, and opens once a day. The digest is off by default with one-click unsubscribe.

Which plans include this? +

Reactions, notes, the activity feed, and the daily digest are on every plan, including Free. Engagement analytics (time on page, scroll depth, attention heatmap) is a Pro feature. See pricing.

Is any of this on by default? +

Opened-by counting is on. Reactions are opt-in per site so a client-ready page stays clean until you want the bar. The email digest is opt-in. Engagement is aggregate and non-PII throughout.

Keep reading

Related guides

Send the link. Then find out how it landed.

Reactions and notifications are free. The first publish is anonymous and lives 24 hours.