> For the complete documentation index, see [llms.txt](https://docs.vsat.dev/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.vsat.dev/understanding-datadome/dd-surfaces.md).

# The three surfaces

DataDome challenges in three shapes. Which one you get is chosen by the tenant's policy and your trust level.

## tags: the always-on signal

Every protected page loads DataDome's `tags` script, which collects \~228 signals (canvas, WebGL, fonts, timing, feature detection, a V8 call-stack fingerprint) and POSTs them to `/js/`. This runs **even when you are not challenged**: it is how DataDome scores you for next time. Solved by [`POST /tags`](/endpoints/tags.md).

## interstitial: the device check

A `403` carrying `dd={'rt':'i'}` is an **interstitial**: a full-page device check that runs a heavier JS bundle (module 872) and POSTs a `plv3` payload. Clear it and you get a fresh `datadome` cookie and a redirect back to the page. This is the common desktop challenge. Solved by [`POST /interstitial`](/endpoints/interstitial.md).

## slider: the captcha

A `403` carrying `dd={'rt':'c'}` is a **slider captcha**. The simple (`noPuzzle`) variant is a "slide to confirm" with a deterministic offset, with no image gap to find; what is graded is the telemetry of the drag plus a canvas/worker fingerprint. Solved by [`POST /slider`](/endpoints/slider.md).

{% hint style="info" %}
️ A **cold** slider (served on request one, no interstitial first) on a Windows UA is exit-reputation gated (a real browser is hard-blocked there too) and is refused with `422`. A **chained** slider (after an interstitial) is solvable.
{% endhint %}


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