Textual (DOM) Assertions

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Textual assertions extract data from the page’s DOM: element states, attributes, and computed styles that aren’t always visible in a screenshot.

When It’s Used

Element states: disabled, enabled, checked, readonly, expanded
CSS properties with exact values: font-size: 16px, opacity: 0.5, display: none
HTML attributes: placeholder, aria-*, data-*, class, id, href, src, type, value
Attribute existence: “has placeholder”, “has aria-label”
Exact CSS color values: rgb(255,0,0), #ff0000

Examples

Assertions

Assert: the submit button is disabled
Assert: the checkbox is checked
Assert: the input field has placeholder "Enter email"
Assert: the element has aria-label "Close dialog"
Assert: the font-size of the heading is 24px

Extractions

Extract the href of the first link
Store the value attribute of the email input
Get the class of the error message element

When NOT to Use

For visible text content (prices, labels) → use Visual
For color names like “red background” → use Visual (DOM may return transparent or inherited values)
For network/console/cookie data → use DevTools

How It Works

KaneAI captures the DOM snapshot of the page
The AI model identifies the target element and extracts the requested property
The value is compared against the expected value

​When It’s Used

​Examples

​Assertions

​Extractions

​When NOT to Use

​How It Works