Pointer cancellation
What this criterion checks
This criterion maps to 2.5.2 Pointer Cancellation. A detailed plain-language description is maintained in the WebLens criteria catalogue; the WCAG sub-test breakdown below describes exactly what the agent checks and what it does not.
How it's assessed
WebLens walks each user journey, captures a screenshot at every step, and an agent reasons over that evidence. See the how WebLens works for the full pipeline and the deterministic checks layered in for accessibility.
Sub-test coverage
2.5.2 Pointer Cancellation is broken into 4 sub-tests. Coverage is honest about where the agent is reliable, where it only partially checks the requirement, and where a human reviewer is still needed.
2 full2 partial
- No down-event executionFull
Our tool uses a dedicated behavioral plugin that programmatically probes each pointer-interactive element on the page. It simulates a pointerdown event without releasing and detects whether the function executes immediately on the down-event by monitoring for DOM mutations, URL navigation, dialog openings, and new windows. Standard HTML controls (buttons, links, inputs) that use the native click event are automatically excluded as they naturally fire on the up-event. Known gaps: cross-origin iframes, closed shadow roots, canvas-based interactions, and multi-step gesture sequences are not probed.
- Up reversalFull
Our tool tests up reversal by performing a single uninterrupted pointerdown-then-pointerup sequence on the element and comparing the page state after release against the baseline state captured before pressing. If the final state matches the original, the up-event reversed the down-event effect and the element passes. Page state comparison includes URL, DOM mutations, dialogs, and active element tracking.
- Abort or undo availablePartial
Our tool tests the abort mechanism by simulating a pointerdown on the element, moving the pointer outside the element boundaries, then releasing. If no persistent effect occurred, the abort mechanism is confirmed. However, it does not test for undo mechanisms available after action completion — only pre-completion abort by moving the pointer away. Drag-and-drop interactions (draggable=true) are tested via this abort probe as well.
- Essential down-event exceptionPartial
When an element fails all three mechanical checks (no down-event, abort, up reversal), our tool flags it with a needs-essential-check marker for downstream review. Determining whether down-event activation is essential (e.g., keyboard emulator, musical instrument, timing-critical game controls) requires semantic understanding of the element's purpose and is deferred to human or LLM-based judgment. The tool does not autonomously determine essentiality.
How reliable it is
This criterion is still building up testing data, so confirm its findings as you review. See Accuracy & confidence for how the confidence tags are set.