No tooltip only values
no-tooltip-only-values
No tooltip-only values — hover is not the values channel (keyboard/touch/AT). Dual-cite empty/failure “don’t hide the only message in a dismissible overlay.”
Description
No tooltip-only values—hover is not the values channel for keyboard, touch, or assistive technology. Related empty or failure guidance: do not hide the only message in a dismissible overlay. Pass when values are available without hover via labels, table, or equivalent. Fail when the only values live in a hover tooltip, blocking non-hover access to the numbers.
When to use
Exposing numeric values on charts for keyboard, touch, and AT users.
Not when
Values available only inside a hover tooltip.
Agent hint
Expose values via labels, table, or equivalent—never tooltip-only.
Values are available without hover (labels, table, or equivalent).
The only values are in a hover tooltip.
Citations
NSW — Charts and graphs
https://designsystem.nsw.gov.au/docs/content/methods/charts-and-graphs.html