Dath (Irish: colour — the thing itself, before anyone has an opinion about it). Colour measured rather than eyeballed: OKLCH lightness against the mode's band, OKLCH chroma against the floor below which a hue reads as grey, OKLab delta-E between slots under simulated protan and deutan (tritan reported) by the Machado-Oliveira-Fernandes 2009 transforms at severity 1.0, OKLab delta-E under NORMAL vision because full-colour readers must be able to tell neighbours apart too, and the WCAG contrast ratio of every mark against the surface. THE VERDICT IS A ROW, NEVER A BARE SCORE: each check returns its own name, its own state and a sentence with the offending values written into it, so a reader never goes looking behind a number to find which colour is the problem. WARN IS NOT FAIL AND THE DIFFERENCE IS RULED: adjacent CVD in the 6-8 band and contrast under 3:1 are WARNs legal only with mandatory secondary encoding, while the normal-vision floor is a HARD gate that secondary encoding does not excuse and weak pairs are not masked to keep an existing palette validating. Ordinal ramps take their own four checks — monotone lightness, a visible step gap, a light end that clears the surface, one hue — because the categorical checks fail a correct ramp by design. It measures and never decides: nothing here has taste, and the two structural rules that cannot be computed from hexes are named as uncomputable rather than pretended at. No clock, no disk, no network, no DOM, zero imports.
Irish dath (colour, hue); colour named directly as the thing itself, before any judgment is passed on it.
Colour measured rather than eyeballed — the thing itself, before anyone forms an opinion about it. It measures and never decides; nothing in it carries taste.