Status: Phase 1 stub. Matures in Phase 5 per §8.1.

Statement

Product surfaces — messaging, groups, vault, mail, calls, profile, auth, landing — render through a semantic palette: success, warning, error, info, neutral, plus the brand gradient as a single accent reserved for primary CTAs. The 8-color diagnostic palette (F-3) does not appear on product surfaces.

Why

Product users do not learn that pink "means" anything. They learn that red "means" error and green "means" success. A semantic palette respects that prior learning instead of asking the user to absorb a new color taxonomy. The audit caught two leaks where diagnostic-palette colors crossed into product context (call-quality indicator, vault-share ribbon) — both produced moments where the user paused trying to decode the color.

The brand gradient is the one exception: it is the system's signature, used at most once per screen per B-1 (single-CTA-per-screen discipline). It is not a "color" in the semantic-palette sense; it is a moment.

How

src/components/design-system/colors.ts exports the semantic palette as a separate named map from the diagnostic palette. Tailwind utility classes consume semantic tokens. The brand gradient is exposed only via <Button variant="primary"> and a small set of explicitly-marked surfaces (logo, hero accents).

Phase 5 deepens this stub with the cross-mode contrast matrix (§2.7), the brand-gradient counter-examples (audit pattern #36), and per-component citations.