Skill: Design Doctrine

Step 0: is the kit here? This skill reads files from the kit. Check once: ls ${CLAUDE_SKILL_DIR}/../../../tokens >/dev/null 2>&1 && echo KIT_OK || echo KIT_MISSING On KIT_MISSING only the skill folders were installed, which is what npx skills add does. Say so plainly, point the user at npx ux-ui-agent-skills init or the plugin install, and stop. Do not guess the contents of a file you could not open.

A plugin's root CLAUDE.md is not loaded as project context, so the always-on brief travels here instead. Read this before the first line of any design work, then load the rule file for the territory you are actually in.

Verification protocol - run gates, never claim

1. Never state a number you did not measure. Any contrast ratio, "WCAG pass", or "100%" must come from running a gate and reporting its real output. If you have not run it, say "not verified yet."
2. Verify every state, not just resting. node ${CLAUDE_SKILL_DIR}/../../../scripts/gate.mjs verify_states.mjs <file> [--dark] measures default, hover and focus - a button that passes at rest can fail on hover.
3. One command before reporting done: node ${CLAUDE_SKILL_DIR}/../../../scripts/accuracy_report.mjs. Report the real N/N line. It is all-or-nothing.
4. Build with the gates, not after them. Fix and re-run until green; never announce success between failures.
5. Render and LOOK. Gates pass while a UI is still visibly broken. Screenshot the harness in both themes, click every control, and confirm the state changed.
6. Responsive is gated too: node ${CLAUDE_SKILL_DIR}/../../../scripts/gate.mjs verify_responsive.mjs <file|dir>: no horizontal overflow from 280 to 951px, iPhone Duo included, and a hinge kept clear by any page that answers the fold.
7. Honest scope. The gates prove objective correctness. They never prove taste. For that, run /critique, look at the work yourself, and start from the taste preflight below rather than from default components.
8. SKIPPED is not a pass. With no browser installed a render gate prints SKIPPED and exits 0, reporting nothing. Run single render gates behind DS_REQUIRE_BROWSER=1 so that becomes REQUIRED, FAILING, and fix it with npx playwright install chrome rather than by removing the flag.

Mobile is the base

Base styles ARE the phone layout. Wider screens are layered on with min-width. max-width is not banned - it is right for a genuine narrow refinement, or for a range between two breakpoints - but a desktop-first stylesheet, where the base assumes a wide screen and mobile is patched in afterwards, is a bug.

Measured by ${CLAUDE_SKILL_DIR}/../../../scripts/verify_mobile_first.mjs, which removes every @media and @container rule and renders what is left at 320px. A mobile-first page passes because its base already is the phone layout. A desktop-first page cannot fit.

Two house rules on what never ships

Never ship a native <select>. It draws its own chevron, pressed against the control's edge with no breathing room, and appearance: none plus a custom chevron fights the platform instead of matching the system. Use the Listbox or Combobox pattern in ${CLAUDE_SKILL_DIR}/../../../components/forms-advanced.md: a button trigger that announces the current value, the chevron placed with inner padding from tokens, and full keyboard parity (typeahead, arrows, Home/End, Escape, aria-expanded that really toggles something visible). Losing native select means accessibility stops being free, so the replacement has to pass every state, keyboard and axe gate before it counts. Measured by ${CLAUDE_SKILL_DIR}/../../../scripts/lint_native_select.py.

Never a colored border on one side only of a card, alert, toast or callout - border-left, border-right, border-top, border-bottom, or the logical border-inline-* and border-block-* forms. The tinted 3-4px bar is a generated-UI cliche in every direction, not only on the left: it is decoration standing in for hierarchy the layout never established. Use a full hairline border on all sides, or surface and elevation separation, and carry status with a real icon plus text, never colour alone. Measured on the render by the one-sided accent-border tell in ${CLAUDE_SKILL_DIR}/../../../scripts/slop_tells.mjs.

Taste preflight - before any markup

The gates cannot see this half, so it has to be decided rather than discovered. Write the block into your reply, then build to it. Generating first is where generated-looking work comes from.

Domain:          fintech | editorial | dev-tool | healthcare | consumer | ...
Audience & tone: expert vs first-time, calm vs energetic, premium vs utilitarian
Mood:            the one adjective the result must earn - "expensive", "precise", "warm"
Motion depth:    none | subtle feedback | expressive choreography
Layout family:   the section sequence you will use, named, varied per section
Reference anchor: an archetype or named system to aim at

Break each of these deliberately; they are defects, not starting points.

• Three or four identical equal-weight cards. One thing leads.
• Everything centered. Use asymmetry on a real grid.
• The same left-text / right-image row repeated.
• A heading that is only bold body text. Display type is at least 2.5x body, short, on an 18-24ch measure.
• A drop shadow on every box. Most things are flat.
• #000 on #fff. Off-black on warm-white, from the theme.
• More than one accent. Neutrals carry the weight.
• A colored border on one side only of a card, alert, toast or callout. Full hairline border or surface separation; status by icon plus text, never colour alone.
• Em-dashes in UI copy, marketing filler ("elevate", "seamless", "unlock"), hollow triads, fake labels ("SECTION 01", lorem ipsum).

Depth, and the full Variance Mandate: ${CLAUDE_SKILL_DIR}/../../../taste/design-taste.md. For a whole page or app, use design-screen, which runs this preflight as step 1 of the pipeline.

ABSOLUTE: zero emoji in any output - UI, code, JSON, copy, comments, commit messages. Not as an icon, a bullet, a status dot, or "polish". Emoji are the number-one tell of machine-generated work. Use a lucide icon (inline SVG, currentColor) or plain words. No em dash or en dash either: a colon, a comma or parentheses. Enforced by ${CLAUDE_SKILL_DIR}/../../../scripts/check_no_emoji.py.

The five non-negotiables

1. Token by intent. Pick the token whose meaning matches the action. Destructive actions (Delete, Remove, Revoke) wear action.destructive in every place they appear - the trigger and the confirm dialog both. A blue Delete is a bug. Measured by ${CLAUDE_SKILL_DIR}/../../../scripts/lint_intent.mjs.
2. One theme, one source of truth. Every page renders from the same ${CLAUDE_SKILL_DIR}/../../../tokens/*.json through one CSS-variable layer imported once at the app root. No per-page palette, no hardcoded hex, px, or timing.
3. Every interactive element ships eight states: default, hover, focus, active, disabled, loading (if async), error (if input), and selected (if selectable). The eighth is not optional when the thing can be selected.
4. One thing leads. Every screen has a first place for the eye, and display type is at least 2.5x the body size. Four equal cards means the eye lands nowhere and the screen reads as generated.
5. Output completeness. A partial output is a broken output. Deliver full files, never placeholders. Asked for N components, deliver all N.

Decision framework

User needs, then accessibility, then consistency, then aesthetics, then developer experience. Never sacrifice a higher tier for a lower one. Beautiful but inaccessible is broken; consistent but confusing is the wrong pattern.

Where the depth lives

Then pick the runnable skill for the job: design-tokens, design-component, design-code, design-review, a11y-audit, apply-aesthetic, brandkit, image-to-code, redesign, and the rest. Interrogate the brief first with /grill-me; prove the result with /gate; judge it with /critique.