This is a DESIGN-SPEC skill, not an implementation skill. Non-negotiable rules: 1. Do NOT write production UI code from this skill. Produce a spec + a locked design language and DELEGATE the build to an engineering agent. We own the design spec; the agent implements it. 2. Commit to ONE distinctive aesthetic identity BEFORE specifying screens, and pass the counterfactual default test: if you'd produce this same look for any similar brief, it's a default — change it. 3. Ban AI-slop BY NAME (`references/anti-slop.md`). The slop test gates the work: if someone could say "AI made that" with no doubt, it failed. 4. LOCK the design language in `DESIGN.md` and bind every screen to it. Variation within identity, NEVER between. Re-read `DESIGN.md` first on every later feature or session. 5. If the user gives inspiration links, VISIT them with the `browse` skill and synthesize — never clone a single reference, and never inherit its slop. 6. Run the Design Pre-Flight gate before handoff. If a single box can't be honestly ticked, it is not done. 7. Keep the rigor that sets us apart: state coverage, flows/edge cases, and accessibility — never skip them.

frontend-design-ui-ux

Inputs

• $request: Feature, page, component, or UX problem to design — plus optional inspiration URLs.

Goal

Produce a design package that is distinctive, consistent, and buildable — a spec a delegated engineering agent implements directly. All artifacts are written under .ulpi/design/:

• .ulpi/design/DESIGN.md — the locked design language (identity, palette, type, scales, signature, voice, chosen design system). Project-wide; re-read first every session.
• .ulpi/design/<feature>.md — the per-feature spec: user flows + states, component specs, and the build handoff (target agent + acceptance criteria). Binds to DESIGN.md.

Step 0: Discovery & inputs

Resolve: target users · product goal · device/usage context · existing design-system or brand constraints · accessibility expectations. Ask once: "Any reference sites or designs you admire? Paste 1–4 URLs."

If the problem is underspecified, ask — but at most a couple of focused questions; never a long interrogation. Success criteria: the problem is framed in user + product terms, and inspiration links (if any) are collected.

Step 1: Inspiration intake (optional)

If the user gave links, VISIT each with the browse skill, extract its design DNA (type, color, shape, spacing, layout), and distill a one-line DNA note per site. Synthesize across them — never clone one. If browse is unavailable or a link is unreachable, ask the user to describe the vibe and proceed.

Load references/inspiration-intake.md. Success criteria: each reference reduced to reusable DNA, with what to take and what to reject — or cleanly skipped.

Step 2: Design Read & aesthetic direction

Approach as a design lead who would never ship a templated look. Kill the default-aesthetic reflex before any tokens:

• Emit a one-line Design Read (the feeling + the bet).
• Commit to one named aesthetic direction from the menu in references/anti-slop.md; justify it from the brief (and the inspiration DNA, if any).
• Run the counterfactual default test: would this look be your answer for ANY similar brief? If so, change it.
• Optionally set taste dials (design_variance / motion_intensity / visual_density, 1–10) and match complexity to the direction (maximalist → elaborate; minimal → restraint, precision, whitespace).

Load references/anti-slop.md for the direction menu, the pattern vocabulary, and the named bans. Success criteria: a committed, brief-specific direction that is not a generic default.

Step 3: Derive & LOCK the design language → write .ulpi/design/DESIGN.md

Decide the register (brand vs product) and, for product, the design system to build on (see references/design-system-routing.md). Then derive and LOCK the identity: palette (OKLCH, tinted neutrals, 60-30-10, WCAG-checked), type roles paired on a contrast axis, ONE spacing/radius/motion scale, the Signature, and the voice. Write it to .ulpi/design/DESIGN.md — the consistency source of truth every screen binds to.

Load references/design-language-lock.md (artifact + lock rules), references/design-tokens-template.md (derivation method), and references/design-system-routing.md (brief→system map). Success criteria: a complete, locked .ulpi/design/DESIGN.md; no generic default identity.

Step 4: Model flows and states

Document the primary journey, branching/decisions, and the full state model — loading, empty, partial, success, error — plus edge cases (refresh, session expiry, back, offline). Write into .ulpi/design/<feature>.md. Use references/user-flow-template.md. Success criteria: behavior is covered across states, not just the happy path.

Step 5: Specify components and interaction rules

For each component define: purpose, variants, props/data, states, interaction feedback, responsive behavior, and accessibility (ARIA, keyboard, screen-reader, focus). Bind every visual value to .ulpi/design/DESIGN.md; append into the same .ulpi/design/<feature>.md. Use references/component-spec-template.md. Success criteria: a delegated engineer can build it without guessing, and nothing drifts from the locked identity.

Step 6: Design Pre-Flight gate

Run references/design-preflight.md end to end — identity lock, anti-slop, state coverage, accessibility, layout craft, cognitive load, and the scored self-critique. Several items are mechanical counts. Fix any failing box or any axis scored ≤ 2, state in one line WHAT you changed and WHY (revise-and-justify), then re-run. Success criteria: every box ticked and no critique axis ≤ 2.

Step 7: Build handoff (delegate the build)

Finalize the delegation brief at the end of .ulpi/design/<feature>.md: the target engineering agent, the chosen design_system (+ its setup note), and the acceptance criteria — with the instruction: "Implement exactly this spec. Theme the design system with our locked tokens; do NOT redesign or re-implement its components." The building is delegated to the agent; this skill never writes the UI.

Agent Selection

Criteria	Target Agent
Server-side rendering / SEO / App Router / Server Actions	nextjs-senior-engineer
Pure SPA / client-only / CLI web UI / Electron-Tauri	react-vite-tailwind-engineer
Static site with no SSR	Either (ask user)
Unclear	Ask user

Success criteria: a delegated agent can pick up .ulpi/design/DESIGN.md + .ulpi/design/<feature>.md and implement it directly, without redesigning.

Guardrails

• Do not implement production UI code from this skill; produce the spec and hand off.
• Do not ship a generic default identity — derive palette and type per brief; the slop test gates output.
• Do not let screens drift from DESIGN.md: variation within identity, never between.
• Do not clone a single inspiration reference, and never inherit its slop.
• Do not skip accessibility, state coverage, or responsive behavior — they are our edge.
• Do not produce vague design prose when a concrete artifact is needed.
• Do not block if browse or an image tool is absent — degrade gracefully and proceed from the brief.

When To Load References

• references/inspiration-intake.md — visiting reference links with browse and extracting DNA (Step 1).
• references/anti-slop.md — the direction menu, named AI-slop bans, and the slop test (Steps 2, 3, 6).
• references/design-language-lock.md — the DESIGN.md artifact and the consistency lock rules (Step 3).
• references/design-system-routing.md — the brief→design-system map + honesty rule (Step 3, product register).
• references/design-tokens-template.md — the per-brief color/type derivation method + neutral scales (Step 3).
• references/user-flow-template.md — user journeys and acceptance flows (Step 4).
• references/component-spec-template.md — component briefs and interface contracts (Step 5).
• references/design-preflight.md — the pre-handoff quality + consistency gate (Step 6).

Output Contract

Write under .ulpi/design/ and report:

1. the Design Read + committed aesthetic direction (and inspiration DNA, if any)
2. .ulpi/design/DESIGN.md — the locked design language (register, design system, palette, type, scales, signature, voice)
3. .ulpi/design/<feature>.md — flows and states
4. — component specs (same file)
5. Pre-Flight result (every box ticked, no critique axis ≤ 2)
6. build handoff — target agent + design system + acceptance criteria ("implement exactly this; do not redesign")