frontend-design - SKILL.md Agent Skill

name: frontend-design description: >- Create distinctive, production-grade frontend interfaces with high design quality. Use when building web components, pages, artifacts, posters, or applications (websites, landing pages, dashboards, React components, HTML/CSS layouts, or when styling/beautifying any web UI). Generates creative, polished UI that avoids generic AI aesthetics. scope: dev license: Complete terms in LICENSE.txt source: https://github.com/anthropics/skills/blob/main/skills/frontend-design/SKILL.md metadata: internal: true

Frontend Design

This skill guides creation of distinctive, production-grade frontend interfaces. Implement real working code with strong product judgment, excellent accessibility, and a clear visual point of view.

The user may ask for a component, page, full app, dashboard, marketing surface, or restyle. Before coding, understand the audience and pick a direction that fits the product instead of defaulting to generic SaaS polish.

Design Thinking

Before coding, decide:

Purpose: What workflow does this surface make easier? What is the primary action?
Audience: Who will use it repeatedly, and what should feel fast, calm, playful, premium, editorial, technical, or utilitarian?
Tone: Choose a concrete aesthetic direction: refined minimal, dense operations console, editorial, playful, industrial, warm handmade, high-contrast data tool, etc.
Information hierarchy: What must be visible in the first five seconds, and what should be progressively disclosed?
Differentiation: What makes this feel designed for this exact domain?

Then implement working code that is cohesive, accessible, responsive, and polished in small details: typography, spacing, copy, motion, empty states, loading states, focus states, and error states.

Minimalism And Progressive Disclosure

Default to Apple/Linear-level restraint: make the primary workflow obvious, then remove everything that does not help that workflow right now. A polished UI often has fewer visible controls, fewer borders, fewer labels, and fewer explanatory surfaces than the first reasonable implementation.

Start by subtracting: Before adding a visible control, banner, toolbar row, card, or explanatory block, ask what can be removed, merged, renamed, or moved into an existing affordance.
One primary action: Each surface should have one dominant next action. Secondary actions belong in menus, popovers, command palettes, disclosure rows, or contextual hover/focus states unless they are used constantly.
Progressively disclose rare work: Advanced options, diagnostics, metadata, settings, import/export, destructive actions, and inspection tools should stay tucked away until requested. Prefer small icon triggers with tooltips, popovers, drawers, or detail panels over permanent chrome.
Keep chrome quiet: Avoid new always-visible bars, badges, callouts, helper text, and counters unless they prevent mistakes or are central to repeated use. Status can often be a dot, ring, muted count, or tooltip.
Favor content over containers: Do not wrap every section in a card. Use whitespace, alignment, typography, dividers, and full-width bands before adding boxes.
Design for repeated use: Production app UI should feel calm after the hundredth use. If a control shouts, animates, explains itself, or occupies a full row for an occasional action, hide or compress it.
Make absence intentional: Empty states should be sparse and action-oriented. Do not fill blank space with marketing copy, decorative art, or lists of features just because the screen feels empty.
Use familiar primitives: Icon buttons need clear tooltips. Menus, popovers, tabs, switches, and segmented controls should carry complexity instead of exposing every option at once.

Aesthetic Guidelines

Typography: Use the product's existing type system first. For net-new public pages, choose characterful but readable type and keep sizing appropriate to the surface.
Color and theme: Use semantic tokens and CSS variables. Avoid one-note palettes and default purple/blue gradients unless the brand demands them.
Motion: Prefer purposeful transitions and small state changes. Use CSS transitions/keyframes unless the app already uses a motion library.
Composition: Match the workflow. Operational apps should be dense and scannable; marketing or portfolio pages can be more immersive.
Visual assets: Websites, games, and object-focused pages need real or generated media when images help users understand the subject.
Responsive fit: Text must not overflow buttons, cards, tabs, sidebars, or fixed-format tools. Use stable dimensions for boards, grids, toolbars, and counters.

Agent-Native UI Rules

Agent-native apps use React, Vite, Tailwind CSS, shadcn/ui, and @tabler/icons-react.
Use shadcn/ui primitives for standard UI: DropdownMenu, Popover, Dialog, AlertDialog, Sheet, Tabs, Tooltip, Select, Command, Sidebar, Table, Card, Badge, Skeleton, and related primitives.
When touching shadcn/ui components, also read shadcn-ui if it exists. That skill covers components.json, CLI docs, component composition, theming, and registry workflows.
Check app/components/ui/ before importing a shadcn component. If a primitive is missing, add it from the app root with pnpm dlx shadcn@latest add <component>, then review the generated file.
Do not build custom dropdowns, menus, popovers, modals, or confirmations with manual absolute positioning and click-outside effects.
Never use browser dialogs (window.alert, window.confirm, window.prompt). Use AlertDialog, Dialog, or app-specific confirmation UI.
Use Tabler icons for all first-party UI icons. Do not add Lucide, Heroicons, inline SVG icon sets, or emoji icons.
Use useActionQuery and useActionMutation from @agent-native/core/client for action-backed UI. Standard CRUD should go through actions, not custom /api/ routes.
Keep UI optimistic where possible: update cache and navigation immediately, then reconcile or roll back on mutation result.
Custom styles belong in Tailwind classes, component CSS, or the existing global CSS theme file; avoid inline styles.

shadcn/ui Design Rules

Use built-in component variants first (variant, size) before overriding classes.
Use semantic tokens (bg-background, text-muted-foreground, border-border, bg-primary) instead of raw Tailwind colors for app chrome and reusable components.
Use gap-* in flex/grid layouts instead of space-x-* or space-y-*.
Use size-* when width and height are equal, and truncate instead of spelling out overflow/ellipsis/nowrap.
Use cn() from the local utils alias for conditional classes.
Dialog, Sheet, Drawer, and AlertDialog content must have an accessible title. Use sr-only only when the visible design already communicates the title.
Put menu/list items inside their group primitives: SelectGroup, DropdownMenuGroup, CommandGroup, and equivalents.
Use full Card composition when the content has a title, description, content, or actions. Do not dump complex cards into a single CardContent.
Use ToggleGroup for small option sets, Switch for binary settings, Checkbox for multi-select, RadioGroup for one-of-many, and Slider/inputs for numeric values.
For forms, prefer the app's existing shadcn form pattern. If newer Field, FieldGroup, or InputGroup primitives are installed or appropriate to add, use them instead of raw layout divs.
Loading states use Skeleton, Progress, Spinner, or the app's existing loading primitives. Empty states should have one clear next action.

Anti-Patterns

Avoid:

Generic AI aesthetics: purple gradients, glassy cards everywhere, vague sparkle language, decorative blobs, and context-free hero sections.
Custom reimplementations of shadcn primitives.
Raw color overrides on shared components when semantic tokens or variants would work.
New always-visible controls for rare actions. Prefer menus, popovers, sheets, tabs, collapsibles, or advanced sections.
Full-width banners, persistent helper rows, decorative cards, or explanatory chrome for status that could be a compact affordance.
Treating progressive disclosure as optional. If a control is not part of the main daily workflow, hide it until context, hover, focus, or explicit user intent makes it relevant.
UI cards nested inside other cards.
Text or icons that resize or shift fixed-format UI on hover/loading.

Verification

For substantial frontend work:

Run the relevant formatter/checks.
Start the dev server when the app needs one.
Verify with browser screenshots at desktop and mobile widths.
Check interactive states: hover, focus, loading, empty, error, and destructive confirmations.

Related Skills

shadcn-ui — shadcn CLI, component docs, composition rules, theming, and registries
self-modifying-code — The agent can edit source code to apply design changes
storing-data — All data lives in SQL; use actions for data access
actions — useActionQuery/useActionMutation hooks for frontend data fetching