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Show HN: StyleSeed – a design-rules engine so AI agents stop building generic UI

StyleSeed, a free and MIT-licensed design-rules engine, launched to help AI coding agents like Claude Code, Codex, and Cursor generate consistent, branded UI instead of generic output. The tool enforces brand-specific tokens, a quality gate that scores designs above 80/100, and a persistent lock file to prevent visual drift across sessions.

read23 min views1 publishedJul 15, 2026
Show HN: StyleSeed – a design-rules engine so AI agents stop building generic UI
Image: source

Design judgment for Claude Code · Codex · Cursor · vibe coding — so the output stops looking generated.

One component. Three brand DNAs. Same chat UI morphing across Toss · Raycast · Arc — colors, radius, motion, shadows, gradients all driven by StyleSeed tokens. Just a data-skin

attribute.

Skins are inspired-by token sets — brand-flavored color/radius/shadow/motion values, not recreations of those companies' design languages. The layer that restructures the actual design is the presets ( /ss-restyle, below).

Every design-AI skill makes your UI coherent. StyleSeed also fights the generic-AI look — and enforces it.

Judgment, not data — how designers think, not a palette collection · Fights the AI tells — the default indigo, the icon-chip cliché, template layouts, rainbow lists · A scored Quality Gate — reviews + fixes to ≥80/100 before you see it · Every agent — ships CLAUDE.md

  • AGENTS.md

  • .cursorrules

· A design lock that stops drift · Free & MIT

Full pages: before · after ·

more before/afters →

🔥 We ran an early version of this page through our own gate.

It scored 58/100 → here's the receipt

Same product, six looks — each one /ss-restyle <preset> away. Coherent, distinct, never generic.

Get Started · Engine + Skins · Motion · Skills · Wiki · 한국어

The fastest way — paste this one sentence into Claude Code, Codex, Cursor, or any AI agent. It installs StyleSeed and runs the whole loop:

Install StyleSeed so its checks actually run: `npx skills add bitjaru/styleseed` (if you can't, read https://styleseed-demo.vercel.app/llms-full.txt instead). Then use it for every UI in this project. First, in plan mode, lock my key color, font, and motion with me and save them to STYLESEED.md so they don't drift. Build to the rules with ONE focal point and one accent. Before showing me anything, run the quality gate (`/ss-score` in Claude Code, `$ss-score` in Codex) to ≥ 80 and fix what fails. For a full screen, run `/ss-build` in Claude Code or `$ss-build` in Codex — it enforces this whole loop.

Why the prompt installs first: the quality gate is the step that makes output stop looking generic — but the ss-score

and ss-build

skills can only run if they are installed. Point an agent at the rules-URL alone and the "gate" degrades to an honor-system self-check it usually skips. Installing makes the loop real: the lock persists in STYLESEED.md

(no drift), and the gate actually scores and fixes before you see anything. Can't install? The URL still teaches the rules — just weaker. Works with Claude Code ( CLAUDE.md), Codex / Amp / Gemini CLI (AGENTS.md), and Cursor (.cursorrules) — StyleSeed ships all three. (Planning first is what keeps the result from looking random — see

Troubleshooting.)

What your agent actually does with StyleSeed loaded:

you    ▸  build me a billing settings page
agent  ▸  (plan mode) key color? for billing I'd go deep teal — #0F766E, mood: sharp · calm ·
          trustworthy (not the default indigo). Motion: Snap. ok?  ▸ y
agent  ▸  ✓ wrote STYLESEED.md — skin, accent, font, radius, motion locked, re-read every prompt
agent  ▸  building… running the quality gate before I show you anything
gate   ▸  ✗ two accent colors   ✗ "normal" rows colored   ✗ no empty state   → fixing
agent  ▸  ✓ 88/100 — one accent, grey normal states, real empty/error states. here's the page.

The STYLESEED.md lock is the anti-drift mechanic. Your skin, key color, radius, and motion get written once and the rules make every agent re-read and obey them on

everyprompt — so the design stops being different each session. The Quality Gate then self-reviews and fixes the UI (rainbow lists, two accents, missing states)

beforeyou ever see it — and it can

retrofit an old generic buildtoo.

The rules are the product — and they need zero install or permissions.They're plain markdown (CLAUDE.md

/AGENTS.md

/DESIGN-LANGUAGE.md

), so the prompt above — or just copying those files in — is 90% of StyleSeed with nothing to approve.

Want the 19 ss- agent skills too* (optional automation: setup wizard, review, score)?

npx skills add bitjaru/styleseed

Installs all 19 skills into Claude Code, Codex, Cursor, Gemini CLI, Amp and more. Then run /ss-setup

in Claude Code or $ss-setup

in Codex (you can also choose it from Codex's /skills

picker). Your agent may ask you to approve tools on first use. No install possible? The rules alone still do the core work.

Your agent, its exact path:

Your agent Reads Fastest install
Claude Code
CLAUDE.md + /ss-* skills
npx skills add bitjaru/styleseed
Cursor
.cursorrules
cp engine/.cursorrules .cursorrules — or paste the prompt above
Codex
AGENTS.md + $ss-* skills (.agents/skills )
npx skills add bitjaru/styleseed
Amp · Gemini CLI
AGENTS.md + skills
npx skills add bitjaru/styleseed
Windsurf · Copilot · any other
the paste-prompt above no install — paste & go

More paths (manual copy, Cursor, awesome-design-md brands) in Install by hand below.

  • You asked Claude Code orCursor to build a dashboard and it came out amateur-looking - You're vibe coding a SaaS app and don't want to hire a designer - You use shadcn/ui but the output still feels generic - You want Toss-style refinement without reverse-engineering it yourself - You're building a Claude Code skill orCursor rules setup for design - You ship fast with AI and need professional UI that doesn't look AI-generated

There are lots of "help your AI design" projects now. Most solve a slice. StyleSeed is the one that targets the whole "looks AI-generated" problem — and enforces the fix.

StyleSeed | Brand / DESIGN.md collections | "Make-it-prettier" skills | UI generators (Claude Design, v0…) | | |---|---|---|---|---| Teaches design judgment (how designers think) | ✅ | ❌ data only | ❌ | | Fights the AI-look itself — default indigo, icon-chip cliché, template layouts, rainbow lists | ✅ | ❌ | ❌ | ❌ | Scored Quality Gate — reviews + fixes the UI before you see it | ✅ | ❌ | ❌ | ❌ | Anti-drift design lock — decisions persist across sessions | ✅ | ❌ | ❌ | ❌ | Works across every agent (Claude Code · Cursor · Codex · Amp · Gemini) | ✅ | ❌ one tool | || Brand skins + named motion system | ✅ | ❌ | || | Free & MIT | ✅ | ✅ | usually | freemium |

They're not all competitors — a DESIGN.md

gives StyleSeed a skin; a generator gives it a first draft. StyleSeed is the judgment + enforcement layer the others don't have.

The kind of specific, named calls a senior designer makes without thinking — written down so an AI applies them every time:

The refined black is— a 5-step grayscale ramp, never pure black#2A2A2A

, not#000

One accent, everything else greyscale— the single-accent law; a second hue is the fastest "un-designed" tell** Numbers 2:1 with their unit**— a 48px value over a 24px unit; equal sizes flatten magnitude into noise** Nested-radius law:**— concentric corners, so a card and its inner button agreeinner = outer − padding

Layered, low-opacity shadows (≤8%) lit from one direction— not one hard drop shadow** Tabular numbersfor anything that updates — no width jitter as values change Status color = severity only**— a "normal" row is grey; color marks the exception, never a rainbow list** No emoji icons, and no Lucide-in-a-pale-chip on every card**(§CC-9b) — the two opposite AI icon tells** 8px spatial grid; gap-around-a-group > gap-inside it**— proximity that reads as structure** Optical, not pixel, alignment**— nudge arrows/play glyphs; center type by cap-height** Desktop body ≥16px, one focal point per screen**— the tight mobile scale and an all-even grid both read "machine-made"** One radius personality · one icon set · one shadow language**— the coherence laws (§C0), the #1 fix for "looks AI-generated"** Motion scoped by surface**— a dashboard stays calm; a landing page gets theCinematic tier(scroll-linked reveals, 3D hero, animated gradients — the Stripe/Linear playbook). Scroll-jackingis still banned everywhere (§43)

See all 74 rules → · the craft & coherence laws →

Every "help LLMs design better" project solves the wrong half of the problem. They feed the model more design data — brand palettes, font specs, shadow tokens, component libraries. I tried that first. Dumped Toss's entire design token JSON into my prompts. The output was still generic.

Then it hit me: a junior designer with Toss's palette still ships ugly dashboards. A senior designer with only grayscale ships something refined. The difference isn't what they have. It's what they know to do with it.

Design data is the paint. Design judgment is knowing where to put it.

** See the before/after →** — the same dashboard brief, generated generically vs. with the 74 rules applied. Every fix annotated with the rule behind it.

StyleSeed is a design engine — 74 visual rules, 48 components, a named motion system, and 19 agent skills that teach LLMs the judgment, not just the data:

"The most refined black isn't #000 — it's #2A2A2A"
"One accent color in the entire app. Everything else grayscale. Restraint is elegance."
"Shadows at 4% opacity. If you can see it, it's already too much."
"Numbers and units at 2:1 ratio. 48px number, 24px unit. Always."
"Never repeat the same section type twice. Alternate tall and compact for rhythm."
"Card/background separation matters more than any border."

Nobody writes these down. They're baked into years of experience — invisible to outsiders, invisible to LLMs. StyleSeed writes them down, organizes them into six categories (color discipline, spatial rhythm, information hierarchy, shadow/elevation, component variance, motion/feedback), and hands them to Claude as a single markdown file it reads automatically.

The rules are brand-agnostic — they don't reference specific colors, only semantic tokens. Which means the same rulebook works whether your app looks like Toss, Vercel, or your client's weird purple brand. Swap the skin, the judgment carries over.

Claude Design generates UI fast — but it still picks #000

for text, reaches for six accent colors, and floats cards with no background separation. The missing piece isn't more templates. It's the 74 rules that tell the model when to use which pattern and why.

StyleSeed + Claude Design together:

  • Claude Design generates the layout and components (fast scaffolding)
  • StyleSeed's 74 rules refine the output (design judgment layer)
  • Brand skins make it look like your brand, not like "AI made this"

Drop DESIGN-LANGUAGE.md

into your Claude Design workflow and the same model produces noticeably more refined output — without changing a single prompt.

Use both — they solve different halves of the problem. Anthropic's official frontend-design skill scaffolds a clean screen fast, and it's a great starting point. StyleSeed is the layer

on top:

Official frontend-design | StyleSeed | | |---|---|---| | Gets you a coherent screen | ✅ | ✅ | | Names & bans the generic-AI tells | — | ✅ by name (default indigo, icon-chip, rainbow lists…) | | Scored gate that fixes before you see it | — | ✅ /ss-score loops to ≥80 | | Locks decisions so they don't drift across prompts | — | ✅ STYLESEED.md | | Presets + dials to move the whole look at once | — | ✅ /ss-restyle , /ss-dial |

Official gets you coherent. StyleSeed keeps you from looking templated. Run the official skill to scaffold, then let StyleSeed's gate refine and enforce.

The fastest paths are at the top — paste one prompt, or npx skills add bitjaru/styleseed

. To wire StyleSeed into an existing project manually, use one of the options below.

New to this? Read top to bottom — every step matters.The most common mistake is expecting setup to work before the skill is installed. Claude Code scans.claude/skills/

; Codex scans.agents/skills/

.

Step 1 — Install the skills. The portable path for every supported agent is:

npx skills add bitjaru/styleseed

For a manual project-local install, clone StyleSeed and copy the canonical skill folders into the path your agent scans:

git clone https://github.com/bitjaru/styleseed.git /tmp/styleseed

mkdir -p .claude/skills
cp -r /tmp/styleseed/engine/.claude/skills/* .claude/skills/

mkdir -p .agents/skills
cp -r /tmp/styleseed/engine/.claude/skills/* .agents/skills/

Step 2 — Start a fresh agent session, open your project, and invoke setup:

Claude Code: /ss-setup
Codex:       $ss-setup   # or open /skills and choose ss-setup

The wizard then walks you through:

  • App type (SaaS, e-commerce, fintech...)
  • Brand color or pick a skin (Toss, Stripe, Linear, Vercel, Notion...)
  • Or fetch any brand from awesome-design-md(58+ brands) - Font preference
  • Generates your first page automatically

Don't see the skills? For Claude Code, check

.claude/skills/

and use the/ss-

prefix. For Codex, check.agents/skills/

, open/skills

, or invoke$ss-setup

. Start a new session after installing if discovery looks stale.

Already did step 1 above? These commands copy the rest of the engine into a typical src/

-based React project. The source folder is engine/ (replace

/tmp/styleseed

with wherever you cloned it):

mkdir -p .claude
cp /tmp/styleseed/engine/DESIGN-LANGUAGE.md .claude/DESIGN-LANGUAGE.md
cp /tmp/styleseed/engine/CLAUDE.md          ./CLAUDE.md

mkdir -p src/styles src/components
cp -r /tmp/styleseed/engine/css/*        src/styles/
cp -r /tmp/styleseed/engine/components/*  src/components/

cp /tmp/styleseed/skins/stripe/theme.css src/styles/theme.css
Refer to https://github.com/bitjaru/styleseed — read engine/CLAUDE.md 
and engine/DESIGN-LANGUAGE.md, then build a SaaS dashboard.
Use skins/stripe/theme.css for the color palette.
cp engine/.cursorrules your-project/.cursorrules

Want just some skills? npx skills add bitjaru/styleseed --skill ss-motion,ss-page cherry-picks.

The honest reason: consistency comes from constraints. If you used a bare "apply StyleSeed" prompt (without the plan-mode + key-color + quality-gate steps the prompt above includes), the agent reads a summary once and improvises — so colors land at random and there's no key color. The reference demo (styleseed-demo.vercel.app) came out polished because it was built with the full rules in context and iterated with /ss-review

— not one-shot. Recreate those conditions:

Plan first. In Claude Code pressShift+ Tabto enterPlan Mode, then decide the design** one step at a time, with full context**, before any code is written. This is the single biggest fix.** Pin one key color.**Give the agent a brand hex — or pick a skin (Linear / Stripe / Toss / …). The rule is*one accent, everything else greyscale.*No key color = the "random colors" look.Point it at the full rules, not the summary:read https://styleseed-demo.vercel.app/llms-full.txt

(the shortllms.txt

is an index, not the 74 rules).Lock the decisions in a file. Run/ss-setup

(or just ask the agent to "write aSTYLESEED.md

design lock"). It records your skin, key color, radius, and motion inSTYLESEED.md

at the repo root, and the rules tell the agent toobey it on every prompt— so the design stops being "different every time." This is the single strongest fix for inconsistency. (Also installCLAUDE.md

/AGENTS.md

/.cursorrules

so the rules themselves are re-read every prompt.)Be specific:*"Build a dashboard in the Linear skin, one blue accent, Snap motion, following StyleSeed's rules"beats"build a dashboard."*Check & iterate. Run/ss-review

or/ss-score

, or tell it:"self-check coherence — one radius, one accent, real empty//error states — and fix violations."If it drifts:"re-read CLAUDE.md and fix the coherence violations."

More constraints = less variance.Plan mode + a pinned key color + installed rules + a review pass is the difference between "looks generated" and "looks designed."

StyleSeed isn't only for new screens — it's the design counterpart to a code review for UI you already shipped. If an earlier build looks coherent but generic (default indigo, tiny desktop text, the same Lucide-icon-in-a-pale-chip on every card, no focal point):

— grades the screen 0–100 and names the exact "AI-made" tells (default accent, icon-chip cliché, sub-16px body on desktop, no focal point, missing states)./ss-score src/…

— the design code-review: applies the fixes (retint to your key color, drop the chips, bump the type scale, create a focal point), then re-score to/ss-review src/…

≥80.— no design lock yet? It writes a/ss-update

→ RetrofitSTYLESEED.md

(mood, key color, font, surface) so the whole project stops drifting, then upgrades screen by screen.

The rules got stronger in v2.5.0, so a screen that passed the old bar may score lower now — that's the point. Fixing it is what makes it stop looking AI-made.

┌─────────────────────────────────────────────────┐
│  StyleSeed Engine (brand-agnostic)              │
│                                                 │
│  74 rules · 48 components · 19 skills · motion  │
│  Layout · Composition · Typography · UX · A11y  │
└──────────────────────┬──────────────────────────┘
                       │
              Pick a skin ↓
                       │
    ┌──────┬──────┬──────┬──────┬──────┬─────────┐
    │ Toss │Stripe│Linear│Vercel│Notion│ 58 more │
    │      │      │      │      │      │(awesome)│
    └──────┴──────┴──────┴──────┴──────┴─────────┘

Engine = how your app is structured (design intelligence)

  • 74 visual design rules (layout, composition, rhythm, forbidden patterns)
  • 48 React components (32 primitives + 16 patterns)
  • A named motion system (5 seeds + a copy-paste keyword library)
  • 19 cross-agent skills (setup, UI, motion, UX, accessibility)
  • Works with ANY color palette

Skin = what your app looks like (visual identity)

  • Just a theme.css

file with color variables - 7 built-in skins: Toss, Stripe, Linear, Notion, Raycast, Arc, Vercel

and you're done)

Data repos (awesome-design-md) = paint colors. StyleSeed = the rulebook for where to put the paint. Use them together: they provide the skin, StyleSeed provides the brain. (Full comparison in Where StyleSeed fits.)

Most AI-generated motion is the same default fade. StyleSeed gives motion a vocabulary — so you (and the LLM) can name a feel and get consistent, intentional animation across every page. Two layers:

1. Seeds = personality. Five named presets, each a spreadable framer-motion recipe in five contexts (entrance

/ exit

/ hover

/ press

/ layout

):

Seed Vibe Inspiration
Spring
bouncy, energetic, playful Arc, Toss
Silk
smooth, elegant, continuous Stripe, Linear
Snap
instant, decisive, precise Raycast, Linear
Float
weightless, gentle, dreamy Apple
Pulse
rhythmic, alive, punchy Discord, music apps
import { spring } from "@engine/motion";

<motion.button {...spring.hover} {...spring.press}>Save</motion.button>

2. Keywords = distinctive moves. A library of copy-paste named motions behind one handle — toggle-flip

, toggle-curtain

, reveal-blur

, pop-in

, tilt-3d

, magnetic

, glow-pulse

, confetti-pop

, shimmer

, and more. Say the keyword while vibe coding (or run /ss-motion toggle-flip

) and the same recipe lands in your code.

▶ ** Preview & copy every motion at the live gallery →** ·

Vibe-code your own → the motion guide

3. Motion is scoped by surface — calm apps, cinematic landing pages. This is the part most rule-sets get wrong: they ban scroll animation everywhere (so your marketing page ends up flat), or allow it everywhere (so your dashboard scroll-jacks). StyleSeed splits it:

Surface Motion posture
App / dashboard / data / forms
Calm. No scroll-jacking, no gimmick 3D, never animate a balance. The UI gets out of the way.
Marketing / landing / brand pages
Cinematic tier. Scroll-linked reveals, pinned/sticky sections, the "product assembles as you scroll" move, subtle parallax, a 3D/tilt hero, animated gradient/mesh or video backgrounds, rich hover — the family.co / stripe.com / linear.app playbook.

The line StyleSeed draws: scroll- linked (native scroll drives it, you stay in control) is encouraged on brand pages;

scroll-(hijacking scroll speed, trapping you) is banned everywhere. The Cinematic tier keeps its guardrails — 60fps (

jackingtransform

/opacity

only), never blocks the first read or the CTA, and prefers-reduced-motion

always leaves a complete static page. So you can build a Stripe-grade landing page anda calm dashboard from the same engine, each with the right restraint.

(Rules: DESIGN-LANGUAGE §43 · PAGE-TYPES → Landing)

All seeds auto-respect prefers-reduced-motion

, and the /ss-motion

skill pulls every recipe from one source of truth — so motion stays consistent no matter who (or what) writes the code.

Skin Style Source
Korean fintech — purple, minimal, data-focused Original
Professional — indigo, clean, multi-layer shadows awesome-design-md
Dark-first — violet, minimal, developer-focused awesome-design-md
Monochrome — black & white, geometric awesome-design-md
Warm — blue accent, friendly, warm neutrals awesome-design-md
Dark, punchy — red accent, snappy, launcher energy awesome-design-md
Playful — bold gradients, rounded, expressive awesome-design-md
58+ more
Any brand from

/ss-setup

— nothing vendored

engine/
├── CLAUDE.md                 # AI reads this automatically
├── AGENTS.md                 # Codex and other AGENTS.md-compatible agents
├── DESIGN-LANGUAGE.md        # 74 visual design rules (brand-agnostic)
├── .claude/skills/           # 19 canonical skills (Claude: /ss-*)
│   ├── ss-setup/             #   Interactive setup wizard
│   ├── ss-page/              #   Scaffold pages
│   ├── ss-component/         #   Generate components
│   ├── ss-pattern/           #   Compose layouts
│   ├── ss-motion/            #   Apply named motion (seeds + keywords)
│   ├── ss-review/            #   Design compliance check
│   ├── ss-tokens/            #   Manage tokens
│   ├── ss-a11y/              #   Accessibility audit
│   ├── ss-lint/              #   Quick violation scan
│   ├── ss-score/             #   Score UI 0-100 + fix list
│   ├── ss-update/            #   Pull latest engine
│   ├── ss-flow/              #   Design user flows
│   ├── ss-audit/             #   UX heuristic evaluation
│   ├── ss-copy/              #   Generate microcopy
│   └── ss-feedback/          #   Add /error/empty states
├── motion/                   # 5 motion seeds + keyword library
├── components/
│   ├── ui/                   # 32 primitives (shadcn/ui + motion)
│   └── patterns/             # 16 dashboard patterns
├── css/                      # base.css, fonts.css, index.css
├── tokens/                   # 6 JSON token files
├── utils/                    # Formatting utilities
├── icons/                    # Custom SVG icon library
└── scaffold/                 # Vite 6 + React 18 starter
Skill What It Does
/ss-build
The whole loop, enforced — lock the look → build → score → fix to ≥80 → then show. Use this instead of building UI free-hand
/ss-dial
Turn one axis up/down deterministically — density denser , radius sharper , color more-muted , weight bolder . Moves many tokens together, keeps the guardrails, re-gates
/ss-restyle
Re-style to a named aesthetic — swiss · editorial · technical · warm-dtc · minimal-mono · brutalist-lite . A coherent coordinate, not a stacked filter
/ss-setup
Interactive wizard — pick skin, brand color, font, generates first page
Skill What It Does
/ss-component
Generate components following design conventions
/ss-page
Scaffold pages with proper layout structure
/ss-pattern
Compose UI patterns (card grid, chart, list)
/ss-motion
Apply a named motion — a seed or a keyword move (toggle-flip , tilt-3d ...)
/ss-review
Audit code for design system violations
/ss-tokens
View, add, or modify design tokens
/ss-a11y
Accessibility audit (WCAG 2.2 AA)
/ss-lint
Quick automated lint — catches common violations in seconds
/ss-score
Score UI quality 0-100 with a category breakdown + prioritized fix list (reads the code)
/ss-verify
The visual gate — render the screen, screenshot it, score what you see (dead whitespace, unloaded fonts, no focal, blank empty states), fix + re-render
/ss-update
Pull latest engine updates — analyzes your project and updates safely
Skill What It Does
/ss-flow
Design user flows (progressive disclosure, information pyramid)
/ss-audit
Nielsen's 10 usability heuristics evaluation
/ss-copy
Generate UX microcopy (buttons, errors, empty states, toasts)
/ss-feedback
Add /success/error/empty states to any component
/ss-setup                    # Pick skin, configure project
/ss-page Dashboard           # Scaffold main page
/ss-copy "dashboard"         # Generate all microcopy
/ss-feedback src/Dashboard   # Add /error states
/ss-audit src/Dashboard      # Check UX quality
/ss-lint src/Dashboard       # Quick violation scan
/ss-review src/Dashboard     # Deep design compliance check
/ss-update                   # Pull latest engine updates

New project:

Refer to https://github.com/bitjaru/styleseed — read engine/CLAUDE.md 
and engine/DESIGN-LANGUAGE.md. Use skins/stripe/theme.css for colors.
Build a SaaS dashboard with revenue, users, and activity.

Add a page (engine already in project):

Follow CLAUDE.md and DESIGN-LANGUAGE.md rules.
Create a settings page with profile, notifications, and danger zone.
Run /ss-review when done.

Improve existing page:

Refactor src/Dashboard.tsx to follow DESIGN-LANGUAGE.md.
Check visual rhythm (rule 61) and KPI variation (rule 62).

Update engine:

/ss-update

React 18 · TypeScript · Tailwind CSS v4 · Radix UI · Vite 6 · Lucide Icons · CVA

StyleSeed shadcn/ui Tailwind UI Material UI Generic AI output
Components ✅ 48 ✅ 50+
Design judgment (when to use what)
✅ 74 rules Partial
Claude Code / Cursor integration ✅ 19 skills
Brand skins (Toss, Stripe, Linear...)
Price Free (MIT) Free $299+ Free
Works with AI coding tools
Indirect Indirect Indirect

TL;DR: shadcn/ui gives you components. Tailwind UI gives you templates. StyleSeed gives you the design judgment that makes AI output stop looking like AI output.

Q: Why does Claude Code / Cursor generate ugly UI? Because LLMs optimize for functional correctness, not visual refinement. They'll pick #000

for text, py-4

for spacing, text-xl

for everything — all technically valid, all amateur. StyleSeed gives them the rules professional designers use.

Q: Is this a shadcn/ui replacement? No — it's built on top of shadcn/ui patterns. StyleSeed components use the same Radix primitives and CVA conventions. Think of it as shadcn/ui + design judgment + AI-tool integration.

Q: Does it work with Cursor too? Yes. The 74 design rules live in a .cursorrules

file and CLAUDE.md

. Cursor reads them automatically.

Q: How is this different from awesome-design-md? awesome-design-md gives you brand DESIGN.md files (what). StyleSeed gives you the engine that turns any brand into a working app (how). They pair well.

Q: Can I use it for a non-fintech app? Yes. The engine is brand-agnostic. Pick any skin, swap the brand color, ship.

Full docs in the ** Wiki** — design rules reference, composition recipes, chart guides, skills reference.

StyleSeed is a living judgment framework — the rules aren't carved in stone. If you use it and find a pattern that reliably makes UI better, teach it to everyone's AI by proposing it as a rule.

A good rule is a decision + the reason it works, written so a model can apply it — not an opinion.

**Rule:** Numbers are 2:1 with their unit (a 48px value over a 24px unit).
**Why it works:** The eye locks onto magnitude first; equal sizes flatten the value into noise.
**Source:** Refactoring UI.

Open a ** "Propose a design rule"** issue, or PR it into

engine/DESIGN-LANGUAGE.md

(visual/layout) or engine/VISUAL-CRAFT.md

(craft & coherence). The judgment compounds as the community adds to it.Just a theme.css

  • skin.json

:

mkdir skins/your-brand
cp skins/toss/theme.css skins/your-brand/theme.css   # copy a skin as a starting point

Better rules → better AI output: more specific design rules, new pattern components, accessibility improvements, new AI skills.

See CONTRIBUTING.md for the full rule format and quality checklist.

Already using StyleSeed? Quick update (always safe):

cd styleseed && git pull

cp styleseed/engine/DESIGN-LANGUAGE.md your-project/.claude/DESIGN-LANGUAGE.md
cp -r styleseed/engine/.claude/skills/ your-project/.claude/skills/
mkdir -p your-project/.agents/skills
cp -r styleseed/engine/.claude/skills/* your-project/.agents/skills/

Don't overwrite: your theme.css

(brand colors), CLAUDE.md

(if project-specific), or customized components.

Full guide: engine/UPDATE.md

Get notified: Click WatchCustomReleases on this repo.

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