Designesy
MCP serverMediaThis integration scores any URL against a design contract and returns an A-F grade. It runs 40 checks, including validation of design tokens and motion. Once added, your AI can review the design quality of any web page on demand.
No key or account is asked for. Not verified by us yet: Ahel has not run a call through it.
Then ask your AI: use the designesy catalog tool from Designesy
Details
Available today. Use it as a step in a pipeline you build, or from your connected AI.
No key or account is asked for. Not verified by us yet: Ahel has not run a call through it.
After adding it, share a URL with your AI and ask it to score the page against your design contract.
What your AI can do with it
- Score any URL against a design contract
- Run 40 design checks on a page
- Get an A-F grade for a URL
- Validate design tokens
- Validate motion
Install Designesy
The server’s own address, for the clients that take one directly. Or connect Ahel once and every client you use reads it from one address, with the account kept on Ahel rather than in each client’s config.
Claude Code
claude mcp add --transport http --scope user designesy 'https://www.designesy.org/api/mcp'Run it once in your project, then open /mcp to approve any sign-in the server asks for.
Claude Desktop
https://www.designesy.org/api/mcpAdd a custom connector in Settings, paste this address, and approve the sign-in.
Cursor
cursor://anysphere.cursor-deeplink/mcp/install?name=designesy&config=eyJ1cmwiOiJodHRwczovL3d3dy5kZXNpZ25lc3kub3JnL2FwaS9tY3AifQ==Open the link and Cursor adds the server at that address.
ChatGPT
https://www.designesy.org/api/mcpIn Settings, enable Developer mode, create an MCP app, and paste this address. Your plan and workspace must allow custom apps.
Codex
codex mcp add designesy --url 'https://www.designesy.org/api/mcp'Run it once, then sign in with codex mcp login designesy if the server asks for an account.
From the project's README
As published by le-vai/designesy-org in README.md.
designesy.org — design-system contract verification, scoring, and review tools for AI agents.
Quick Start
Score any URL in 5 seconds — no install:
npx @designesy/score@latest https://your-site.com
Add to Claude Desktop, Cursor, or any MCP client:
# Remote (zero install, no auth):
claude mcp add designesy --transport http https://www.designesy.org/api/mcp
# Or local stdio via PyPI:
pip install designesy-mcp && designesy-mcp
Clone this repo? The .mcp.json at root auto-registers the server in Cursor and Claude Code — just open the project.
Gate your CI on design-contract compliance:
- uses: LE-VAI/designesy-org@v1
with:
url: https://your-app.vercel.app
min-score: 70
min-grade: B
post-comment: true # posts a summary comment on PRs (default)
The same 44-check engine powers an MCP server (17 tools for AI agents), a CLI with no required dependencies (npx @designesy/score), a GitHub Action, and a live leaderboard at designesy.org/leaderboard.
Designesy Contract Check is a GitHub Action that scores any URL against a 44-check design-system contract — tokens, motion, accessibility, cadence, takt, poise, identity, interaction, performance, responsive, semantic, security, spec, copywriting — and fails your CI workflow when the score or grade drops below your threshold. No LLM, no heuristics, no vibe-tax: every check is deterministic, reproducible, and grounded in a published contract.
Tools
designesy_score— Score a live URL against the 44-check design contract. Returns score, grade (A–F), and per-check breakdown.designesy_tokens_score— Validate a DTCG design-token file. 10 conformance checks against W3C DTCG 2025.10.designesy_a11y_score— Get the WCAG 2.2 AA accessibility framework and Playwright/axe-core script template.designesy_motion_score— Validate a Lottie animation file. 10 checks against Lottie spec v1.0.1 and §16 motion standards.designesy_contract— Get the design-system contract (tokens, motion, takt, cadence, typography, verification), whole or only the top-levelsectionsyou name.designesy_catalog— List the published Designesy packages with versions and URLs (the count comes back inpackage_count).designesy_design_review— Get the 8-dimension qualitative design review rubric.designesy_skill_md— Get the contract as an agent-skill-format SKILL.md for Cursor, Claude Code, or Replit.designesy_agent_json— Get the /.well-known/agent.json discovery document.designesy_llms_txt— Get the short /llms.txt agent brief.designesy_llms_full_txt— Get the full /llms-full.txt brief as reference data (its ingest steps and paste-ready agent prompt stay in the published file).
Tool reference table
| Tool | Description |
|---|---|
designesy_score | Score a live URL against the 44-check design contract — returns score, grade (A–F), per-check breakdown |
designesy_tokens_score | Validate a DTCG design-token file (10 conformance checks, W3C DTCG 2025.10) |
designesy_a11y_score | Get the WCAG 2.2 AA accessibility framework + Playwright/axe-core script template |
designesy_motion_score | Validate a Lottie animation file (10 checks, Lottie spec v1.0.1 + §16 motion standards) |
designesy_contract | Get the design-system contract (tokens, motion, takt, cadence, typography, verification), whole or only the top-level sections you name |
designesy_catalog | List the published Designesy packages with versions and URLs |
designesy_design_review | Get the 8-dimension qualitative design review rubric |
designesy_skill_md | Get the contract as an agent-skill-format SKILL.md (for Cursor/Claude Code/Replit) |
designesy_agent_json | Get the /.well-known/agent.json discovery document |
designesy_llms_txt | Get the short /llms.txt agent brief |
designesy_llms_full_txt | Get the full /llms-full.txt brief as reference data (its ingest steps and paste-ready agent prompt stay in the published file) |
Live
- Site: designesy.org
- MCP endpoint: designesy.org/api/mcp (Streamable HTTP, no auth)
- Score a site: designesy.org/score
- Leaderboard: designesy.org/leaderboard — 30 sites scored
- Methodology: designesy.org/methodology — full 44-check scoring methodology
- Contract: designesy.org/contracts/design-system
- Machine export: designesy.org/contracts/design-system.json
Contract verification
The live site is verified against the design system contract — 44 deterministic checks with provenance back to tokens. Both badges read the live leaderboard, which the weekly re-score refreshes, so the score here cannot drift from the engine; the per-check result is on the score page. See the methodology page for how the score is computed.
The contract
- 44 verification checks across 14 weighted categories — tokens, motion, accessibility, cadence, takt, poise, identity, interaction, performance, responsive, semantic, security, spec, copywriting
- Copywriting principles (added in v0.4.0) — 16 UX copy principles + 4 verification checks (button verb phrases, no trailing periods, descriptive link text, no ALL CAPS)
- 10 Non-Negotiable Motion Standards — deliberate easing, explicit properties, opacity entrances, keyboard stillness, no layout animation, touch gating, bounded duration, reduced-motion paths, asymmetric press, no ease-in
- 10 acoustic cues — custom
$type: sound(net-new vs W3C DTCG 2025.10), Cuelume v0.1.0 engine, interaction-only - 9 open tensions — documented, not hidden
- Spring physics — default + momentum tokens via custom
$type: spring - Machine-readable — W3C DTCG 2025.10 format + custom extensions
See the contract page for the full adoption history.
GitHub Action
Gate your CI on design-contract compliance:
- uses: LE-VAI/designesy-org@v1
with:
url: https://your-app.vercel.app
min-score: 70
min-grade: C
post-comment: true # posts a summary comment on PRs (default)
Scores a URL via the live /api/score engine and fails the workflow if the score or grade drops below your threshold. Runs on node24, posts PR comments via bare GitHub REST API (zero dependencies). See action/README.md for full usage.
CLI
Score a URL from the command line — for local development, pre-commit hooks, or scripts:
# Local (no install needed):
node cli/designesy-score.mjs designesy.org
# With gating (exit 1 on failure):
node cli/designesy-score.mjs linear.app --min-score 70 --min-grade B
# JSON output for piping:
node cli/designesy-score.mjs vercel.com --format canonical --json
# Via npm script:
npm run score -- designesy.org
Zero dependencies — Node built-ins only. The --api flag or SCORE_API env var overrides the scoring engine URL (defaults to https://www.designesy.org). See --help for all options.
Repository
This is the controlled public root for Designesy — a Next.js 15 App Router site (React 19, Turbopack, Vercel deploy).
apps/site Next.js application
action/ designesy/contract-check GitHub Action
cli/ designesy-score CLI
docs/designesy context, architecture, logs, registries
DESIGN.md the design contract (human-readable)
AGENTS.md agent operating rules
What Designesy is not
Designesy is not a template gallery. Designesy is not a generic AI design tool. Designesy is not a moodboard.
Designesy is a system.
Related tools
- Lyse — 258-check design system health scoring from your codebase (6 axes). Designesy scores any public URL; Lyse scores your repo. Complementary.
- DSAF — 125-criterion LLM-assisted design system maturity audit across 20 categories. Designesy is deterministic URL scoring; DSAF is LLM-assisted maturity assessment. Different layers, same goal.
- axe-core — WCAG accessibility testing. Designesy checks design-contract compliance (tokens, motion, typography) — a different layer. They complement each other.
- Lighthouse — Performance, accessibility, and SEO auditing. Designesy checks design-contract compliance — Lighthouse doesn't know what a design token is.
FAQ
Does it need an API key?
No. The MCP endpoint is stateless Streamable HTTP with no authentication. Sixteen of the 17 tools are read-only; designesy_monitor_score can send a drift-alert email to an address you pass.
Is it deterministic? Yes. There is no LLM in the scoring loop — every check is deterministic and reproducible. The same URL will always produce the same score.
What does it score against? The current Designesy design-system contract — 44 checks across 14 weighted categories (tokens, motion, accessibility, cadence, takt, poise, identity, interaction, performance, responsive, semantic, security, spec, copywriting).
Can I use it in CI? Yes. The GitHub Action gates your workflow on contract compliance — fail the build if the score drops below your threshold.
Where is the contract published? At designesy.org/contracts/design-system (human-readable) and designesy.org/contracts/design-system.json (machine-readable, W3C DTCG 2025.10).
License
MIT — see LICENSE. The contract is public; the code is open-source under MIT.
Tools it offers (17)
What this server listed when Ahel dialed its public endpoint in Oct 2026, with no key and no account of yours. The names are the server’s own.
designesy_catalogdesignesy_contractdesignesy_design_reviewdesignesy_skill_mddesignesy_agent_jsondesignesy_llms_txtdesignesy_llms_full_txtdesignesy_scoredesignesy_tokens_scoredesignesy_a11y_scoredesignesy_motion_scoredesignesy_drift_scoredesignesy_readiness_scoredesignesy_guardrailsdesignesy_monitor_scoredesignesy_comparedesignesy_report
Signals
- Last commit
- Oct 2026
Advanced
- Delivery
- designesy-org MCP server → your Ahel connector (mcp.ahel.ai) → your AI.
- Item type
- mcp-server
- Key
io-github-le-vai-designesy-org- Source
- github.com/le-vai/designesy-org
- Hosted endpoint
https://www.designesy.org/api/mcp
github.com/le-vai/designesy-org