ui-craft MCP Server

Deterministic design-quality gate exposed as a stdio MCP server. Complements the ui-craft skill (taste/judgment layer) — never duplicates it.

Install

npm install -g ui-craft-mcp
# or use npx (no install required):
npx ui-craft-mcp

Wiring

Copy .mcp.json.example from the repo root to .mcp.json in your project:

{
  "mcpServers": {
    "ui-craft": {
      "command": "npx",
      "args": ["ui-craft-mcp"]
    }
  }
}

Claude Desktop, Cursor, and other MCP clients read .mcp.json automatically.

Tools

check_anti_slop

Scans source code for anti-slop violations using the 38 deterministic rules from ui-craft-detect. In-process (no subprocess spawn).

Input (one required):

• code — inline source string
• path — file or directory path

Output:

{
  "findings": [{ "severity": "error|warning", "rule": "...", "file": "...", "line": 42, "message": "..." }],
  "summary": { "total": 3, "errors": 2, "warnings": 1 }
}

tokens_lint

Static regex analysis for off-system token values. Flags: raw hex colors, non-scale border-radius px, non-8pt spacing px, and magic z-index integers. Token scale source: references/tokens.md.

Rule IDs: tokens/color, tokens/radius, tokens/spacing, tokens/z-index.

Input (one required): code or path

Output: same findings[] + summary shape as check_anti_slop.

acceptance_bar

Returns the deterministic acceptance checklist for a UI surface. Data only — no scoring or judgment. Scoring is the caller's responsibility using check_anti_slop + tokens_lint results.

Input:

• surface — one of: dashboard, landing, auth, generic

Output:

{
  "surface": "dashboard",
  "items": [{ "id": "dash-01", "description": "...", "category": "hierarchy" }]
}

Surfaces:

• dashboard — SaaS dashboard acceptance bar (from recipe-dashboard.md)
• landing — Landing page acceptance bar (from recipe-landing.md)
• auth — Auth screen acceptance bar (from recipe-auth.md)
• generic — 10 finish-bar passes (from finish-bar.md)

Boundary: Taste vs. Deterministic

The MCP server is the checks layer. The SKILL.md is the taste layer.

This server contains ZERO taste, judgment, or aesthetic preference rules. All such rules live exclusively in skills/ui-craft/SKILL.md. The server produces identical output for identical input — it is a deterministic gate, not an AI evaluator.

acceptance-data — Regen on Recipe Edit

src/acceptance-data.mjs is hand-derived from the recipe and finish-bar reference files. It must be updated manually when any of these files change:

• references/recipe-dashboard.md — ## Acceptance bar section
• references/recipe-landing.md — ## Acceptance bar section
• references/recipe-auth.md — ## Acceptance bar section
• references/finish-bar.md — 10 pass descriptions

v1 is manual — no generator script. A generator is deferred. When updating: edit src/acceptance-data.mjs directly (an ESM module, export default { … }), following the existing { id, description, category } schema. It's a module rather than JSON so it inlines into the published bundle and loads from source on every Node version.

Development

cd mcp
npm install
npm test        # node --test (zero external deps)
node src/server.mjs  # run server directly

Node Version

Requires Node.js >= 18.