UI Preset MCP Server

MCP server for auto-configuring React UI against a swappable glassmorphic preset system. Integrates with your Monaco IDE to enforce design uniformity across all business builds.

Architecture

ui-preset-mcp-server/
├── src/
│   ├── index.ts                    # Server entry point (stdio + HTTP transports)
│   ├── constants.ts                # Shared constants and paths
│   ├── types/
│   │   └── index.ts                # All TypeScript types (tokens, presets, corrections)
│   ├── schemas/
│   │   └── toolSchemas.ts          # Zod validation schemas for every tool
│   ├── services/
│   │   ├── presetLoader.ts         # Reads + deep-merges preset files with caching
│   │   ├── sessionState.ts         # Active preset session management + overrides
│   │   ├── uiCorrector.ts          # AST correction engine (10 correction passes)
│   │   ├── tokenResolver.ts        # Resolves {{token:x.y.z}} placeholders + export generators
│   │   └── fileWatcher.ts          # Hot-reload presets on disk changes (dev mode)
│   └── tools/
│       ├── presetTools.ts          # load_preset, swap_template, list_presets, diff_presets, scaffold_preset
│       └── correctionTools.ts      # autocorrect_component, validate_ui, generate_component, generate_tokens, apply_token_overrides
└── presets/
    ├── glassmorphic-base/          # Core preset (all others inherit from this)
    │   ├── manifest.json
    │   ├── tokens.json             # Full design token system
    │   ├── components/
    │   │   ├── shell/Sidebar.json
    │   │   ├── surfaces/GlassCard.json
    │   │   ├── settings/OptionGroup.json
    │   │   └── navigation/NavGroup.json
    │   └── layouts/DashboardLayout.json
    ├── client-fintech/             # Blue accent, dense spacing
    ├── client-saas/                # Purple accent, wider cards
    └── client-dark-minimal/        # Monochrome, reduced glass intensity

MCP Tools

Preset Management

Correction & Generation

Installation

npm install
npm run build

Usage

stdio (for Monaco IDE integration)

node dist/index.js

HTTP server

TRANSPORT=http PORT=3001 node dist/index.js

Dev mode with hot-reload

WATCH_PRESETS=true node dist/index.js

Typical Workflow

1. load_preset("glassmorphic-base")          # Activate base preset
2. autocorrect_component(code)               # Fix component on save
3. validate_ui(code)                         # Get conformance score
4. generate_tokens({ format: "css" })        # Export CSS variables
5. swap_template("client-fintech")           # Switch to client variant
6. scaffold_preset({ preset_id: "client-x" })# Create new client preset

Creating New Presets

New presets only need to override tokens that differ from the parent:

// presets/client-newbrand/tokens.json
{
  "colors": {
    "accent": {
      "primary": "#e11d48"
    }
  }
}

// presets/client-newbrand/manifest.json
{
  "id": "client-newbrand",
  "name": "New Brand",
  "extends": "glassmorphic-base",
  "version": "1.0.0",
  "tags": ["custom"],
  "components": [],
  "layouts": []
}

All base tokens, components, and layouts are inherited automatically.

Correction Rules

The correction engine enforces these rules on every component:

• no-hardcoded-colors (error): All color values must use CSS custom properties
• no-hardcoded-spacing (warning): Spacing should use the token scale
• enforce-glass-surface (error): Surface elements must have backdropFilter + semi-transparent bg
• no-hardcoded-font-family (error): Font families must use typography tokens
• use-animation-tokens (warning): Transitions must use animation tokens
• enforce-sidebar-components (error): Sidebar content must use NavGroup/NavItem
• enforce-settings-components (error): Settings UI must use OptionGroup/OptionRow
• a11y-img-alt (warning): Images must have alt attributes
• a11y-icon-button-label (warning): Icon buttons need aria-label

Monaco Integration

In your Monaco editor, call autocorrect_component on the save event:

editor.onDidSaveModel(async () => {
  const code = editor.getValue();
  const result = await mcpClient.callTool('autocorrect_component', {
    code,
    context: 'auto',
    dry_run: false
  });
  if (result.corrected !== code) {
    editor.setValue(result.corrected);
  }
});