Now in public beta

OpenAPI for AI-generated UI

A structured schema and design intelligence layer that makes AI coding assistants generate better, more consistent web applications. We don't care what you build with. We care what you build.

mcp.json
{
  "mcpServers": {
    "decantr": {
      "command": "npx",
      "args": ["-y", "@decantr/mcp-server"]
    }
  }
}

Design intelligence, not code generation

Decantr tells your AI assistant how to build — the structure, the patterns, the constraints — so the output is consistent every single time.

Structured Design Schema

Like OpenAPI but for UI. Define your design system, layout patterns, and visual recipes in a single machine-readable spec.

AI-Native Design Intelligence

Feed your Essence spec to Claude, Cursor, or Copilot via the MCP server. They generate consistent, on-brand UI every time.

Guard Against Drift

Built-in guard rules validate every code change against your spec. Prevent style drift, layout violations, and accessibility regressions.

Pattern Registry

Browse curated patterns, themes, shells, and recipes. Compose them into full application blueprints with a single command.

How it works

Three steps from intent to guarded, production-quality UI.

01

Define

Describe your app. Decantr creates a structured Essence spec capturing your theme, layout, patterns, and guard rules.

02

Compose

The design pipeline resolves patterns, recipes, and shells into a full composition. Your AI assistant reads it via MCP.

03

Generate & Guard

Your AI generates consistent, production-quality code. Guard rules validate every change against the spec. No drift.

Simple, transparent pricing

Start free. Upgrade when you need private namespaces, team features, or priority support.

Free

$0forever

For individual developers and experimentation.

  • All open-source packages
  • Public registry access
  • Community patterns & themes
  • CLI + MCP server
  • Up to 3 projects
Most Popular

Pro

$29/month

For professional developers shipping real products.

  • Everything in Free
  • Unlimited projects
  • Private registry namespaces
  • Priority content updates
  • Advanced guard analytics
  • Email support

Team

$99/month

For teams that need shared design intelligence.

  • Everything in Pro
  • Up to 10 team members
  • Shared Essence specs
  • Team pattern library
  • SSO + role management
  • Dedicated support

Set up in 30 seconds

Install the CLI, initialize your project, and connect the MCP server to your AI assistant.

1. Install the CLI

npm install -g decantr

2. Initialize your project

decantr init

3. Add MCP server to your assistant

// Add to your mcp.json or claude_desktop_config.json
{
  "mcpServers": {
    "decantr": {
      "command": "npx",
      "args": ["-y", "@decantr/mcp-server"]
    }
  }
}

Ready to make your AI build better?

Join the beta. Define your design system once, and let your AI assistant generate consistent UI every time.