stitch-mcp-stdio

Stable stdio MCP server for Google Stitch AI UI design tool.

Drop-in replacement for @_davideast/stitch-mcp that eliminates the proxy layer crash (libuv UV_HANDLE_CLOSING assertion failure on Windows and intermittent connection drops on other platforms).

Why this exists

The official @_davideast/stitch-mcp package runs a proxy subprocess that suffers from a libuv bug causing random crashes, especially on Windows. This package uses the same @google/stitch-sdk under the hood but connects via stdio transport directly -- no proxy process, no crash.

Setup

1. Get a Stitch API key

Go to stitch.withgoogle.com -> Profile -> Settings -> API Key.

2. Configure your MCP client

Point any MCP-compatible client (Claude Code, Claude Desktop, Cursor, Gemini CLI, VS Code) at npx stitch-mcp-stdio:

{
  "mcpServers": {
    "stitch": {
      "command": "npx",
      "args": ["-y", "stitch-mcp-stdio"],
      "env": {
        "STITCH_API_KEY": "your-api-key"
      }
    }
  }
}

npx -y downloads + runs the latest version without a permanent install. To pin a version use stitch-mcp-stdio@1.0.0.

Alternative: local clone (if you'd rather not use npx)

git clone https://github.com/bluedevilcollectibles/stitch-mcp-stdio.git
cd stitch-mcp-stdio
npm install

Then point the client at node /path/to/stitch-mcp-stdio/server.js instead of npx.

Available tools

All 12 tools from the Stitch SDK are exposed:

Tool	Description
create_project	Create a new Stitch project
get_project	Get project details
list_projects	List all projects
list_screens	List screens in a project
get_screen	Get screen details
generate_screen_from_text	Generate a screen from a text prompt
edit_screens	Edit an existing screen
generate_variants	Generate design variants
create_design_system	Create a design system
update_design_system	Update a design system
list_design_systems	List design systems
apply_design_system	Apply a design system to screens

How it works

MCP Client (Claude, Cursor, etc.)
    |
    | stdio (stdin/stdout)
    |
stitch-mcp-stdio (this package)
    |
    | HTTPS (API key auth)
    |
stitch.googleapis.com/mcp

No proxy subprocess. No libuv handle management. Just stdio in, API calls out.

Built by

Blue Devil Collectibles -- makers of LiveSeller Pro, inventory and live selling tools for comic shops, card shops, and collectibles dealers.

We built this MCP server to power our AI design pipeline. If you sell on WhatNot, manage pull lists, or run a brick-and-mortar shop, check out what we're building.

License

MIT