tauri-plugin-mcp

Cross-platform Tauri test automation plugin via MCP (Model Context Protocol).

Enables AI assistants like Claude to interact with your Tauri desktop app for testing and automation.

Features

• Cross-platform: Windows (Named Pipes) + macOS/Linux (Unix Sockets)
• No CDP dependency: Works on all WebView backends including macOS WKWebView
• MCP integration: Direct integration with Claude Code and other MCP clients

Prerequisites

• Node.js >= 18
• Tauri v2.x
• pnpm (recommended) or npm
• Rust with cargo

Quick Start

1. Add Rust plugin to src-tauri/Cargo.toml
2. Install npm package: pnpm add github:DaveDev42/tauri-plugin-mcp#main
3. Register plugin in src-tauri/src/lib.rs
4. Add mcp:default permission
5. Initialize bridge in main.tsx
6. Create .mcp.json for Claude Code

Installation

1. Rust Plugin (src-tauri/Cargo.toml)

[dependencies]
tauri-plugin-mcp = { git = "https://github.com/DaveDev42/tauri-plugin-mcp" }

2. Frontend API (package.json)

pnpm add github:DaveDev42/tauri-plugin-mcp#main

3. MCP Server

The MCP server is included in the package at:

node_modules/tauri-plugin-mcp/packages/tauri-mcp/dist/index.js

Setup

1. Register the plugin (src-tauri/src/lib.rs)

pub fn run() {
    tauri::Builder::default()
        .plugin(tauri_plugin_mcp::init())
        .run(tauri::generate_context!())
        .expect("error while running tauri application");
}

2. Add permissions

Option A: In tauri.conf.json or config/*.json5 (recommended)

{
  "security": {
    "capabilities": [{
      "identifier": "main-capability",
      "windows": ["main"],
      "permissions": ["core:default", "mcp:default"]
    }]
  }
}

Option B: Separate file (src-tauri/capabilities/default.json)

{
  "$schema": "../gen/schemas/desktop-schema.json",
  "identifier": "default",
  "windows": ["main"],
  "permissions": ["core:default", "mcp:default"]
}

3. Initialize the bridge (main.tsx)

// Initialize MCP bridge for E2E testing (dev mode only)
if (import.meta.env.DEV) {
  import('tauri-plugin-mcp').then(({ initMcpBridge }) => {
    initMcpBridge().catch(err => {
      console.warn('[MCP] Bridge initialization failed:', err);
    });
  });
}

MCP Server Configuration

Add to .mcp.json in your project root:

{
  "mcpServers": {
    "tauri-mcp": {
      "command": "node",
      "args": ["node_modules/tauri-plugin-mcp/packages/tauri-mcp/dist/index.js"],
      "env": {
        "TAURI_PROJECT_ROOT": "."
      }
    }
  }
}

Available Tools

Using features parameter

To launch with Cargo features:

launch_app({ features: ["my_feature"] })

This runs: pnpm tauri dev --features my_feature

Usage Example

Typical testing workflow:

1. launch_app({ timeout_secs: 120 })
2. snapshot()           # Get element refs
3. click({ ref: 5 })    # Click button by ref
4. fill({ selector: "input[name='email']", value: "test@example.com" })
5. screenshot()         # Verify result
6. stop_app()

How It Works

Claude Code <-> MCP Server <-> Socket <-> Tauri Plugin <-> JS Bridge <-> Your App

1. Rust Plugin creates IPC server (Unix socket or Windows named pipe)
2. MCP Server connects to IPC and exposes tools to Claude
3. JS Bridge (initMcpBridge()) enables DOM operations in WebView

Socket Paths

• Unix: {project_root}/.tauri-mcp.sock
• Windows: \\.\pipe\tauri-mcp-{hash} (hash derived from project path)

Troubleshooting

"MCP bridge not initialized"

The JS bridge isn't running. Check:

• initMcpBridge() is called in your frontend code
• App is running in dev mode (import.meta.env.DEV)
• Check browser console for initialization errors

Socket connection failed

• Ensure the app is running (launch_app first)
• On Windows, check pipe path in logs: [tauri-plugin-mcp] full_path: \\.\pipe\tauri-mcp-XXXXX
• On Unix, check if .tauri-mcp.sock exists in project root

App launch timeout

• Increase timeout_secs (default: 60)
• Check if pnpm tauri dev works manually
• Look for build errors in terminal output

snapshot returns empty

• Wait for app to fully load (use wait_for_ready: true)
• Check if bridge initialized (look for [MCP] logs in console)

License

MIT OR Apache-2.0