MCP Server Tauri

# Tauri MCP Bridge Plugin [](https://crates.io/crates/tauri-plugin-mcp-bridge) [](https://www.npmjs.com/package/@hypothesi/tauri-plugin-mcp-bridge) [](https://docs.rs/tauri-plugin-mcp-bridge) [](https://github.com/hypothesi/mcp-server-tauri) A Tauri® plugin that bridges the Model Context Protocol (MCP) with Tauri applications, enabling deep inspection and interaction with Tauri's IPC layer, backend state, and window management. > **📦 This npm package is optional.** It provides TypeScript bindings for calling the plugin from your app's frontend code. If you're just using the [MCP Server for Tauri](https://github.com/hypothesi/mcp-server-tauri), you only need the **Rust crate** (`tauri-plugin-mcp-bridge`)—the MCP server communicates with it directly via WebSocket. ## Overview The MCP Bridge plugin extends MCP servers with direct access to Tauri internals. It provides real-time IPC monitoring, window state inspection, backend state access, and event emission capabilities. ## Installation ```bash cargo add tauri-plugin-mcp-bridge ``` Or add manually to your `src-tauri/Cargo.toml`: ```toml [dependencies] tauri-plugin-mcp-bridge = "0.2" ``` ### Optional: TypeScript Bindings If you want to call the plugin from your app's frontend code (not required for MCP server functionality): ```bash npm install --save-exact @hypothesi/tauri-plugin-mcp-bridge ``` ## Usage Register the plugin in your Tauri application: ```rust fn main() { let mut builder = tauri::Builder::default(); #[cfg(debug_assertions)] { builder = builder.plugin(tauri_plugin_mcp_bridge::init()); } builder .run(tauri::generate_context!()) .expect("error while running tauri application"); } ``` ### Custom Configuration By default, the plugin binds to `0.0.0.0` (all interfaces) to support remote device development. For localhost-only access: ```rust use tauri_plugin_mcp_bridge::Builder; fn main() { tauri::Builder::default() .plugin(Builder::new().bind_address("127.0.0.1").build()) .run(tauri::generate_context!()) .expect("error while running tauri application"); } ``` ## Features ### 1. IPC Monitoring Monitor all Tauri IPC calls in real-time with timing and argument capture: ```typescript // Start monitoring await invoke('plugin:mcp-bridge|start_ipc_monitor'); // Execute some commands to generate IPC traffic await invoke('greet', { name: 'World' }); // Get captured events const events = await invoke('plugin:mcp-bridge|get_ipc_events'); ``` ### 2. Window Information Get detailed window state: ```typescript const windowInfo = await invoke('plugin:mcp-bridge|get_window_info'); // Returns: { width, height, x, y, title, focused, visible } ``` ### 3. Backend State Inspect application backend state: ```typescript const state = await invoke('plugin:mcp-bridge|get_backend_state'); // Returns: { app: { name, identifier, version }, tauri: { version }, // environment: { debug, os, arch, family }, windows: [...], timestamp } ``` ### 4. Event Emission Trigger custom events for testing: ```typescript await invoke('plugin:mcp-bridge|emit_event', { eventName: 'custom-event', payload: { data: 'test' } }); ``` ## MCP Server Integration This plugin is part of the larger MCP Server for Tauri, which provides **16 total MCP tools** for comprehensive Tauri development and testing. The plugin specifically enables the following tools: ### Mobile Development Tools (1) 1. **tauri_list_devices** - List connected Android devices and iOS simulators ### UI Automation & WebView Tools (10) Tools for UI automation and webview interaction via the plugin's WebSocket connection: 1. **tauri_driver_session** - Manage automation session (start, stop, or status) 2. **tauri_manage_window** - List windows, get window info, or resize windows 3. **tauri_webview_find_element** - Find an element in the webview 4. **tauri_read_logs** - Read logs (console, Android logcat, iOS, system) 5. **tauri_webview_interact** - Perform gestures (click, double-click, long-press, swipe, scroll, focus) 6. **tauri_webview_screenshot** - Take screenshots of the entire webview 7. **tauri_webview_keyboard** - Type text or simulate keyboard events with optional modifiers 8. **tauri_webview_wait_for** - Wait for element selectors, text content, or IPC events 9. **tauri_webview_get_styles** - Get computed CSS styles for element(s) 10. **tauri_webview_execute_js** - Execute arbitrary JavaScript code in the webview context ### IPC Tools (5) Tools that directly use the MCP Bridge plugin's Rust backend: 1. **tauri_ipc_execute_command** - Execute any Tauri IPC command 2. **tauri_ipc_monitor** - Manage IPC monitoring (start or stop) 3. **tauri_ipc_get_captured** - Retrieve captured IPC traffic with optional filtering 4. **tauri_ipc_emit_event** - Emit custom Tauri events for testing event handlers 5. **tauri_ipc_get_backend_state** - Get backend application state and metadata ## Architecture ```text MCP Server (Node.js) │ ├── Native IPC (via plugin) ────> Tauri App Webview (DOM/UI) │ │ └── Plugin Client ──────────────────────┼──> Plugin Commands (WebSocket port 9223) │ │ mcp-bridge Plugin (Rust Backend) ``` ## WebSocket Communication The plugin runs a WebSocket server on port 9223 (or next available in range 9223-9322) for real-time communication with the MCP server. ### Remote Device Development By default, the WebSocket server binds to `0.0.0.0` (all network interfaces), enabling connections from: - **iOS devices** on the same network - **Android devices** on the same network or via `adb reverse` - **Emulators/Simulators** via localhost #### Connecting from MCP Server The MCP server supports connecting to remote Tauri apps via the `tauri_driver_session` tool: ```typescript // Connect to a Tauri app on a remote device tauri_driver_session({ action: 'start', host: '192.168.1.100' }) // Or use environment variables: // MCP_BRIDGE_HOST=192.168.1.100 npx mcp-server-tauri // TAURI_DEV_HOST=192.168.1.100 npx mcp-server-tauri (same as Tauri CLI uses) ``` #### Connection Strategy The MCP server uses a fallback strategy: 1. Try `localhost:{port}` first (most reliable for simulators/emulators/desktop) 2. If localhost fails and a remote host is configured, try `{host}:{port}` 3. Auto-discover apps on localhost if specific connection fails ## Development ### Building the Plugin From the plugin directory: ```bash cd packages/tauri-plugin-mcp-bridge cargo build ``` Or from the workspace root: ```bash npm run build:plugin ``` ### Documentation View the comprehensive Rust API documentation: ```bash npm run docs:rust ``` Or directly: ```bash cd packages/tauri-plugin-mcp-bridge cargo doc --open --no-deps ``` ### Testing Run the MCP server tests which include plugin integration tests: ```bash npm test ``` ## Permissions Add the plugin's default permission to your Tauri capabilities file (`src-tauri/capabilities/default.json`): ```json { "permissions": [ "mcp-bridge:default" ] } ``` This grants all permissions required by the MCP server. The plugin is designed to work as a complete unit—partial permissions are not recommended as the MCP server expects all commands to be available. ## API Documentation For detailed API documentation, including: - Complete function signatures and parameters - Rust examples for backend integration - TypeScript examples for frontend usage - Architecture and design details Visit the [docs.rs documentation](https://docs.rs/tauri-plugin-mcp-bridge) or build locally with `npm run docs:rust`. ## License MIT © [hypothesi](https://github.com/hypothesi) --- ## Trademark Notice TAURI® is a registered trademark of The Tauri Programme within the Commons Conservancy. [https://tauri.app/](https://tauri.app/) This project is not affiliated with, endorsed by, or sponsored by The Tauri Programme within the Commons Conservancy.