tauri-mcp-bridge

name	tauri-mcp-bridge
description	MCP Bridge setup and tool reference for Tauri v2 apps. Use when setting up MCP Bridge plugin, troubleshooting connection issues, or looking up which MCP tool to use for UI automation tasks (screenshots, DOM inspection, element interaction, backend state queries).

Tauri MCP Bridge

Reference for MCP Bridge plugin setup and tool usage in Tauri v2 apps.

Setup Checklist

Run scripts/check-setup.sh to verify setup, or check manually:

Requirement	File	What to Check
Dependency	src-tauri/Cargo.toml	tauri-plugin-mcp-bridge = "0.8"
Plugin registration	src-tauri/src/lib.rs	builder.plugin(tauri_plugin_mcp_bridge::init()) in #[cfg(debug_assertions)]
Global Tauri	src-tauri/tauri.conf.json	"withGlobalTauri": true in app section
Permission	src-tauri/capabilities/default.json	"mcp-bridge:default" in permissions array
VS Code config	.vscode/mcp.json	Server configured for @hypothesi/tauri-mcp-server

Connection Workflow

1. Start app: npm run tauri dev
2. Wait ~10s for WebSocket server (port 9223)
3. driver_session(action="start")
4. driver_session(action="status") → verify connected=true

Tool Catalog

Session Management

Tool	Purpose
driver_session	Start/stop/status of MCP connection

UI Inspection

Tool	Purpose
webview_screenshot	Capture current UI as image
webview_dom_snapshot	Get full element tree
webview_find_element	Locate elements by CSS selector
webview_get_styles	Get computed styles of element

UI Interaction

Tool	Purpose
webview_interact	Click, focus, select, scroll
webview_keyboard	Type text, press keys
webview_wait_for	Wait for element/condition

Backend Integration

Tool	Purpose
ipc_get_backend_state	Query Rust state (e.g., StateMachine)
ipc_execute_command	Call Tauri commands directly
ipc_emit_event	Emit events to frontend
ipc_get_captured	Get captured IPC traffic
ipc_monitor	Monitor IPC calls in real-time

Window Management

Tool	Purpose
manage_window	Move, resize, focus windows
list_devices	List available input devices

Logs

Tool	Purpose
read_logs	Read Tauri app logs

Troubleshooting

Connection Fails

1. App not running: Start with npm run tauri dev, wait for window
2. Wrong port: WebSocket binds to 9223 by default
3. Missing globalTauri: Add "withGlobalTauri": true to tauri.conf.json
4. Missing permission: Add "mcp-bridge:default" to capabilities
5. Plugin not registered: Check lib.rs has plugin init in debug block
6. Port in use: Kill other processes on 9223, or configure different port

Element Not Found

1. Check selector syntax (CSS selectors)
2. Use webview_dom_snapshot to see actual element tree
3. Element may not be rendered yet—use webview_wait_for
4. Element may be in shadow DOM or iframe

Backend State Empty

1. Verify state is exposed via Tauri command
2. Check command is registered in generate_handler![]
3. Use ipc_execute_command to call get_state or similar

Common Patterns

Verify Button Exists and Works

1. webview_find_element(selector="button.start-btn")
2. Verify: element found
3. webview_interact(action="click", selector="button.start-btn")
4. webview_screenshot() → capture result
5. ipc_get_backend_state() → verify state changed

Wait for Async Operation

1. webview_interact(action="click", selector="#submit")
2. webview_wait_for(selector=".success-message", timeout=5000)
3. webview_screenshot() → capture final state

Capture Full UI State

1. webview_screenshot() → visual state
2. webview_dom_snapshot() → element tree
3. ipc_get_backend_state() → Rust state