Computer Use

Computer Use runs through the standalone Node REPL MCP server. Its first js call loads global cua and displays documentation for the current platform. Computer Use and Browser Use no longer require bundled skills.

Qwen Code / any MCP client
  -> @qwen-code/node-repl-mcp (js, js_reset)
  -> @qwen-code/cua-sdk/runtime
     -> native Qwen CUA Driver (desktop applications)
     -> @qwen-code/browser-use (Qwen browser extension)

Setup

Node.js 22 or later and npm are required. Register the MCP server, then restart Qwen Code:

qwen mcp add --scope user node-repl npx -y @qwen-code/node-repl-mcp@0.26.0

The server installs the matching SDK and browser SDK as dependencies. The native SDK payload is downloaded for the current platform and verified against the matching release’s SHA-256 checksums. It is cached outside the npm package; no workspace SDK bootstrap command is needed. Version 0.26.0 is a local development target until its release is published.

Windows uses ordinary input delivery by default and does not install a UIAccess worker. Opting into UIAccess with CUA_DRIVER_USE_UIACCESS=1 requires a signed worker under Program Files\Qwen\CuaDriver; install the SDK from an elevated terminal with that variable set. An unsigned worker cannot enable UIAccess; do not bypass the signature check. Older unsigned releases need a new signed driver release for UIAccess, not a reinstall of the same version.

Application tasks

var app = await cua.getApp('Microsoft Excel');
// Use a short ID from the automatically displayed AX state.
await app.click(37);
await app.typeText('hello');
await app.getAXState();

getApp displays full AX text without an image. getAXState displays subsequent diffs. getScreenshot captures only the current window; getAXStateAndScreenshot captures both. Observations return strings and display themselves; {emit:false} suppresses output. Request a screenshot before using {x,y} coordinates, which are pixels in that window’s current screenshot.

The driver resolves applications/windows, owns current short IDs and coordinates, and chooses input delivery. macOS uses accessibility and directed events. Windows and Linux try background delivery first and use foreground input only after a refusal that proves nothing was sent. Foreground input stops when physical user activity is detected; it restores the prior application only if the user has not switched elsewhere. A dispatch acknowledgement does not prove the UI changed: observe before retrying.

Linux supports X11, including X11 applications under XWayland. Native Wayland applications are unsupported. Pass DISPLAY, XAUTHORITY and the desktop accessibility session bus to the server.

Desktop and browser tasks

Use the explicit desktop interface for full-screen tasks:

await cua.desktop.getScreenshot();
await cua.desktop.click({ x: 300, y: 200 }, { key: 'shift' });

Desktop coordinates are pixels in the latest primary-display screenshot. Desktop input controls the visible foreground desktop and can move the real pointer. For held keys, always use try/finally with cua.desktop.keyDown(key) and keyUp(key). Held keys belong to the calling session and are released on graceful reset/end. While holding keys, use keyDown/keyUp for chords and desktop pointer actions without explicit modifiers; release them before text, ordinary shortcuts or application input. Abrupt OS process termination cannot guarantee cleanup.

var browser = await cua.getBrowser('Chrome');
// Browser documentation and tabs are displayed on first selection.
var tab = await cua.getTab('TAB_ID', { browser: 'Chrome' });
await tab.playwright.domSnapshot();

getBrowser, getTab, and createBrowserTab return the existing repository browser-use SDK handles. Follow the selected browser’s runtime documentation and connect the Qwen browser extension as before. The integration adds no browser windows API, DOM diff or new Windows support.

Permissions and lifecycle

The server executes JavaScript with ordinary Node.js permissions and follows the client’s MCP approval flow. On macOS, Accessibility is required for input/AX observation and Screen Recording for screenshots; Automation may be requested for document save/Finder rename. Grants belong to the host process’s OS responsibility chain. On Windows, the normal installed daemon uses the existing UAC/logon-task path; applications it launches use a token derived from its own token at normal-user integrity. UIAccess is optional: explicitly setting CUA_DRIVER_USE_UIACCESS=1 requires a trusted signed worker under Program Files and fails if unavailable. Default npm installation does not stage that worker or require its signature.

js completes in one call and defaults to a 30-second timeout. A timeout can leave external effects; observe before retrying. js_reset discards bindings and gracefully closes the owning native/browser session. After context compaction call cua.rewriteDocumentation() before continuing.

Remote desktop relay

For an existing macOS desktop relay setup, install its matching server:

npx -y @qwen-code/node-repl-mcp@0.26.0 desktop-relay install

This uses the existing local launchd socket at 127.0.0.1:47821. In a secure Web Shell, choose Use this computer, then Connect this computer. The desktop prompts for each connection. The remote daemon must enable QWEN_SERVE_CLIENT_MCP_OVER_WS=1.

Direct MCP and troubleshooting

qwen-cua-driver mcp exposes the same 19 native Computer Use operations directly. App calls use app; desktop-capable calls use scope:"desktop" instead. key_down/key_up are desktop-only. Advanced native tools remain available through the host opt-in CUA_DRIVER_EXTRA_TOOLS=1.

If the server is unavailable, check qwen mcp list and restart the client after adding it. If capture fails, check the current desktop session and OS permissions. If native download fails, check the exact release version/checksum asset or supply a locally built matching payload through QWEN_CUA_SDK_NATIVE_DIR. A locked desktop cannot provide GUI acceptance evidence.

See MCP servers, Approval Mode and Sandboxing.