vadgr-computer-use 0.1.1

Local-first MCP server for desktop automation: screenshots, mouse, keyboard

vadgr-computer-use

Local MCP server for desktop automation. 13 tools for capture, mouse, keyboard, and platform introspection. The calling agent takes a screenshot, reasons over the pixels, and drives mouse/keyboard through the server.

Tested with Claude Code, Codex CLI, and Gemini CLI (same server, same tools, same prompt).

Platforms: works on Linux/X11, Windows native, and WSL2 (in that order). macOS support is a work in progress and not usable yet. See Platform support for detail.

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Install

pip install vadgr-computer-use

That ships a console script called vadgr-cua. Verify:

vadgr-cua doctor
# {"daemon_running": false, "windows_python": null, "port": 19542, ...}

On WSL2, the bridge daemon auto-launches the first time a tool is called. On other platforms it's a no-op; direct backends handle everything.

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Wire it into your agent

Pick your client. The server command is vadgr-cua --transport stdio in every case. Each agent launches that stdio process itself, so it needs the full path to the binary unless vadgr-cua is already on the agent's PATH.

First, find the path:

which vadgr-cua
# global install: /home/you/.local/bin/vadgr-cua
# venv install:  /path/to/.venv/bin/vadgr-cua

Substitute that path in each config below.

Claude Code

Project-level (.mcp.json at the repo root you want to automate from):

{
  "mcpServers": {
    "vadgr-computer-use": {
      "type": "stdio",
      "command": "/path/to/vadgr-cua",
      "args": ["--transport", "stdio"]
    }
  }
}

User-level (add to ~/.claude.json under mcpServers with the same shape).

Verify: claude mcp list should print vadgr-computer-use: ... ✓ Connected.

Codex CLI

Add to ~/.codex/config.toml:

[mcp_servers.vadgr-computer-use]
command = "/path/to/vadgr-cua"
args = ["--transport", "stdio"]

Verify: codex mcp list should list vadgr-computer-use with status enabled.

Gemini CLI

gemini mcp add --scope user --trust \
  vadgr-computer-use /path/to/vadgr-cua \
  -- --transport stdio

That writes ~/.gemini/settings.json. Verify by running an interactive session: Gemini shows MCP tool calls inline.

---

Try it

Once the wire-up is done, any of these commands launch the client, which starts vadgr-cua --transport stdio in the background via MCP, and drives your desktop. Same prompt, same tools: pick the client you already use.

Sanity check (focus + Ctrl+A):

Take a screenshot, tell me in one sentence what application is in focus,
then press Ctrl+A and take another screenshot to confirm the action.

Claude Code

Interactive (most common):

claude --dangerously-skip-permissions
# then paste the prompt at the > cursor

Headless one-shot:

claude --dangerously-skip-permissions -p \
  "Take a screenshot, tell me what app is in focus, then press Ctrl+A and screenshot again."

Codex CLI

Headless one-shot (the usual way to drive Codex):

codex exec --dangerously-bypass-approvals-and-sandbox --skip-git-repo-check \
  "Take a screenshot, tell me what app is in focus, then press Ctrl+A and screenshot again."

Expected output (abbreviated):

mcp: vadgr-computer-use/screenshot (completed)
mcp: vadgr-computer-use/key_press (completed)
mcp: vadgr-computer-use/screenshot (completed)
The focused app is <...>; Ctrl+A selected its content.

Gemini CLI

Works end-to-end, but pixel grounding on full-screen shots is weaker than Claude/Codex: first-attempt clicks on small targets can miss by 20-60 px (the model usually recovers via screenshot_region crops). Pass the model explicitly, since the default may silently fall back to an older Gemini on some accounts:

gemini -m gemini-3.1-pro-preview -p \
  "Use only vadgr-computer-use tools. Take a screenshot, tell me what app is in focus, then press Ctrl+A and screenshot again." \
  -y --allowed-mcp-server-names vadgr-computer-use

---

Fuller example: play a song on YouTube Music (Codex)

A Chrome window is already open with a "YouTube Music" tab. One call:

codex exec --dangerously-bypass-approvals-and-sandbox --skip-git-repo-check \
  "Use only vadgr-computer-use MCP tools. In the already-open Chrome,
   switch to the YouTube Music tab, search 'Space Oddity David Bowie',
   and play the first result."

Real transcript (trimmed):

mcp: vadgr-computer-use/screenshot (completed)
mcp: vadgr-computer-use/click (completed)        # YouTube Music tab
mcp: vadgr-computer-use/click (completed)        # search box
mcp: vadgr-computer-use/type_text (completed)
mcp: vadgr-computer-use/key_press (completed)    # enter
mcp: vadgr-computer-use/click (completed)        # first result
mcp: vadgr-computer-use/click (completed)        # dismiss ad overlay
mcp: vadgr-computer-use/screenshot (completed)   # verify now-playing bar
Yes, "Space Oddity" by David Bowie is now playing.

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How it works

The LLM owns the "where to click" decision; the server owns "how to click it precisely". No other abstraction in between.

Platform support

Platform	Screenshots	Mouse / keyboard	Status
Linux / X11	mss	xdotool	primary target
Windows native	Win32 GDI	SendInput	should work; not in the v0.1.0 CI matrix
WSL2 → Windows host	TCP bridge daemon (mss on Windows)	TCP bridge daemon (Win32 SendInput)	well-tested
macOS	screencapture	osascript / cliclick	WIP, not functional yet

If the WSL2 daemon can't start (e.g. no Windows Python available), the server falls back to a slower PowerShell path. See Daemon management below.

MCP tools (13)

Capture (2)

• screenshot(): full screen, downscaled to CU_MAX_WIDTH (auto-picks 1024 / 1280 / 1366).
• screenshot_region(x, y, w, h): cropped region.

Input (8)

• click(x, y) / double_click(x, y) / right_click(x, y)
• move_mouse(x, y) / drag(start_x, start_y, end_x, end_y, duration=0.5)
• scroll(x, y, amount): positive = up, negative = down
• type_text(text) / key_press(keys): keys like ctrl+s, alt+tab, enter

Platform info (3)

• get_platform() / get_platform_info() / get_screen_size()

Daemon management (WSL2)

Most users never touch this. For when you do:

vadgr-cua doctor           # JSON: platform, Windows Python, daemon state, port, hash
vadgr-cua install-daemon   # Eager deploy + launch
vadgr-cua stop-daemon      # Kill the running daemon
vadgr-cua restart-daemon   # Stop then start

The daemon file is deployed to %USERPROFILE%\vadgr\daemon.py and listens on TCP 127.0.0.1:19542. After pip install -U vadgr-computer-use, the next MCP session detects the version-hash drift via a ping handshake and redeploys the daemon automatically.

Library usage

from computer_use import ComputerUseEngine

engine = ComputerUseEngine()
shot = engine.screenshot()
engine.click(500, 300)
engine.type_text("hello")

The library is just the input/capture primitives, no LLM or agent loop inside. To drive it with a model, point an MCP client (Claude Code, Codex, Gemini, or your own) at the vadgr-cua server as shown above.

Environment

Variable	Purpose
CU_MAX_WIDTH	Override screenshot downscale target (default: auto 1024/1280/1366)
CUE_BRIDGE_PORT	Override WSL2 bridge daemon TCP port (default: 19542)
VADGR_DEBUG	Set to 1 to dump screenshots to <package>/.debug/

Tests

pip install -e ".[dev]"
pytest computer_use/tests -q

License

Apache 2.0. See LICENSE.

Part of Vadgr

• vadgr: workflow engine (brain)
• vadgr-computer-use: desktop automation MCP (eyes)
• vadgr-agent-os: containerized agent runtime