winctl

<p align="center">
  <img src="assets/icon-256.png" width="128" height="128" alt="WinCtl">
</p>

<h1 align="center">WinCtl</h1>

<p align="center">
  <b>Full Windows desktop access for Claude and other MCP clients</b><br>
  See the screen, read and drive real application UIs, manage windows and
  processes, work with files, and run shell commands — all behind a tiered
  permission model with audit logging.
</p>

[![npm](https://img.shields.io/npm/v/@sitharaj88/winctl)](https://www.npmjs.com/package/@sitharaj88/winctl)
[![license](https://img.shields.io/badge/license-MIT-blue)](LICENSE)

---

## Why this connector

Most desktop automation servers hand the model a screenshot and a `click(x, y)`
tool, which breaks the moment a window moves. This one is built around the
things that actually make Windows automation reliable:

- **UI Automation first.** `uia_snapshot` reads an application's accessibility
  tree, so Claude can act on *"the Save button"* rather than on coordinates that
  go stale. `uia_invoke` and `uia_set_value` drive controls directly.
- **Correct coordinates, always.** The process declares per-monitor DPI
  awareness before touching any UI API, and reports the DWM frame bounds rather
  than the raw window rect (which includes an invisible ~7px resize border).
  Without this, every coordinate on a scaled display is silently wrong — on a
  200% display, `GetWindowRect` reports 1351px where the true edge is 2641px.
- **Input that actually arrives.** Synthetic typing is paced, because batching
  Unicode key events makes applications drop and repeat characters. Text over
  200 characters is pasted via the clipboard instead, and your clipboard is
  restored afterwards.
- **Handles that cannot betray you.** Window ids are opaque and fingerprinted;
  Windows recycles window handles, and a stale one silently retargeting to a
  different app is exactly how automation closes the wrong window.
- **Honest failures.** `window_focus` verifies the foreground actually changed
  and says so when Windows refuses. Errors explain what to do next rather than
  surfacing an HRESULT.

## Requirements

- Windows 10 (1809+) or Windows 11
- Node.js 20 or newer
- No compiler or build tools — every native dependency ships prebuilt binaries

## Install

### Claude Desktop (recommended)

Download `winctl.mcpb` from the
[latest release](https://github.com/sitharaj88/winctl/releases) and
double-click it. Claude Desktop installs it and exposes the permission profile,
allowed folders and confirmation settings in its UI.

### Claude Code

Install globally first, then register the command:

```bash
npm install -g @sitharaj88/winctl
claude mcp add winctl -- winctl
```

Add `--scope user` to the second command to make it available in every project
rather than just the current one.

> **Don't use `npx -y @sitharaj88/winctl` here.** It works, but WinCtl depends on
> prebuilt native binaries (sharp, koffi), and npx re-resolves them on every
> launch — around 18 seconds versus 3 for a global install. MCP clients give up
> long before that and report `Connection closed`.

### Any MCP client (manual)

```jsonc
{
  "mcpServers": {
    "winctl": {
      "command": "winctl",
      "env": {
        "WINCTL_PROFILE": "standard"
      }
    }
  }
}
```

If `winctl` isn't on your `PATH`, point at the entry point directly — on Windows
a global npm install lands in `%APPDATA%\npm\node_modules`:

```jsonc
{
  "mcpServers": {
    "winctl": {
      "command": "node",
      "args": ["C:\\Users\\<you>\\AppData\\Roaming\\npm\\node_modules\\@sitharaj88\\winctl\\dist\\index.js"]
    }
  }
}
```

Claude Desktop's config lives at
`%APPDATA%\Claude\claude_desktop_config.json`.

## Permission tiers

Every tool belongs to exactly one tier. **Tools in a disabled tier are never
registered**, so the model cannot see them, attempt them, or spend context
reading their descriptions.

| Tier | What it allows |
|---|---|
| `observe` | Screenshots, window/monitor enumeration, UI trees, system and process info, file reads |
| `interact` | Mouse and keyboard input, UI Automation invokes, window focus/move/close, clipboard writes |
| `filesystem` | Creating, modifying, moving and deleting files |
| `manage` | Starting and terminating processes, controlling services |
| `shell` | Arbitrary PowerShell and cmd execution |

Profiles bundle these:

| Profile | Tiers |
|---|---|
| `readonly` | `observe` |
| `standard` *(default)* | `observe`, `interact`, `filesystem` |
| `full` | all five |

```bash
# Pick a profile
WINCTL_PROFILE=readonly

# …or choose tiers explicitly
WINCTL_TIERS=observe,interact
```

### Configuration

| Variable | Default | Purpose |
|---|---|---|
| `WINCTL_PROFILE` | `standard` | `readonly`, `standard` or `full` |
| `WINCTL_TIERS` | — | Explicit tier list, overrides the profile |
| `WINCTL_ALLOWED_PATHS` | — | Semicolon-separated folders file tools may touch |
| `WINCTL_DENIED_PATHS` | — | Extra folders to refuse |
| `WINCTL_CONFIRM_DESTRUCTIVE` | `true` | Ask before destructive actions |
| `WINCTL_AUDIT_LOG` | `%LOCALAPPDATA%\winctl\audit.jsonl` | Audit log path |
| `WINCTL_AUDIT_DISABLED` | `false` | Turn auditing off |
| `WINCTL_MAX_IMAGE_WIDTH` | `1600` | Screenshot downscale width |
| `WINCTL_COMMAND_TIMEOUT_MS` | `60000` | Shell/PowerShell time limit |

An unrecognised profile name fails closed to `readonly` with a warning on
stderr, rather than guessing what you meant and possibly granting write access.

## Tools

<details>
<summary><b>Screen</b> (5)</summary>

| Tool | Tier | Description |
|---|---|---|
| `screen_list_monitors` | observe | Displays with position, resolution and DPI scale |
| `screen_capture` | observe | Screenshot a monitor or the whole virtual desktop |
| `screen_capture_region` | observe | Screenshot a rectangular region |
| `screen_capture_window` | observe | Screenshot one window, even if overlapped |
| `screen_list_capturable_windows` | observe | Windows available for individual capture |

</details>

<details>
<summary><b>Windows</b> (7)</summary>

| Tool | Tier | Description |
|---|---|---|
| `window_list` | observe | Visible top-level windows with stable ids and bounds |
| `window_get_active` | observe | The window with keyboard focus |
| `window_get_desktop_info` | observe | Virtual desktop bounds and cursor position |
| `window_focus` | interact | Raise and focus a window, with verification |
| `window_set_state` | interact | Minimize, maximize, restore, hide, show |
| `window_move` | interact | Move and resize (un-maximizes first) |
| `window_close` | interact | Ask a window to close |

</details>

<details>
<summary><b>Input</b> (7)</summary>

| Tool | Tier | Description |
|---|---|---|
| `input_move_mouse` | interact | Move the cursor |
| `input_click` | interact | Click, right-click or double-click |
| `input_drag` | interact | Drag between two points, interpolated |
| `input_scroll` | interact | Scroll vertically or horizontally |
| `input_type` | interact | Type Unicode text, or paste when long |
| `input_press_keys` | interact | Chords such as `ctrl+shift+escape` |
| `input_key_hold` | interact | Hold or release a key |

</details>

<details>
<summary><b>UI Automation</b> (4)</summary>

| Tool | Tier | Description |
|---|---|---|
| `uia_snapshot` | observe | Read an application's accessibility tree |
| `uia_find` | observe | Find controls by name, id or type |
| `uia_invoke` | interact | Click, toggle, expand, select or focus a control |
| `uia_set_value` | interact | Set an editable control's text directly |

</details>

<details>
<summary><b>System &amp; processes</b> (8)</summary>

| Tool | Tier | Description |
|---|---|---|
| `system_info` | observe | OS, CPU, memory, disks, network, battery, GPU |
| `system_list_services` | observe | Services with state and startup type |
| `system_list_installed_apps` | observe | Installed applications |
| `system_notify` | interact | Windows toast notification |
| `system_control_service` | manage | Start, stop or restart a service |
| `process_list` | observe | Processes with CPU and memory usage |
| `process_start` | manage | Launch an application or open a document |
| `process_kill` | manage | Terminate a process |

</details>

<details>
<summary><b>Files, clipboard &amp; shell</b> (9)</summary>

| Tool | Tier | Description |
|---|---|---|
| `file_known_folders` | observe | Standard Windows paths and current access limits |
| `file_list` | observe | Directory listing with sizes and timestamps |
| `file_read` | observe | Read text or base64 content |
| `file_search` | observe | Find files by name pattern and content |
| `file_write` | filesystem | Write, append or create |
| `file_manage` | filesystem | Copy, move, delete, mkdir |
| `clipboard_read` | observe | Read clipboard text |
| `clipboard_write` | interact | Set clipboard text |
| `shell_run` | shell | Run a PowerShell or cmd command |

</details>

**40 tools total.** Every one carries `title`, `readOnlyHint` and
`destructiveHint` annotations.

## Example

> *"Open Notepad, write my meeting notes into it and save to Documents."*

Claude will typically:

1. `process_start` → launch Notepad
2. `window_list` → find the window and its **owning** process id
3. `window_focus` → make sure keystrokes land there
4. `input_type` → paste the notes via the clipboard
5. `input_press_keys` `ctrl+s`, then `uia_set_value` on the filename field
6. `screen_capture_window` → confirm the result visually

## Safety

- **Tier gating** is the primary boundary — disabled tools are never exposed.
- **Path containment** resolves symlinks before checking, so a link inside an
  allowed folder cannot reach a denied one. `System32`, `WinSxS`, `Boot` and the
  Startup folder are refused in *every* profile, including `full`.
- **Confirmation** via MCP elicitation before destructive actions.
- **Audit log** of every call in JSONL, with sensitive-looking arguments
  redacted. See [PRIVACY.md](PRIVACY.md).
- **Modifier release** on shutdown, so a cras