@cynosure-mcp/computer-controller

MCP server for desktop automation — launch apps, capture screenshots, control mouse and keyboard. Supports multi-monitor setups and Gemini-optimized screenshot scaling.

Installation

npx @cynosure-mcp/computer-controller

Or install globally:

npm install -g @cynosure-mcp/computer-controller
computer-controller

Tools

| Tool | Description | | ----------------------- | --------------------------------------------- | | list_applications | Index and search installed applications | | launch_application | Launch an application by name | | get_screenshot | Capture the desktop (multi-monitor support) | | get_cursor_area | 512×512 screenshot centered on the cursor | | move_mouse | Move cursor to a position | | click_mouse | Click at current or specified position | | double_click | Double-click at current or specified position | | drag_mouse | Click-and-drag between positions | | scroll_mouse | Scroll the mouse wheel | | get_mouse_position | Get current cursor location | | type_text | Insert text at cursor | | press_key_combination | Press key combo (e.g., ctrl+c) | | get_screen_size | Get display dimensions | | get_system_details | OS, CPU, memory, and disk info | | wait | Pause for 1–10 seconds |

Configuration

| Variable | Required | Description | | --------------- | -------- | ------------------------------------------------------------------------------------------------------ | | DISPLAY_INDEX | No | Restrict to a specific monitor. 0 or unset = all displays; 1 = primary; 2 = second display; etc. | | GEMINI_MODE | No | Set to true to scale screenshots to fit within 1000×1000 for Gemini models |

Screenshot Scaling

Screenshots are automatically scaled to fit within model-friendly dimensions. In standard mode (optimized for Claude Sonnet) the output is downscaled to one of 1024×768, 1280×800, or 1280×720 depending on screen aspect ratio.

When GEMINI_MODE is enabled, all screenshots are scaled to fit within a 1000×1000 bounding box (maintaining aspect ratio) and bottom-padded with black to exactly 1000×1000. Content always starts at coordinate (0, 0).

| Resolution | Scale Factor | Content Area | Bottom Padding | | ---------- | ------------ | ------------ | -------------- | | 1920×1080 | 0.5208 | 1000×563 | 437px | | 2560×1440 | 0.3906 | 1000×563 | 437px | | 3840×2160 | 0.2604 | 1000×563 | 437px | | 1920×1200 | 0.5208 | 1000×625 | 375px |

MCP Config

{
  "mcpServers": {
    "computer-controller": {
      "command": "npx",
      "args": ["@cynosure-mcp/computer-controller"],
      "env": {
        "GEMINI_MODE": "true"
      }
    }
  }
}

License

MIT