Claude Vision MCP

A Model Context Protocol server that gives Claude Code the ability to see — capturing the screen, individual windows, screen regions, and live web pages, plus comparing screenshots for visual-regression checks.

Built so an AI coding agent can verify its own visual output: render a UI change, screenshot it, and look at the result instead of guessing.

Features

Six tools, exposed over MCP via FastMCP:

• capture_screen — screenshot the full screen or a specific display, with token-aware downscaling.
• capture_window_tool — screenshot a single window by (partial, case-insensitive) title or app name.
• capture_screen_region — screenshot an arbitrary rectangular region by coordinates.
• capture_webpage_tool — screenshot any URL (including localhost dev servers) via a headless Playwright browser; supports full-page capture and waiting on a CSS selector.
• compare_screenshots — diff two images and report the percentage and region of changed pixels (visual regression).
• list_windows — list all open windows as Application | Window Title to find a capture target.

Requirements

• Python ≥ 3.10
• macOS (window capture uses AppleScript; screen capture needs Screen Recording permission)
• Dependencies: mcp[cli], Pillow, playwright, numpy

Install

git clone https://github.com/wonderstone843/claude-vision-mcp.git
cd claude-vision-mcp
pip install -e .
playwright install chromium   # only needed for capture_webpage_tool

Grant Screen Recording permission to your terminal in System Settings → Privacy & Security → Screen Recording.

Use with Claude Code

Register the server (stdio):

claude mcp add claude-vision -- claude-vision-mcp

Or add it to your MCP config manually:

{
  "mcpServers": {
    "claude-vision": {
      "command": "claude-vision-mcp"
    }
  }
}

Then ask Claude to, e.g., "screenshot localhost:3000 and check the hero section renders," or "capture the Blender window."

Project layout

claude_vision_mcp/
  server.py     # FastMCP server + the 6 tool definitions
  capture.py    # full-screen / window / region capture
  windows.py    # AppleScript window enumeration
  browser.py    # Playwright headless webpage capture
  compare.py    # pixel-diff comparison

License

MIT — see LICENSE.

Author: Joshua Penn