mcpField
S
screenshot

screenshot

github.com/ninehillsProductivity27738 installsUpdated 18w ago
Repository

About screenshot

Screenshot is a macOS screenshot Skill that captures the screen, a window, or a selected region through Bash and screencapture. It emphasizes resizing images before reading them to keep their context footprint manageable.

Key features

  1. 01Capture the full screen
  2. 02Select a window interactively
  3. 03Capture a specified region
  4. 04Resize images and adjust compression
  5. 05Read image dimensions

Use cases

  1. 01Capture the screen for visual inspection
  2. 02Take a screenshot of a window or UI region
  3. 03Resize an image before model review

Install

Copy the command and run it in a terminal.

$npx skills add https://github.com/ninehills/skills --skill screenshot

After installing, type/screenshotin Claude Code to confirm it loaded.

Bundled files

References and scripts installed along with SKILL.md.

LICENSE.txt
agents/
openai.yaml
scripts/
ensure_macos_permissions.sh
macos_display_info.swift
macos_permissions.swift
macos_window_info.swift
take_screenshot.ps1
take_screenshot.py

Details

From the project README

Screenshot Skill

Take screenshots using macOS screencapture command via Bash.

Important: Always Resize for Context

Full-resolution screenshots (especially on Retina/5K displays) produce huge base64 that will exceed the model's context length. Always resize before reading.

Take and View a Screenshot

# 1. Capture full screen
/usr/sbin/screencapture -x -t jpg /tmp/alma-screenshot.jpg

# 2. Resize to 1024px wide (critical for context size!)
/usr/bin/sips --resampleWidth 1024 --setProperty formatOptions 60 /tmp/alma-screenshot.jpg --out /tmp/alma-screenshot-thumb.jpg 2>/dev/null

# 3. Get dimensions
/usr/bin/sips -g pixelWidth -g pixelHeight /tmp/alma-screenshot.jpg 2>/dev/null

Then use the Read tool to read /tmp/alma-screenshot-thumb.jpg (the resized version, NOT the full-size one).

Capture Options

# Full screen (default)
/usr/sbin/screencapture -x -t jpg /tmp/alma-screenshot.jpg

# Interactive window selection
/usr/sbin/screencapture -x -w -t jpg /tmp/alma-screenshot.jpg

# Specific region (x,y,w,h)
/usr/sbin/screencapture -x -R 0,0,800,600 -t jpg /tmp/alma-screenshot.jpg

# With 3-second delay
/usr/sbin/screencapture -x -T 3 -t jpg /tmp/alma-screenshot.jpg

Send Screenshot to User (Telegram)

If the user wants to see the screenshot directly, use the alma CLI or just describe what you see. The full-resolution file is at /tmp/alma-screenshot.jpg.

Tips

  • Always resize before reading into context — use the thumb version
  • -x flag suppresses the capture sound
  • -t jpg outputs JPEG (smaller than PNG)
  • Use sips --setProperty formatOptions 60 for higher compression if needed

Comments

Markdown supported