Screenshot Stitcher

Use this skill when the user wants to combine multiple iPhone screenshots into one long image.

The CLI contract is intentionally small, so the same workflow ports cleanly into Claude, Codex, OpenClaw, Hermes, and similar agent wrappers that can invoke shell commands. The tool is OpenCV/NumPy-driven local image processing, not AI image generation.

Privacy

All image processing happens locally in the user's Python process. The CLI reads screenshots from disk, writes the stitched output back to disk, and does not upload screenshots, filenames, or image metadata to any external service.

Install The CLI

Prefer the published PyPI package:

pip install screenshot-stitcher
screenshot-stitcher --help

If the machine has multiple Python environments, install into the environment the agent will use:

python -m pip install screenshot-stitcher
screenshot-stitcher --help

If the package is already installed, skip installation and use the CLI directly.

Workflow

1. Confirm the inputs are vertically scrolling screenshots from the same device width.
2. Preserve the user's input order. Do not reorder by timestamp.
3. Use the installed CLI:

screenshot-stitcher img1.png img2.png img3.png -o output.png

1. If the package cannot be installed but the agent is inside a cloned checkout, run the repo entrypoint instead:

python3 main.py img1.png img2.png img3.png -o output.png

1. After writing the output file, report the path and mention any low-confidence overlaps printed by the CLI.

Useful Flags

• --no-navbar: page has no navigation bar
• --no-tabbar: page has no bottom tab bar
• --top-crop N: manual top crop override
• --bottom-crop N: manual bottom crop override
• --x-margin N: ignore more left/right edge pixels during matching
• --template-height N: adjust the template height used for overlap matching
• --threshold V: raise or lower overlap acceptance sensitivity

Heuristics

• Start with the default command before tuning flags.
• If the page has sticky bars, floating controls, or scroll indicators, try a larger --x-margin.
• If the top chrome changes during scrolling, try --no-navbar or a custom --top-crop.
• If overlap confidence is low but the output is visually correct, report that explicitly instead of pretending the score is strong.
• If the input screenshots are out of order or have different widths, stop and surface that clearly.