Convert To Webp

Convert to WebP

Convert one or more images to WebP format.

Usage

Arguments: one or more file paths, optionally followed by --dest <directory> and/or --quality <number>.

Examples:

• /convert-to-webp /tmp/screenshot.png
• /convert-to-webp /tmp/a.png /tmp/b.jpg --dest /path/to/site/static/images
• /convert-to-webp /tmp/photo.jpg --quality 90

Instructions

First, check which tool is available (run once per session):

1. cwebp -- best quality control. Install via brew install webp
2. sips -- built into macOS (Monterey+), no install needed. No quality flag for WebP output.

Pick whichever is available. Prefer cwebp if both exist.

For each input file:

1. Skip if the file is already .webp
2. Determine the output path:
   • If --dest is provided, output to that directory with the same filename but .webp extension
   • Otherwise, output to the same directory as the input with .webp extension
3. Convert:
   • cwebp: cwebp -q <quality> <input> -o <output> (default quality: 85)
   • sips: sips -s format webp <input> --out <output>
4. Report the output path and file size

Provenance

This skill drives two interchangeable command-line tools and bundles neither:

• cwebp — part of Google's libwebp (© Google, BSD-3-Clause), installed separately via brew install webp.
• sips — Apple's Scriptable Image Processing System, built into macOS.

The skill documents the conversion workflow; it is not affiliated with or endorsed by Google or Apple. The MIT license covers this skill's content, not the wrapped tools.