Review website image delivery and configure an image CDN, a service that optimizes and distributes images. Check file formats, dimensions, loading behavior, and initial screen impact, with guidance on verifying changes in DevTools.
Use when reviewing image assets, markup, and CDN or build transforms related to Serve images from a CDN. Check encoded size, rendered size, loading strategy, and above-the-fold impact together.
Check whether website images are delivered through a CDN or another image optimization service, and get help reviewing the configuration. A CDN delivers images from distribution locations; image services can also resize them automatically and convert them to WebP or AVIF. The review examines image files, HTML, and delivery settings to identify specific files or components with problems in format, dimensions, or loading behavior.
Use it when you want to optimize images during delivery or serve images sized for the screen. It checks file size alongside actual display dimensions and the effect on the part of the page visible when it first opens. It also explains image size generation through URL parameters and the role of caching at nearby distribution locations.
Introducing image CDN optimization requires configuring the service you choose.
This overview was written by AI (OpenAI Codex) from the public SKILL.md. Check the original below for the exact behavior.
AI rated this skill on four points using only the contents of its SKILL.md. Stars and popularity are not taken into account.
The total counts each point as A = 25, B = 15, C = 5. Rated by AI (OpenAI Codex) as of Oct 23, 2026. Treat it as a guide and read the original before installing.
Review the instructions the agent will receive before you install.
Image CDNs automatically optimize, resize, and convert images on-the-fly—delivering the smallest file in the best format without manual processing.
Verify if images are served from a CDN or image optimization service.
Configure an image CDN like Cloudinary, Imgix, or Cloudflare Images for automatic optimization.
Explain how image CDNs provide on-the-fly optimization, resizing, and format conversion.
Review image assets, markup, and delivery configuration related to Serve images from a CDN. Flag exact files or components where format choice, sizing, or loading behavior violates the rule, and describe how to confirm the fix in DevTools.
For full implementation details, code examples, and framework-specific guidance,
see references/rule.md.
Rule page: https://frontendchecklist.io/rules/images/image-cdn
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