Use when reviewing image assets, markup, and CDN or build transforms related to Fix broken images. Check encoded size, rendered size, loading strategy, and above-the-fold impact together.
インストールする前に、エージェントに与えられる指示の中身を確認できます。
A broken image shows an ugly placeholder icon, breaks visual layouts, and communicates that the site is poorly maintained. If the broken image is the Largest Contentful Paint element, it also harms LCP scores. On e-commerce sites, a missing product image can directly reduce purchase intent.
<img src> paths at build timeonerror handlers to swap broken <img> elements to fallback imagesthis.onerror=null inside the handler to prevent infinite error loopsScan all <img> src attributes and CSS background-image URLs in this codebase. Identify: 1) Any relative or absolute paths that point to files not present in the project. 2) Any <img> elements without an onerror handler or fallback mechanism. 3) Hardcoded external image URLs that may become unavailable. 4) Dynamic image paths constructed from user data without existence checks. Report each broken or potentially broken image with its file path and line number.
For each broken image: 1) Correct the file path if the image exists but the path is wrong. 2) Add the missing image asset if it was omitted. 3) For images that may fail at runtime, add an onerror handler: onerror="this.src='/images/fallback.png'; this.onerror=null;". 4) For React/Vue components, implement an onError callback that swaps the src to a placeholder. 5) For external images, consider downloading and self-hosting or using a CDN with fallback. Always set this.onerror=null to prevent infinite error loops.
Explain why broken images degrade user experience and how browsers handle them. A 404 response for an image shows the browser's broken-image icon, causes a console error, and—if the image is the LCP element—delays Core Web Vitals metrics. Search engines cannot index missing images, affecting image SEO. Monitoring image errors proactively prevents broken experiences from reaching users.
Review image assets, markup, and delivery configuration related to Fix broken images. 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/broken-images
まだレビューはありません。使ってみた感想をお寄せください。
概要と使いどころ
Use when reviewing templates, rendered HTML, or shared components related to Create a custom 404 error page. Validate the final browser-facing markup, not just the source framework abstraction.
日本語の概要は準備中です。原文の説明を表示しています。
Use when auditing metadata, crawlability, structured data, or indexability related to Create a dedicated About page. Verify the rendered HTML and HTTP response rather than relying only on source files.
日本語の概要は準備中です。原文の説明を表示しています。
Use when reviewing component libraries, page flows, or CI pipelines that need repeatable accessibility checks. Automated testing is strongest at catching structural and attribute-level issues; it does not replace keyboard, screen reader, and manual UX testing.
日本語の概要は準備中です。原文の説明を表示しています。
Use when reviewing sign-in, sign-up, MFA, CAPTCHA, recovery, and re-auth flows. Evaluate the full authentication path, including error handling and backup methods, not just the primary login form.
日本語の概要は準備中です。原文の説明を表示しています。
Use when reviewing templates, rendered HTML, or shared components related to Make notifications accessible. Validate the final browser-facing markup, not just the source framework abstraction.
日本語の概要は準備中です。原文の説明を表示しています。
Use when reviewing rendered HTML, interactive components, or design-system patterns related to Use semantic table markup for screen readers. Check native semantics first, then inspect keyboard behavior, focus flow, accessible names, and screen-reader output where relevant.
日本語の概要は準備中です。原文の説明を表示しています。