Is this skill suitable for SEO optimization?

Absolutely. Page speed and Core Web Vitals are critical ranking factors for search engines, and this tool helps you identify the technical HTML issues that might be hurting your SEO.

Can I get the performance audit results in a machine-readable format?

Yes, the skill supports a --json flag which outputs the results as JSON for easy integration into automated CI/CD pipelines or custom reporting tools.

What specific performance issues does this skill detect?

It identifies render-blocking CSS/JS, missing lazy loading, large inline styles or scripts over 14KB, and missing image dimensions that cause layout shifts.

Does this tool provide code fixes for the issues it finds?

Yes, it includes a 'Quick Fixes' section in its output with specific HTML snippets for preconnecting domains, deferring scripts, and lazy-loading images.

How does it help with Core Web Vitals?

It specifically targets LCP (Largest Contentful Paint) by identifying critical resources to preload and CLS (Cumulative Layout Shift) by ensuring images have defined dimensions.

HTML Performance Checker

Name: HTML Performance Checker
Author: leobrival

byleobrival

分析与监控

Analyzes HTML documents to identify performance bottlenecks, render-blocking resources, and Core Web Vitals optimizations.

关于

The HTML Performance Checker skill empowers Claude to audit web pages for critical performance issues directly from the command line. It scans for high-impact problems like render-blocking CSS and JavaScript, missing lazy loading attributes, and absent resource hints such as preconnect or preload. By evaluating patterns that negatively affect Largest Contentful Paint (LCP) and Cumulative Layout Shift (CLS), it provides developers with a performance score, a detailed breakdown of resource loading, and actionable code snippets to improve site speed and user experience.

主要功能

Audits resource hints including preconnect, preload, and dns-prefetch for third-party domains.
Provides a comprehensive performance score and specific remediation recommendations.
Flags layout shift (CLS) risks caused by images missing width and height dimensions.
Identifies images and iframes missing the loading='lazy' attribute.
Detects render-blocking CSS and JavaScript files in the document head.
0 GitHub stars

使用场景

Automating performance health checks during the development of new web components.
Auditing a landing page's Core Web Vitals compliance before a production launch.
Identifying third-party scripts that are slowing down initial page rendering.

关于

主要功能

Audits resource hints including preconnect, preload, and dns-prefetch for third-party domains.
Provides a comprehensive performance score and specific remediation recommendations.
Flags layout shift (CLS) risks caused by images missing width and height dimensions.
Identifies images and iframes missing the loading='lazy' attribute.
Detects render-blocking CSS and JavaScript files in the document head.
0 GitHub stars

使用场景

Automating performance health checks during the development of new web components.
Auditing a landing page's Core Web Vitals compliance before a production launch.
Identifying third-party scripts that are slowing down initial page rendering.