performance-audit

Performance Audit Skill

Analyze web page performance using Web Vitals and network timing metrics.

When to Use

This skill activates when:

• User asks about page performance or speed
• User wants to optimize load times
• User mentions slow page or poor user experience
• User needs Core Web Vitals metrics
• User asks about SEO performance factors

Capabilities

Web Vitals Analysis

• Get Core Web Vitals (o11y_get-web-vitals)
  • LCP (Largest Contentful Paint)
  • INP (Interaction to Next Paint)
  • CLS (Cumulative Layout Shift)
  • TTFB (Time to First Byte)
  • FCP (First Contentful Paint)

Network Performance

• Analyze request timing (o11y_get-http-requests)
• Identify slow API calls
• Check resource sizes
• Find blocking resources

Visual Analysis

• Capture page at different load stages
• Identify layout shifts visually
• Check above-the-fold content

JavaScript Analysis

• Profile JavaScript execution
• Check for long tasks
• Identify render-blocking scripts

Performance Thresholds

Metric	Good	Needs Work	Poor
LCP	≤2.5s	2.5-4s	>4s
INP	≤200ms	200-500ms	>500ms
CLS	≤0.1	0.1-0.25	>0.25
TTFB	≤800ms	800-1800ms	>1800ms

Audit Workflow

1. Baseline: Get initial Web Vitals metrics
2. Network: Analyze slow/large requests
3. Resources: Check for render-blocking resources
4. JavaScript: Look for long tasks
5. Images: Check for unoptimized images
6. Report: Summarize with recommendations

Common Issues

• Large unoptimized images
• Render-blocking CSS/JS
• Too many HTTP requests
• Slow server response (TTFB)
• Layout shifts from dynamic content
• Uncompressed resources