Analyze performance with WebPageTest
SkillWeb & browsingWebpagetest is a skill for AI agents that tests web page speed using WebPageTest. It is meant for reviewing templates, rendered HTML, or shared components, so the agent validates the final browser-facing markup rather than just the source framework abstraction.
Available today. Use it from your connected AI after setup.
No other account needed.
Have an AI agent that can load skills.
Then ask your AI: use the Analyze performance with WebPageTest skill
What your AI can do with it
- Test web page speed using WebPageTest
- Review templates for performance issues
- Analyze rendered HTML, not just source framework abstraction
- Check shared components related to performance
- Validate final browser-facing markup
Getting started
- Have an AI agent that can load skills.
- Add the webpagetest skill to the agent's available skills.
- Ask the agent to review a template, rendered HTML, or shared component, and it will use the skill to analyze performance with WebPageTest.
What this skill tells your AI
The instructions your AI receives, as published by thedaviddias/front-end-checklist in skills/webpagetest/SKILL.md and read by ahel’s review.
WebPageTest reveals real-world performance issues that synthetic tools miss—like TTFB from actual locations, render-blocking patterns, and third-party script impact.
Quick Reference
- Run 3+ tests to get consistent results
- Test from locations near your users
- Use filmstrip view to identify visual progress
- Check waterfall for blocking resources and slow third-parties
Check
Use WebPageTest to analyze page performance, identify bottlenecks, and measure real-world loading metrics across different devices and connections.
Fix
Implement recommended optimizations from WebPageTest results including resource compression, caching, and critical path improvements.
Explain
Explain how WebPageTest provides insights into Core Web Vitals, loading waterfalls, and performance opportunities that synthetic testing can't reveal.
Code Review
Review templates, server-rendered HTML, and shared components that output markup related to Analyze performance with WebPageTest. Flag exact elements, attributes, and routes where the rendered HTML violates the rule.
For full implementation details, code examples, and framework-specific guidance,
see references/rule.md.
Rule page: https://frontendchecklist.io/en/rules/html/webpagetest
Signals
- GitHub stars
- 74k
- Forks
- 7k
- Last commit
- Aug 2026
ahel review
K1binfo
installs-packages (in references/rule.md)
Automated review, not a security audit. Ruleset v1+k2.
Questions
- When should this skill be used?
- Use it when reviewing templates, rendered HTML, or shared components related to analyzing performance with WebPageTest.
- Does it check the source code or the rendered page?
- It validates the final browser-facing markup, not just the source framework abstraction.
- What does the skill do?
- It lets your agent test web page speed using WebPageTest when checking rendered HTML and site templates.
Advanced
- Item type
- skill
- Key
webpagetest- Source
- github.com/thedaviddias/front-end-checklist