nucliweb/webperf
.claude/skills/webperf/SKILL.md
Web performance measurement and debugging toolkit. Use when the user asks about web performance, wants to audit a page, or says "analyze performance", "debug lcp", "check ttfb", "measure core web vitals", "audit images", or similar.
$ install --global
skillsauthnpx skillsauth add nucliweb/webperf-snippets webperfInstall this skill globally with one command. Works with Claude Code, Cursor, and Windsurf.
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Last scanned: Apr 7, 2026, 8:24 PM26.5s1 file scanned
SKILL.md
- name:
- webperf
- description:
- Web performance measurement and debugging toolkit. Use when the user asks about web performance, wants to audit a page, or says "analyze performance", "debug lcp", "check ttfb", "measure core web vitals", "audit images", or similar.
- context:
- fork
- license:
- MIT
- author:
- Joan Leon | @nucliweb
- version:
- 1.1.0
- mcp-server:
- chrome-devtools
- category:
- web-performance
- repository:
- https://github.com/nucliweb/webperf-snippets
WebPerf Snippets Toolkit
A collection of 47 JavaScript snippets for measuring and debugging web performance in Chrome DevTools. Each snippet runs in the browser console and outputs structured, color-coded results.
Quick Reference
| Skill | Snippets | Trigger phrases | |-------|----------|-----------------| | webperf-core-web-vitals | 7 | "debug LCP", "slow LCP", "CLS", "layout shifts", "INP", "interaction latency", "responsiveness" | | webperf-loading | 28 | "TTFB", "slow server", "FCP", "render blocking", "font loading", "script loading", "resource hints", "service worker" | | webperf-interaction | 8 | "jank", "scroll performance", "long tasks", "animation frames", "INP debug" | | webperf-media | 3 | "image audit", "lazy loading", "image optimization", "video audit" | | webperf-resources | 1 | "network quality", "bandwidth", "connection type", "save-data" |
Workflow
- Identify the relevant skill based on the user's question (see Quick Reference above)
- Load the skill's skill.md to see available snippets and thresholds
- Execute with Chrome DevTools MCP:
mcp__chrome-devtools__navigate_page→ navigate to target URLmcp__chrome-devtools__evaluate_script→ run the snippetmcp__chrome-devtools__get_console_message→ read results
- Interpret results using the thresholds defined in the skill
- Provide actionable recommendations based on findings
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