Webperf Loading
Intelligent loading performance analysis with automated workflows for TTFB...
Install
npx skills add nucliweb/webperf-snippets --skill webperf-loading -g -a claude-code -y- Repository
- nucliweb/webperf-snippets1.5k
- Category
- AI and agents
- Updated
- 3d ago
- License
- MIT
- Context cost
- Mediumabout 3,000 tokens
- Runs scripts
- Yes, review before use
What it does
Intelligent loading performance analysis with automated workflows for TTFB investigation (DNS/connection/server breakdown), render-blocking detection, script performance deep dive (first vs third-party attribution), font optimization, and resource hints validation. Includes decision trees that automatically analyze TTFB sub-parts when slow, detect script loading anti-patterns (async/defer/preload conflicts), identify render-blocking resources, and validate resource hints usage. Features workflows for complete loading audit (6 phases), backend performance investigation, and priority optimization. Cross-skill integration with Core Web Vitals (LCP resource loading), Interaction (script execution blocking), and Media (lazy loading strategy). Use when the user asks about TTFB, FCP, render-blocking, slow loading, font performance, script optimization, or resource hints. Compatible with Chrome DevTools MCP.
WebPerf: Loading Performance
JavaScript snippets for measuring web performance in Chrome DevTools.
Running a script
- Run the script with
mcp__chrome-devtools__evaluate_scriptand read the object it returns. The scripts have no console output, so the returned object is the result:script,statusand the metric data (value,rating,details,items,issues), as described inreferences/schema.md. - When
statusis"tracking", the script keeps observing the page. After the interactions, call the function named ingetDataFnwith anothermcp__chrome-devtools__evaluate_scriptcall, for examplegetINP(), and read the object it returns. - When
statusis"error"or"unsupported", readerror: the page may not have loaded yet, or the browser lacks the API.
Without Chrome DevTools MCP, run the same snippet with the webperf-snippets CLI, which loads the page in headless Chromium and prints the same result objects: npx webperf-snippets <url> --snippet <Name> --json, where <Name> is the script name without .js. It needs Playwright and Chromium (npm install --save-dev webperf-snippets playwright, then npx playwright install chromium), and tracking snippets take --interact-script <file> to drive the interactions.
