# Web Perf

Audit, diagnose, or optimize website loading and interaction performance, Core Web...

- Repository: https://github.com/cloudflare/skills (3246 stars)
- Category: Engineering
- License: Apache-2.0
- Last updated: 2026-10-31
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add cloudflare/skills --skill web-perf -g -a claude-code -y`
Codex: `npx skills add cloudflare/skills --skill web-perf -g -a codex -y`
Cursor: `npx skills add cloudflare/skills --skill web-perf -g -a cursor -y`
Gemini CLI: `npx skills add cloudflare/skills --skill web-perf -g -a gemini-cli -y`
Claude Code plugin marketplace: `/plugin marketplace add cloudflare/skills`

## Description

Audit, diagnose, or optimize website loading and interaction performance, Core Web Vitals, and Lighthouse performance scores.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

# Web Performance Audit

Your knowledge of web performance metrics, thresholds, and tooling APIs may be outdated. **Prefer retrieval over pre-training** when citing specific numbers or recommendations.

## Retrieval Sources

| Source | How to retrieve | Use for |
|--------|----------------|---------|
| web.dev | `https://web.dev/articles/vitals` | Core Web Vitals thresholds, definitions |
| Chrome DevTools docs | `https://developer.chrome.com/docs/devtools/performance` | Tooling APIs, trace analysis |
| Lighthouse scoring | `https://developer.chrome.com/docs/lighthouse/performance/performance-scoring` | Score weights, metric thresholds |

## FIRST: Verify MCP Tools Available

Discover available browser and performance tools before starting. Use the capabilities available for the requested audit. If trace tools are unavailable, continue any useful source or network analysis and state which measurements could not be collected.

If the user wants Chrome DevTools MCP setup, consult its [installation guide](https://github.com/ChromeDevTools/chrome-devtools-mcp#quick-start) and use the latest package version. Only change MCP configuration when setup is within the user's authorized scope; otherwise ask first. For clients using `command` and `args`, an example server entry is:

```json
"chrome-devtools": {
  "command": "npx",
  "args": ["-y", "chrome-devtools-mcp@latest"]
}
```

## Key Guidelines

The rest: https://github.com/cloudflare/skills/blob/HEAD/skills/web-perf/SKILL.md