web-perf

Measures Core Web Vitals and identifies render-blocking resources, network chains, layout shifts, and caching issues. Your knowledge of web performance metrics, thresholds, and tooling APIs may be outdated. Prefer retrieval over pre-training when citing specific numbers or recommendations. Run this before starting. Try calling navigate_page or performance_start_trace . If unavailable, STOP—the chrome-devtools MCP server isn't configured. Ask the user to add this to their MCP config: Copy this checklist to track progress: Navigate to the target URL: Start a performance trace with reload to capture cold-load metrics: Wait for trace completion, then retrieve results. Troubleshooting: Use performance_analyze_insight to extract key metrics.