MCP Tools¶
The server exposes two tools to your AI assistant.
| Tool | Description |
|---|---|
analyze_page |
Analyze a single URL with PageSpeed Insights |
analyze_pages |
Analyze multiple URLs in a single call |
Strategy Parameter¶
Both tools accept an optional strategy parameter:
| Value | What it does |
|---|---|
"mobile" |
Runs a mobile Lighthouse analysis (default) |
"desktop" |
Runs a desktop Lighthouse analysis |
"both" |
Runs mobile then desktop -- two sequential API calls |
strategy=\"both\" doubles latency
The PSI API takes 5-20+ seconds per URL. Using strategy="both" makes two back-to-back calls. On a slow or complex page, this can exceed your MCP client's timeout. Prefer "mobile" or "desktop" for interactive use unless you specifically need both strategies.
Core Web Vitals Thresholds¶
Google's official thresholds for each metric:
| Metric | Good | Needs Improvement | Poor |
|---|---|---|---|
| LCP (Largest Contentful Paint) | < 2.5s | 2.5s - 4.0s | > 4.0s |
| CLS (Cumulative Layout Shift) | < 0.1 | 0.1 - 0.25 | > 0.25 |
| FCP (First Contentful Paint) | < 1.8s | 1.8s - 3.0s | > 3.0s |
| TTFB (Time to First Byte) | < 0.8s | 0.8s - 1.8s | > 1.8s |
| TBT (Total Blocking Time) | < 200ms | 200ms - 600ms | > 600ms |
| Speed Index | < 3.4s | 3.4s - 5.8s | > 5.8s |
The analyze_page and analyze_pages tools return the numeric value and the rating field ("good", "needs-improvement", or "poor") for each metric.