benchmark
Use this skill to measure performance baselines, detect regressions before/after PRs, and compare stack alternatives.
How do I install this agent skill?
npx skills add https://github.com/affaan-m/ecc --skill benchmarkIs this agent skill safe to install?
- Gen Agent Trust Hubpass
The benchmark skill is safe for its intended purpose of performance measurement. It contains a minor vulnerability surface for indirect prompt injection as it processes content from external web pages and API responses without explicit sanitization or boundary markers.
- Socketpass
No alerts
- Snykwarn
Risk: MEDIUM · 1 issue
What does this agent skill do?
Benchmark — Performance Baseline & Regression Detection
When to Use
- Before and after a PR to measure performance impact
- Setting up performance baselines for a project
- When users report "it feels slow"
- Before a launch — ensure you meet performance targets
- Comparing your stack against alternatives
How It Works
Mode 1: Page Performance
Measures real browser metrics via browser MCP:
1. Navigate to each target URL
2. Measure Core Web Vitals:
- LCP (Largest Contentful Paint) — target < 2.5s
- CLS (Cumulative Layout Shift) — target < 0.1
- INP (Interaction to Next Paint) — target < 200ms
- FCP (First Contentful Paint) — target < 1.8s
- TTFB (Time to First Byte) — target < 800ms
3. Measure resource sizes:
- Total page weight (target < 1MB)
- JS bundle size (target < 200KB gzipped)
- CSS size
- Image weight
- Third-party script weight
4. Count network requests
5. Check for render-blocking resources
Mode 2: API Performance
Benchmarks API endpoints:
1. Hit each endpoint 100 times
2. Measure: p50, p95, p99 latency
3. Track: response size, status codes
4. Test under load: 10 concurrent requests
5. Compare against SLA targets
Mode 3: Build Performance
Measures development feedback loop:
1. Cold build time
2. Hot reload time (HMR)
3. Test suite duration
4. TypeScript check time
5. Lint time
6. Docker build time
Mode 4: Before/After Comparison
Run before and after a change to measure impact:
/benchmark baseline # saves current metrics
# ... make changes ...
/benchmark compare # compares against baseline
Output:
| Metric | Before | After | Delta | Verdict |
|--------|--------|-------|-------|---------|
| LCP | 1.2s | 1.4s | +200ms | WARNING: WARN |
| Bundle | 180KB | 175KB | -5KB | ✓ BETTER |
| Build | 12s | 14s | +2s | WARNING: WARN |
Output
Stores baselines in .ecc/benchmarks/ as JSON. Git-tracked so the team shares baselines.
Integration
- CI: run
/benchmark compareon every PR - Pair with
/canary-watchfor post-deploy monitoring - Pair with
/browser-qafor full pre-ship checklist
How can the creator link this skill?
Add the canonical catalog link to the repository README so users can inspect current installs and available audits. The publishing guide covers the complete discovery path.
<a href="https://skillzs.dev/skills/affaan-m/ecc/benchmark">View benchmark on skillZs</a>