Ops: Performance Skill | Agent Skills

Ops: Performance

Analyze application performance.

Argument: $ARGUMENTS — analysis type (lighthouse, bundle, k6, all; default: all) and optional target environment

Path Convention

Frontend: Current project directory (.)
Backend: ${BACKEND_DIR:-../backend-v2} — set BACKEND_DIR in .claude/settings.local.json if your backend is elsewhere

Discovery

Read frontend package.json for lighthouse:check, export:web, analyze:bundle scripts
Read backend package.json for k6:* scripts
Read e2e/constants.ts or .env.* files for environment URLs

Lighthouse Audit

Against Local

npx lighthouse http://localhost:8081 \
  --output=json \
  --output-path=./lighthouse-local.json \
  --chrome-flags='--headless --no-sandbox'

Against Deployed Environment

Discover frontend URLs from e2e/constants.ts or .env.* files:

npx lighthouse https://{env_url} \
  --output=json \
  --output-path=./lighthouse-{env}.json \
  --chrome-flags='--headless --no-sandbox'

LHCI (Lighthouse CI — uses project config)

bun run lighthouse:check

Parse Lighthouse Results

cat lighthouse-{env}.json | jq '{
  performance: .categories.performance.score,
  accessibility: .categories.accessibility.score,
  bestPractices: .categories["best-practices"].score,
  seo: .categories.seo.score,
  fcp: .audits["first-contentful-paint"].displayValue,
  lcp: .audits["largest-contentful-paint"].displayValue,
  tbt: .audits["total-blocking-time"].displayValue,
  cls: .audits["cumulative-layout-shift"].displayValue,
  si: .audits["speed-index"].displayValue
}'

Bundle Analysis

Full Analysis (export + source-map-explorer)

bun run export:web && bun run analyze:bundle

Quick Size Check

bun run export:web
echo "=== Total Bundle Size ==="
du -sh dist/
echo ""
echo "=== Largest JS Files ==="
find dist -name "*.js" -exec ls -lhS {} + 2>/dev/null | head -20

k6 Load Tests

Discover available k6 scripts from the backend package.json (matching k6:*).

Smoke Test (minimal load, verify endpoints work)

cd "${BACKEND_DIR:-../backend-v2}"
bun run k6:smoke

Load Test (normal traffic simulation)

cd "${BACKEND_DIR:-../backend-v2}"
bun run k6:load

Stress Test (push beyond normal capacity)

cd "${BACKEND_DIR:-../backend-v2}"
bun run k6:stress

Spike Test (sudden traffic burst)

cd "${BACKEND_DIR:-../backend-v2}"
bun run k6:spike

Docker-based k6 (no local k6 install needed)

cd "${BACKEND_DIR:-../backend-v2}"
bun run k6:docker:smoke
bun run k6:docker:load

Output Format

Lighthouse Scores

| Metric | Score | Rating | |--------|-------|--------| | Performance | 0.85 | GOOD | | Accessibility | 0.92 | GOOD | | Best Practices | 0.88 | GOOD | | SEO | 0.95 | GOOD |

Core Web Vitals

| Metric | Value | Threshold | Status | |--------|-------|-----------|--------| | FCP (First Contentful Paint) | 1.2s | < 1.8s | PASS | | LCP (Largest Contentful Paint) | 2.1s | < 2.5s | PASS | | TBT (Total Blocking Time) | 150ms | < 200ms | PASS | | CLS (Cumulative Layout Shift) | 0.05 | < 0.1 | PASS |

Bundle Size

| Category | Size | Notes | |----------|------|-------| | Total dist/ | 4.2 MB | | | Largest chunk | 1.1 MB | vendor.js |

k6 Results

| Metric | Value | |--------|-------| | Requests/sec | 450 | | Avg response time | 120ms | | p95 response time | 350ms | | Error rate | 0.1% |

Include recommendations for any metrics that fall below thresholds.

Agent Skills: Ops: Performance

Install this agent skill to your local

Skill Files