From awesome-claude-notes
Monitors deployed web app URLs for post-deploy regressions including HTTP status, console errors, network failures, performance metrics (LCP/CLS/INP), content changes, and API health with alerts and looping checks.
npx claudepluginhub loulanyue/awesome-claude-notes --plugin awesome-claude-notesThis skill uses the workspace's default tool permissions.
- After deploying to production or staging
Enforces C++ Core Guidelines for writing, reviewing, and refactoring modern C++ code (C++17+), promoting RAII, immutability, type safety, and idiomatic practices.
Provides patterns for shared UI in Compose Multiplatform across Android, iOS, Desktop, and Web: state management with ViewModels/StateFlow, navigation, theming, and performance.
Implements Playwright E2E testing patterns: Page Object Model, test organization, configuration, reporters, artifacts, and CI/CD integration for stable suites.
Monitors a deployed URL for regressions. Runs in a loop until stopped or until the watch window expires.
1. HTTP Status — is the page returning 200?
2. Console Errors — new errors that weren't there before?
3. Network Failures — failed API calls, 5xx responses?
4. Performance — LCP/CLS/INP regression vs baseline?
5. Content — did key elements disappear? (h1, nav, footer, CTA)
6. API Health — are critical endpoints responding within SLA?
Quick check (default): single pass, report results
/canary-watch https://myapp.com
Sustained watch: check every N minutes for M hours
/canary-watch https://myapp.com --interval 5m --duration 2h
Diff mode: compare staging vs production
/canary-watch --compare https://staging.myapp.com https://myapp.com
critical: # immediate alert
- HTTP status != 200
- Console error count > 5 (new errors only)
- LCP > 4s
- API endpoint returns 5xx
warning: # flag in report
- LCP increased > 500ms from baseline
- CLS > 0.1
- New console warnings
- Response time > 2x baseline
info: # log only
- Minor performance variance
- New network requests (third-party scripts added?)
When a critical threshold is crossed:
~/.claude/canary-watch.log## Canary Report — myapp.com — 2026-03-23 03:15 PST
### Status: HEALTHY ✓
| Check | Result | Baseline | Delta |
|-------|--------|----------|-------|
| HTTP | 200 ✓ | 200 | — |
| Console errors | 0 ✓ | 0 | — |
| LCP | 1.8s ✓ | 1.6s | +200ms |
| CLS | 0.01 ✓ | 0.01 | — |
| API /health | 145ms ✓ | 120ms | +25ms |
### No regressions detected. Deploy is clean.
Pair with:
/browser-qa for pre-deploy verificationgit push to auto-check after deploys