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Use this skill to monitor a deployed URL for regressions after deploys, merges, or dependency upgrades.
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Based on SOC occupation classification
| name | canary-watch |
| description | Use this skill to monitor a deployed URL for regressions after deploys, merges, or dependency upgrades. |
| origin | ECC |
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.
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