canary-watch
Use this skill to monitor and verify a deployed URL after releases — checks HTTP endpoints, SSE streams, static assets, console errors, and performance regressions after deploys, merges, or dependency upgrades. Smoke / canary / post-deploy verification.
How do I install this agent skill?
npx skills add https://github.com/affaan-m/ecc --skill canary-watchIs this agent skill safe to install?
- Gen Agent Trust Hubpass
The canary-watch skill facilitates post-deployment monitoring of web applications by analyzing HTTP status, performance metrics, and console errors. The primary security consideration is the indirect prompt injection surface created by processing untrusted external web content.
- Socketpass
No alerts
- Snykwarn
Risk: MEDIUM · 1 issue
What does this agent skill do?
Canary Watch — Post-Deploy Monitoring
When to Use
- After deploying to production or staging
- After merging a risky PR
- When you want to verify a fix actually fixed it
- Continuous monitoring during a launch window
- After dependency upgrades
How It Works
Monitors a deployed URL for regressions. Runs in a loop until stopped or until the watch window expires.
What It Watches
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?
7. Static Assets — are JS, CSS, image, and font requests returning 2xx/3xx with expected content types?
8. SSE Streams — do event-stream endpoints connect and receive an initial event or heartbeat?
Watch Modes
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
Alert Thresholds
critical: # immediate alert
- HTTP status != 200
- Console error count > 5 (new errors only)
- LCP > 4s
- API endpoint returns 5xx
- Static asset returns 4xx/5xx
- SSE endpoint cannot connect or drops before first heartbeat
warning: # flag in report
- LCP increased > 500ms from baseline
- CLS > 0.1
- New console warnings
- Response time > 2x baseline
- Static asset content type changed unexpectedly
- SSE heartbeat latency > 2x baseline
info: # log only
- Minor performance variance
- New network requests (third-party scripts added?)
Notifications
When a critical threshold is crossed:
- Desktop notification (macOS/Linux)
- Optional: Slack/Discord webhook
- Log to
~/.claude/canary-watch.log
Output
## 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 |
| Static assets | 42/42 ✓ | 42/42 | — |
| SSE /events | connected ✓ | connected | +80ms heartbeat |
### No regressions detected. Deploy is clean.
Integration
Pair with:
/browser-qafor pre-deploy verification- Hooks: add as a PostToolUse hook on
git pushto auto-check after deploys - CI: run in GitHub Actions after deploy step
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/canary-watch">View canary-watch on skillZs</a>