canary

Monitors deployed web apps for console errors, performance regressions, and page failures using browser screenshots.

Updated Apr 5, 2026
One-click install
npx skills add https://github.com/Simon-YHKim/eject-button --skill canary-simon-yhkim
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: canary
Source: https://github.com/Simon-YHKim/eject-button/tree/main/.claude/skills/canary
Command: npx skills add https://github.com/Simon-YHKim/eject-button --skill canary-simon-yhkim

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes references (resource) components.

What problem does it solve? Deploys that pass CI can still break in production through missing environment variables, stale CDN caches, or slow migrations. This Skill watches the live app in the first minutes after a deploy and catches regressions before users report them. ## Core Features & Use Cases - Baseline Capture: Takes pre-deploy screenshots, console error counts, and load times per page, then compares post-deploy state against them. - Continuous Monitoring Loop: Checks each monitored page every 60 seconds for a configurable duration (1-30 minutes), alerting only on changes that persist across consecutive checks. - Severity-Based Alerts: Classifies findings as CRITICAL (page load failure), HIGH (new console errors), MEDIUM (2x load time regression), or LOW (new broken links), each backed by a screenshot. - Use Case: After shipping a release, run the canary against your production URL for 10 minutes. It auto-discovers top navigation pages, watches them, and produces a health report with a HEALTHY, DEGRADED, or BROKEN verdict. ## Quick Start Ask the assistant to run the canary skill against your production URL for ten minutes after your next deploy and alert you if any page regresses.

Frequently Asked Questions about canary

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I monitor my website after a deployment?

Run the canary skill with your production URL and it checks each page every 60 seconds for a set duration. It captures screenshots, console errors, and load times, then alerts on changes that persist across two or more consecutive checks.

How to detect performance regressions after a deploy?

Capture a baseline before deploying with the --baseline flag, then run monitoring after the deploy. The skill flags any page whose load time exceeds 2x its baseline as a MEDIUM severity regression.

What is a canary baseline and why capture one before deploying?

A baseline is a saved snapshot of screenshots, console error counts, and load times per page taken before a deploy. Without it, the canary can only run a generic health check instead of detecting actual changes.

Does canary monitoring alert on every console error?

No. It alerts on changes, not absolutes. A page with three baseline errors is fine if it still has three; only new errors trigger alerts, and only if they persist across two or more consecutive checks.

Can I choose which pages the canary monitors?

Yes. Pass --pages with a comma-separated list, or let the skill auto-discover the top five internal navigation links from the homepage. You can also use --quick for a single-pass homepage check.