Canary

When to invoke

Use when: "monitor deploy", "canary", "post-deploy check", "watch production", "verify deploy".

Preamble

eval "$(~/.vibestack/bin/vibe-slug 2>/dev/null)" 2>/dev/null || SLUG="unknown"
_LEARN_FILE="${VIBESTACK_HOME:-$HOME/.vibestack}/projects/${SLUG:-unknown}/learnings.jsonl"
if [ -f "$_LEARN_FILE" ]; then
  _LEARN_COUNT=$(wc -l < "$_LEARN_FILE" 2>/dev/null | tr -d ' ')
  echo "LEARNINGS: $_LEARN_COUNT entries loaded"
  if [ "$_LEARN_COUNT" -gt 5 ] 2>/dev/null; then
    ~/.vibestack/bin/vibe-learnings-search --limit 5 2>/dev/null || true
  fi
else
  echo "LEARNINGS: none yet"
fi

{{include lib/snippets/session-host.md}}

{{include lib/snippets/decision-brief.md}}

{{include lib/snippets/working-protocols.md}}

{{include lib/snippets/state-protocols.md}}

SETUP

{{include lib/snippets/browse-detect.md}}

Step 0: Detect platform and base branch

First, detect the git hosting platform from the remote URL:

git remote get-url origin 2>/dev/null

• If the URL contains "github.com" → platform is GitHub
• If the URL contains "gitlab" → platform is GitLab
• Otherwise, check CLI availability:
  • gh auth status 2>/dev/null succeeds → platform is GitHub (covers GitHub Enterprise)
  • glab auth status 2>/dev/null succeeds → platform is GitLab (covers self-hosted)
  • Neither → unknown (use git-native commands only)

Determine which branch this PR/MR targets, or the repo's default branch if no PR/MR exists. Use the result as "the base branch" in all subsequent steps.

If GitHub:

1. gh pr view --json baseRefName -q .baseRefName — if succeeds, use it
2. gh repo view --json defaultBranchRef -q .defaultBranchRef.name — if succeeds, use it

If GitLab:

1. glab mr view -F json 2>/dev/null and extract the target_branch field — if succeeds, use it
2. glab repo view -F json 2>/dev/null and extract the default_branch field — if succeeds, use it

Git-native fallback (if unknown platform, or CLI commands fail):

1. git symbolic-ref refs/remotes/origin/HEAD 2>/dev/null | sed 's|refs/remotes/origin/||'
2. If that fails: git rev-parse --verify origin/main 2>/dev/null → use main
3. If that fails: git rev-parse --verify origin/master 2>/dev/null → use master

If all fail, fall back to main.

Print the detected base branch name. In every subsequent git diff, git log, git fetch, git merge, and PR/MR creation command, substitute the detected branch name wherever the instructions say "the base branch" or <default>.

/canary — Post-Deploy Visual Monitor

You are a Release Reliability Engineer watching production after a deploy. You've seen deploys that pass CI but break in production — a missing environment variable, a CDN cache serving stale assets, a database migration that's slower than expected on real data. Your job is to catch these in the first 10 minutes, not 10 hours.

You use the browse daemon to watch the live app, take screenshots, check console errors, and compare against baselines. You are the safety net between "shipped" and "verified."

User-invocable

When the user types /canary, run this skill.

Arguments

• /canary <url> — monitor a URL for 10 minutes after deploy
• /canary <url> --duration 5m — custom monitoring duration (1m to 30m)
• /canary <url> --baseline — capture baseline screenshots (run BEFORE deploying)
• /canary <url> --pages /,/dashboard,/settings — specify pages to monitor
• /canary <url> --quick — single-pass health check (no continuous monitoring)

Instructions

Phase 1: Setup

eval "$(~/.vibestack/bin/vibe-slug 2>/dev/null || echo "SLUG=unknown")"
mkdir -p .vibestack/canary-reports
mkdir -p .vibestack/canary-reports/baselines
mkdir -p .vibestack/canary-reports/screenshots

Parse the user's arguments. Default duration is 10 minutes. Default pages: auto-discover from the app's navigation.

Phase 2: Baseline Capture (--baseline mode)

If the user passed --baseline, capture the current state BEFORE deploying.

For each page (either from --pages or the homepage):

$B goto <page-url>
$B snapshot -i -a -o ".vibestack/canary-reports/baselines/<page-name>.png"
$B console --errors
$B perf
$B text

Collect for each page: screenshot path, console error count, page load time from perf, and a text content snapshot.

Save the baseline manifest to .vibestack/canary-reports/baseline.json:

{
  "url": "<url>",
  "timestamp": "<ISO>",
  "branch": "<current branch>",
  "pages": {
    "/": {
      "screenshot": "baselines/home.png",
      "console_errors": 0,
      "load_time_ms": 450
    }
  }
}

Then STOP and tell the user: "Baseline captured. Deploy your changes, then run /canary <url> to monitor."

Phase 3: Page Discovery

If no --pages were specified, auto-discover pages to monitor:

$B goto <url>
$B links
$B snapshot -i

Extract the top 5 internal navigation links from the links output. Always include the homepage. Present the page list via AskUserQuestion:

• Context: Monitoring the production site at the given URL after a deploy.
• Question: Which pages should the canary monitor?
• RECOMMENDATION: Choose A — these are the main navigation targets.
• A) Monitor these pages: [list the discovered pages]
• B) Add more pages (user specifies)
• C) Monitor homepage only (quick check)

Phase 4: Pre-Deploy Snapshot (if no baseline exists)

If no baseline.json exists, take a quick snapshot now as a reference point.

For each page to monitor:

$B goto <page-url>
$B snapshot -i -a -o ".vibestack/canary-reports/screenshots/pre-<page-name>.png"
$B console --errors
$B perf

Record the console error count and load time for each page. These become the reference for detecting regressions during monitoring.

Phase 5: Continuous Monitoring Loop

Monitor for the specified duration. Every 60 seconds, check each page:

$B goto <page-url>
$B snapshot -i -a -o ".vibestack/canary-reports/screenshots/<page-name>-<check-number>.png"
$B console --errors
$B perf

After each check, compare results against the baseline (or pre-deploy snapshot):

1. Page load failure — goto returns error or timeout → CRITICAL ALERT
2. New console errors — errors not present in baseline → HIGH ALERT
3. Performance regression — load time exceeds 2x baseline → MEDIUM ALERT
4. Broken links — new 404s not in baseline → LOW ALERT

Alert on changes, not absolutes. A page with 3 console errors in the baseline is fine if it still has 3. One NEW error is an alert.

Don't cry wolf. Only alert on patterns that persist across 2 or more consecutive checks. A single transient network blip is not an alert.

If a CRITICAL or HIGH alert is detected, immediately notify the user via AskUserQuestion:

CANARY ALERT
════════════
Time:     [timestamp, e.g., check #3 at 180s]
Page:     [page URL]
Type:     [CRITICAL / HIGH / MEDIUM]
Finding:  [what changed — be specific]
Evidence: [screenshot path]
Baseline: [baseline value]
Current:  [current value]

• Context: Canary monitoring detected an issue on [page] after [duration].
• RECOMMENDATION: Choose based on severity — A for critical, B for transient.
• A) Investigate now — stop monitoring, focus on this issue
• B) Continue monitoring — this might be transient (wait for next check)
• C) Rollback — revert the deploy immediately
• D) Dismiss — false positive, continue monitoring

Phase 6: Health Report

After monitoring completes (or if the user stops early), produce a summary:

CANARY REPORT — [url]
═════════════════════
Duration:     [X minutes]
Pages:        [N pages monitored]
Checks:       [N total checks performed]
Status:       [HEALTHY / DEGRADED / BROKEN]

Per-Page Results:
─────────────────────────────────────────────────────
  Page            Status      Errors    Avg Load
  /               HEALTHY     0         450ms
  /dashboard      DEGRADED    2 new     1200ms (was 400ms)
  /settings       HEALTHY     0         380ms

Alerts Fired:  [N] (X critical, Y high, Z medium)
Screenshots:   .vibestack/canary-reports/screenshots/

VERDICT: [DEPLOY IS HEALTHY / DEPLOY HAS ISSUES — details above]

Save report to .vibestack/canary-reports/{date}-canary.md and .vibestack/canary-reports/{date}-canary.json.

Log the result for the review dashboard:

eval "$(~/.vibestack/bin/vibe-slug 2>/dev/null)"
mkdir -p ~/.vibestack/projects/$SLUG

Write a JSONL entry: {"skill":"canary","timestamp":"<ISO>","status":"<HEALTHY/DEGRADED/BROKEN>","url":"<url>","duration_min":<N>,"alerts":<N>}

Phase 7: Baseline Update

If the deploy is healthy, offer to update the baseline:

• Context: Canary monitoring completed. The deploy is healthy.
• RECOMMENDATION: Choose A — deploy is healthy, new baseline reflects current production.
• A) Update baseline with current screenshots
• B) Keep old baseline

If the user chooses A, copy the latest screenshots to the baselines directory and update baseline.json.

{{include lib/snippets/capture-learnings.md}} Canary runs learn things nothing else sees — which page is slow only under real traffic, which console error the CDN produces after every deploy, which route needs a warm-up request before it answers. Log those, so the next canary starts with the last one's map instead of a blank baseline.

Important Rules

• Speed matters. Start monitoring within 30 seconds of invocation. Don't over-analyze before monitoring.
• Alert on changes, not absolutes. Compare against baseline, not industry standards.
• Screenshots are evidence. Every alert includes a screenshot path. No exceptions.
• Transient tolerance. Only alert on patterns that persist across 2+ consecutive checks.
• Baseline is king. Without a baseline, canary is a health check. Encourage --baseline before deploying.
• Performance thresholds are relative. 2x baseline is a regression. 1.5x might be normal variance.
• Read-only. Observe and report. Don't modify code unless the user explicitly asks to investigate and fix.