xoai/browser-check

<!-- sage-metadata cost-tier: sonnet activation: auto tags: [verification, browser, qa, smoke-test] inputs: [url, diff] outputs: [pass-fail] requires: [] -->

Browser Check (Light Mode)

Quick smoke test within quality-gates. Catches catastrophic failures: page doesn't load, JS errors, blank screen, missing key elements.

Availability Check

FIRST: Check if Lightpanda MCP tools are in the agent's tool list.

If Lightpanda MCP is NOT available:

• Return immediately
• No output, no warning, INVISIBLE
• Do NOT suggest installing Lightpanda
• Do NOT mention this gate was skipped

If the change does NOT touch frontend/user-facing code:

• Return immediately, invisible

If no running URL is known:

• Ask once: "What URL should I check? (e.g., localhost:3000)"
• If user declines or URL is unreachable, skip invisibly

When All Conditions Met

Time budget: 30 seconds max. One page load, three tool calls.

Step 1: Navigate

Use goto to load the primary affected route. If Lightpanda doesn't respond within 10 seconds, skip with timeout note.

Step 2: Check for Catastrophic Failures

1. evaluate: check for JS console errors (uncaught exceptions)
2. markdown: verify page has non-empty content (not blank/error)
3. semantic_tree: verify expected key elements exist (based on spec)

Step 3: Report

If catastrophic failure detected:

⚠ Browser check: FAIL
Route: /[path]
Issue: [what's wrong — JS error, blank page, missing elements]
Console: [relevant error output]

Recommend: Run /qa for full assessment, or /fix for this issue.

If pass:

✓ Browser check: PASS
Route: /[path] — renders, no JS errors, key elements present.

Enforcement

• Advisory ONLY — never blocks the build
• A failure produces a warning and recommendation, NOT a gate failure
• Do NOT fabricate browser findings (if you didn't load the page, don't claim you did)
• Do NOT test routes that weren't affected by the current change