console-error-scan

Console Error Scanner

Find JS errors and failed requests hiding in the browser console. No signup required.

Prerequisites

• Playwright MCP (comes with Claude Code)

Trigger

• "Check for console errors on https://..."
• "Find JS errors on my site"
• "Any broken requests on this page?"

Workflow

1. Navigate to the URL using mcp__playwright__browser_navigate
2. Collect console messages with mcp__playwright__browser_console_messages
3. Collect network failures with mcp__playwright__browser_network_requests
4. Click through 3-5 main navigation links and repeat collection
5. Categorize findings:

Categories

• JS Errors — uncaught exceptions, type errors, reference errors
• Failed Requests — 4xx/5xx responses, CORS errors, timeouts
• Deprecation Warnings — deprecated API usage
• Mixed Content — HTTP resources on HTTPS page
• CSP Violations — blocked by Content Security Policy

1. Output:

## Console Health: [URL]

**Pages checked: 4** | **Errors: 5** | **Warnings: 3**

### Errors
1. [JS] TypeError: Cannot read property 'map' of undefined
   - Page: /dashboard
   - Source: app.bundle.js:234

2. [NETWORK] GET /api/user/preferences — 500 Internal Server Error
   - Page: /settings

3. [NETWORK] GET /fonts/custom.woff2 — 404
   - Page: all pages (loaded in header)

### Warnings
1. [DEPRECATION] document.domain setter is deprecated
2. [MIXED CONTENT] Loading HTTP image on HTTPS page

### Clean Pages
- /about — no errors
- /pricing — no errors

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