Puppeteer

Setup

On first use, read setup.md for integration guidelines.

When to Use

User needs browser automation: web scraping, E2E testing, PDF generation, screenshots, or any headless Chrome task. Agent handles page navigation, element interaction, waiting strategies, and data extraction.

Architecture

Scripts and outputs in ~/puppeteer/. See memory-template.md for structure.

~/puppeteer/
├── memory.md       # Status + preferences
├── scripts/        # Reusable automation scripts
└── output/         # Screenshots, PDFs, scraped data

Quick Reference

Core Rules

1. Always Wait Before Acting

Never click or type immediately after navigation. Always wait for the element:

await page.waitForSelector('#button');
await page.click('#button');

Clicking without waiting causes "element not found" errors 90% of the time.

2. Use Specific Selectors

Prefer stable selectors in this order:

1. [data-testid="submit"] — test attributes (most stable)
2. #unique-id — IDs
3. form button[type="submit"] — semantic combinations
4. .class-name — classes (least stable, changes often)

Avoid: div > div > div > button — breaks on any DOM change.

3. Handle Navigation Explicitly

After clicks that navigate, wait for navigation:

await Promise.all([
  page.waitForNavigation(),
  page.click('a.next-page')
]);

Without this, the script continues before the new page loads.

4. Set Realistic Viewport

Always set viewport for consistent rendering:

await page.setViewport({ width: 1280, height: 800 });

Default viewport is 800x600 — many sites render differently or show mobile views.

5. Handle Popups and Dialogs

Dismiss dialogs before they block interaction:

page.on('dialog', async dialog => {
  await dialog.dismiss(); // or dialog.accept()
});

Unhandled dialogs freeze the script.

6. Close Browser on Errors

Always wrap in try/finally:

const browser = await puppeteer.launch();
try {
  // ... automation code
} finally {
  await browser.close();
}

Leaked browser processes consume memory and ports.

7. Respect Rate Limits

Add delays between requests to avoid blocks:

await page.waitForTimeout(1000 + Math.random() * 2000);

Hammering sites triggers CAPTCHAs and IP bans.

Common Traps

• page.click() on invisible element → fails silently, use waitForSelector with visible: true
• Screenshots of elements off-screen → blank image, scroll into view first
• page.evaluate() returns undefined → cannot return DOM nodes, only serializable data
• Headless blocked by site → use headless: 'new' or set user agent
• Form submit reloads page → page.waitForNavigation() or data is lost
• Shadow DOM elements invisible to selectors → use page.evaluateHandle() to pierce shadow roots
• Cookies not persisting → launch with userDataDir for session persistence

Security & Privacy

Data that stays local:

• All scraped data in ~/puppeteer/output/
• Browser profile in specified userDataDir

This skill does NOT:

• Send scraped data anywhere
• Store credentials (you provide them per-script)
• Access files outside ~/puppeteer/

Related Skills

Install with clawhub install <slug> if user confirms:

• playwright — Cross-browser automation alternative
• chrome — Chrome DevTools and debugging
• web — General web development

Feedback

• If useful: clawhub star puppeteer
• Stay updated: clawhub sync