| name | browser-automation |
| description | Browser automation powers web testing, scraping, and AI agent interactions. The difference between a flaky script and a reliable system comes down to understanding selectors, waiting strategies, and anti-detection patterns. |
| risk | unknown |
| source | vibeship-spawner-skills (Apache 2.0) |
| date_added | "2026-02-27T00:00:00.000Z" |
Browser Automation
Browser automation powers web testing, scraping, and AI agent interactions.
The difference between a flaky script and a reliable system comes down to
understanding selectors, waiting strategies, and anti-detection patterns.
This skill covers Playwright (recommended) and Puppeteer, with patterns for
testing, scraping, and agentic browser control. Key insight: Playwright won
the framework war. Unless you need Puppeteer's stealth ecosystem or are
Chrome-only, Playwright is the better choice in 2025.
Critical distinction: Testing automation (predictable apps you control) vs
scraping/agent automation (unpredictable sites that fight back). Different
problems, different solutions.
Principles
- Use user-facing locators (getByRole, getByText) over CSS/XPath
- Never add manual waits - Playwright's auto-wait handles it
- Each test/task should be fully isolated with fresh context
- Screenshots and traces are your debugging lifeline
- Headless for CI, headed for debugging
- Anti-detection is cat-and-mouse - stay current or get blocked
Capabilities
- browser-automation
- playwright
- puppeteer
- headless-browsers
- web-scraping
- browser-testing
- e2e-testing
- ui-automation
- selenium-alternatives
Scope
- api-testing → backend
- load-testing → performance-thinker
- accessibility-testing → accessibility-specialist
- visual-regression-testing → ui-design
Tooling
Frameworks
- Playwright - When: Default choice - cross-browser, auto-waiting, best DX Note: 96% success rate, 4.5s avg execution, Microsoft-backed
- Puppeteer - When: Chrome-only, need stealth plugins, existing codebase Note: 75% success rate at scale, but best stealth ecosystem
- Selenium - When: Legacy systems, specific language bindings Note: Slower, more verbose, but widest browser support
Stealth_tools
- puppeteer-extra-plugin-stealth - When: Need to bypass bot detection with Puppeteer Note: Gold standard for anti-detection
- playwright-extra - When: Stealth plugins for Playwright Note: Port of puppeteer-extra ecosystem
- undetected-chromedriver - When: Selenium anti-detection Note: Dynamic bypass of detection
Cloud_browsers
- Browserbase - When: Managed headless infrastructure Note: Built-in stealth mode, session management
- BrowserStack - When: Cross-browser testing at scale Note: Real devices, CI integration
Patterns
Test Isolation Pattern
Each test runs in complete isolation with fresh state
When to use: Testing, any automation that needs reproducibility
TEST ISOLATION:
"""
Each test gets its own:
- Browser context (cookies, storage)
- Fresh page
- Clean state
"""
Playwright Test Example
"""
import { test, expect } from '@playwright/test';
// Each test runs in isolated browser context
test('user can add item to cart', async ({ page }) => {
// Fresh context - no cookies, no storage from other tests
await page.goto('/products');
await page.getByRole('button', { name: 'Add to Cart' }).click();
await expect(page.getByTestId('cart-count')).toHaveText('1');
});
test('user can remove item from cart', async ({ page }) => {
// Completely isolated - cart is empty
await page.goto('/cart');
await expect(page.getByText('Your cart is empty')).toBeVisible();
});
"""
Shared Authentication Pattern
"""
// Save auth state once, reuse across tests
// setup.ts
import { test as setup } from '@playwright/test';
setup('authenticate', async ({ page }) => {
await page.goto('/login');
await page.getByLabel('Email').fill('user@example.com');
await page.getByLabel('Password').fill('password');
await page.getByRole('button', { name: 'Sign in' }).click();
// Wait for auth to complete
await page.waitForURL('/dashboard');
// Save authentication state
await page.context().storageState({
path: './playwright/.auth/user.json'
});
});
// playwright.config.ts
export default defineConfig({
projects: [
{ name: 'setup', testMatch: /.*.setup.ts/ },
{
name: 'tests',
dependencies: ['setup'],
use: {
storageState: './playwright/.auth/user.json',
},
},
],
});
"""
User-Facing Locator Pattern
Select elements the way users see them
When to use: Always - the default approach for selectors
USER-FACING LOCATORS:
"""
Priority order:
- getByRole - Best: matches accessibility tree
- getByText - Good: matches visible content
- getByLabel - Good: matches form labels
- getByTestId - Fallback: explicit test contracts
- CSS/XPath - Last resort: fragile, avoid
"""
Good Examples (User-Facing)
"""
// By role - THE BEST CHOICE
await page.getByRole('button', { name: 'Submit' }).click();
await page.getByRole('link', { name: 'Sign up' }).click();
await page.getByRole('heading', { name: 'Dashboard' }).isVisible();
await page.getByRole('textbox', { name: 'Search' }).fill('query');
// By text content
await page.getByText('Welcome back').isVisible();
await page.getByText(/Order #\d+/).click(); // Regex supported
// By label (forms)
await page.getByLabel('Email address').fill('user@example.com');
await page.getByLabel('Password').fill('secret');
// By placeholder
await page.getByPlaceholder('Search...').fill('query');
// By test ID (when no user-facing option works)
await page.getByTestId('submit-button').click();
"""
Bad Examples (Fragile)
"""
// DON'T - CSS selectors tied to structure
await page.locator('.btn-primary.submit-form').click();
await page.locator('#header > div > button:nth-child(2)').click();
// DON'T - XPath tied to structure
await page.locator('//div[@class="form"]/button[1]').click();
// DON'T - Auto-generated selectors
await page.locator('[data-v-12345]').click();
"""
Filtering and Chaining
"""
// Filter by containing text
await page.getByRole('listitem')
.filter({ hasText: 'Product A' })
.getByRole('button', { name: 'Add to cart' })
.click();
// Filter by NOT containing
await page.getByRole('listitem')
.filter({ hasNotText: 'Sold out' })
.first()
.click();
// Chain locators
const row = page.getByRole('row', { name: 'John Doe' });
await row.getByRole('button', { name: 'Edit' }).click();
"""
Auto-Wait Pattern
Let Playwright wait automatically, never add manual waits
When to use: Always with Playwright
AUTO-WAIT PATTERN:
"""
Playwright waits automatically for:
- Element to be attached to DOM
- Element to be visible
- Element to be stable (not animating)
- Element to receive events
- Element to be enabled
NEVER add manual waits!
"""
Wrong - Manual Waits
"""
// DON'T DO THIS
await page.goto('/dashboard');
await page.waitForTimeout(2000); // NO! Arbitrary wait
await page.click('.submit-button');
// DON'T DO THIS
await page.waitForSelector('.loading-spinner', { state: 'hidden' });
await page.waitForTimeout(500); // "Just to be safe" - NO!
"""
Correct - Let Auto-Wait Work
"""
// Auto-waits for button to be clickable
await page.getByRole('button', { name: 'Submit' }).click();
// Auto-waits for text to appear
await expect(page.getByText('Success!')).toBeVisible();
// Auto-waits for navigation to complete
await page.goto('/dashboard');
// Page is ready - no manual wait needed
"""
When You DO Need to Wait
"""
// Wait for specific network request
const responsePromise = page.waitForResponse(
response => response.url().includes('/api/data')
);
await page.getByRole('button', { name: 'Load' }).click();
const response = await responsePromise;
// Wait for URL change
await Promise.all([
page.waitForURL('**/dashboard'),
page.getByRole('button', { name: 'Login' }).click(),
]);
// Wait for download
const downloadPromise = page.waitForEvent('download');
await page.getByText('Export CSV').click();
const download = await downloadPromise;
"""
Stealth Browser Pattern
Avoid bot detection for scraping
When to use: Scraping sites with anti-bot protection
STEALTH BROWSER PATTERN:
"""
Bot detection checks for:
- navigator.webdriver property
- Chrome DevTools protocol artifacts
- Browser fingerprint inconsistencies
- Behavioral patterns (perfect timing, no mouse movement)
- Headless indicators
"""
Puppeteer Stealth (Best Anti-Detection)
"""
import puppeteer from 'puppeteer-extra';
import StealthPlugin from 'puppeteer-extra-plugin-stealth';
puppeteer.use(StealthPlugin());
const browser = await puppeteer.launch({
headless: 'new',
args: [
'--no-sandbox',
'--disable-setuid-sandbox',
'--disable-blink-features=AutomationControlled',
],
});
const page = await browser.newPage();
// Set realistic viewport
await page.setViewport({ width: 1920, height: 1080 });
// Realistic user agent
await page.setUserAgent(
'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 ' +
'(KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36'
);
// Navigate with human-like behavior
await page.goto('https://target-site.com', {
waitUntil: 'networkidle0',
});
"""
Playwright Stealth
"""
import { chromium } from 'playwright-extra';
import stealth from 'puppeteer-extra-plugin-stealth';
chromium.use(stealth());
const browser = await chromium.launch({ headless: true });
const context = await browser.newContext({
viewport: { width: 1920, height: 1080 },
userAgent: 'Mozilla/5.0 ...',
locale: 'en-US',
timezoneId: 'America/New_York',
});
"""
Human-Like Behavior
"""
// Random delays between actions
const randomDelay = (min: number, max: number) =>
new Promise(r => setTimeout(r, Math.random() * (max - min) + min));
await page.goto(url);
await randomDelay(500, 1500);
// Mouse movement before click
const button = await page.$('button.submit');
const box = await button.boundingBox();
await page.mouse.move(
box.x + box.width / 2,
box.y + box.height / 2,
{ steps: 10 } // Move in steps like a human
);
await randomDelay(100, 300);
await button.click();
// Scroll naturally
await page.evaluate(() => {
window.scrollBy({
top: 300 + Math.random() * 200,
behavior: 'smooth'
});
});
"""
Error Recovery Pattern
Handle failures gracefully with screenshots and retries
When to use: Any production automation
ERROR RECOVERY PATTERN:
Automatic Screenshot on Failure
"""
// playwright.config.ts
export default defineConfig({
use: {
screenshot: 'only-on-failure',
trace: 'retain-on-failure',
video: 'retain-on-failure',
},
retries: 2, // Retry failed tests
});
"""
Try-Catch with Debug Info
"""
async function scrapeProduct(page: Page, url: string) {
try {
await page.goto(url, { timeout: 30000 });
const title = await page.getByRole('heading', { level: 1 }).textContent();
const price = await page.getByTestId('price').textContent();
return { title, price, success: true };
} catch (error) {
// Capture debug info
const screenshot = await page.screenshot({
path: errors/${Date.now()}-error.png,
fullPage: true
});
const html = await page.content();
await fs.writeFile(`errors/${Date.now()}-page.html`, html);
console.error({
url,
error: error.message,
currentUrl: page.url(),
});
return { success: false, error: error.message };
}
}
"""
Retry with Exponential Backoff
"""
async function withRetry(
fn: () => Promise,
maxRetries = 3,
baseDelay = 1000
): Promise {
let lastError: Error;
for (let attempt = 0; attempt < maxRetries; attempt++) {
try {
return await fn();
} catch (error) {
lastError = error;
if (attempt < maxRetries - 1) {
const delay = baseDelay * Math.pow(2, attempt);
const jitter = delay * 0.1 * Math.random();
await new Promise(r => setTimeout(r, delay + jitter));
}
}
}
throw lastError;
}
// Usage
const result = await withRetry(
() => scrapeProduct(page, url),
3,
2000
);
"""
Parallel Execution Pattern
Run tests/tasks in parallel for speed
When to use: Multiple independent pages or tests
PARALLEL EXECUTION:
Playwright Test Parallelization
"""
// playwright.config.ts
export default defineConfig({
fullyParallel: true,
workers: process.env.CI ? 4 : undefined, // CI: 4 workers, local: CPU-based
projects: [
{ name: 'chromium', use: { ...devices['Desktop Chrome'] } },
{ name: 'firefox', use: { ...devices['Desktop Firefox'] } },
{ name: 'webkit', use: { ...devices['Desktop Safari'] } },
],
});
"""
Browser Contexts for Parallel Scraping
"""
const browser = await chromium.launch();
const urls = ['url1', 'url2', 'url3', 'url4', 'url5'];
// Create multiple contexts - each is isolated
const results = await Promise.all(
urls.map(async (url) => {
const context = await browser.newContext();
const page = await context.newPage();
try {
await page.goto(url);
const data = await extractData(page);
return { url, data, success: true };
} catch (error) {
return { url, error: error.message, success: false };
} finally {
await context.close();
}
})
);
await browser.close();
"""
Rate-Limited Parallel Processing
"""
import pLimit from 'p-limit';
const limit = pLimit(5); // Max 5 concurrent
const results = await Promise.all(
urls.map(url => limit(async () => {
const context = await browser.newContext();
const page = await context.newPage();
// Random delay between requests
await new Promise(r => setTimeout(r, Math.random() * 2000));
try {
return await scrapePage(page, url);
} finally {
await context.close();
}
}))
);
"""
Network Interception Pattern
Mock, block, or modify network requests
When to use: Testing, blocking ads/analytics, modifying responses
NETWORK INTERCEPTION:
Block Unnecessary Resources
"""
await page.route('**/*', (route) => {
const url = route.request().url();
const resourceType = route.request().resourceType();
// Block images, fonts, analytics for faster scraping
if (['image', 'font', 'media'].includes(resourceType)) {
return route.abort();
}
// Block tracking/analytics
if (url.includes('google-analytics') ||
url.includes('facebook.com/tr')) {
return route.abort();
}
return route.continue();
});
"""
Mock API Responses (Testing)
"""
await page.route('**/api/products', async (route) => {
await route.fulfill({
status: 200,
contentType: 'application/json',
body: JSON.stringify([
{ id: 1, name: 'Mock Product', price: 99.99 },
]),
});
});
// Now page will receive mocked data
await page.goto('/products');
"""
Capture API Responses
"""
const apiResponses: any[] = [];
page.on('response', async (response) => {
if (response.url().includes('/api/')) {
const data = await response.json().catch(() => null);
apiResponses.push({
url: response.url(),
status: response.status(),
data,
});
}
});
await page.goto('/dashboard');
// apiResponses now contains all API calls
"""
Sharp Edges
Using waitForTimeout Instead of Proper Waits
Severity: CRITICAL
Situation: Waiting for elements or page state
Symptoms:
Tests pass locally, fail in CI. Pass 9 times, fail on the 10th.
"Element not found" errors that seem random. Tests take 30+ seconds
when they should take 3.
Why this breaks:
waitForTimeout is a fixed delay. If the page loads in 500ms, you wait
2000ms anyway. If the page takes 2100ms (CI is slower), you fail.
There's no correct value - it's always either too short or too long.
Recommended fix:
REMOVE all waitForTimeout calls
WRONG:
await page.goto('/dashboard');
await page.waitForTimeout(2000); # Arbitrary!
await page.click('.submit');
CORRECT - Auto-wait handles it:
await page.goto('/dashboard');
await page.getByRole('button', { name: 'Submit' }).click();
If you need to wait for specific condition:
await expect(page.getByText('Dashboard')).toBeVisible();
await page.waitForURL('**/dashboard');
await page.waitForResponse(resp => resp.url().includes('/api/data'));
For animations, wait for element to be stable:
await page.getByRole('button').click(); # Auto-waits for stable
NEVER use setTimeout or waitForTimeout in production code
CSS Selectors Tied to Styling Classes
Severity: HIGH
Situation: Selecting elements for interaction
Symptoms:
Tests break after CSS refactoring. Selectors like .btn-primary stop
working. Frontend redesign breaks all tests without changing behavior.
Why this breaks:
CSS class names are implementation details for styling, not semantic
meaning. When designers change from .btn-primary to .button--primary,
your tests break even though behavior is identical.
Recommended fix:
Use user-facing locators instead:
WRONG - Tied to CSS:
await page.locator('.btn-primary.submit-form').click();
await page.locator('#sidebar > div.menu > ul > li:nth-child(3)').click();
CORRECT - User-facing:
await page.getByRole('button', { name: 'Submit' }).click();
await page.getByRole('menuitem', { name: 'Settings' }).click();
If you must use CSS, use data-testid:
Submit
await page.getByTestId('submit-order').click();
Locator priority:
1. getByRole - matches accessibility
2. getByText - matches visible content
3. getByLabel - matches form labels
4. getByTestId - explicit test contract
5. CSS/XPath - last resort only
navigator.webdriver Exposes Automation
Severity: HIGH
Situation: Scraping sites with bot detection
Symptoms:
Immediate 403 errors. CAPTCHA challenges. Empty pages. "Access Denied"
messages. Works for 1 request, then gets blocked.
Why this breaks:
By default, headless browsers set navigator.webdriver = true. This is
the first thing bot detection checks. It's a bright red flag that
says "I'm automated."
Recommended fix:
Use stealth plugins:
Puppeteer Stealth (best option):
import puppeteer from 'puppeteer-extra';
import StealthPlugin from 'puppeteer-extra-plugin-stealth';
puppeteer.use(StealthPlugin());
const browser = await puppeteer.launch({
headless: 'new',
args: ['--disable-blink-features=AutomationControlled'],
});
Playwright Stealth:
import { chromium } from 'playwright-extra';
import stealth from 'puppeteer-extra-plugin-stealth';
chromium.use(stealth());
Manual (partial):
await page.evaluateOnNewDocument(() => {
Object.defineProperty(navigator, 'webdriver', {
get: () => undefined,
});
});
Note: This is cat-and-mouse. Detection evolves.
For serious scraping, consider managed solutions like Browserbase.
Tests Share State and Affect Each Other
Severity: HIGH
Situation: Running multiple tests in sequence
Symptoms:
Tests pass individually but fail when run together. Order matters -
test B fails if test A runs first. Random failures that "fix themselves"
on rerun.
Why this breaks:
Shared browser context means shared cookies, localStorage, and session
state. Test A logs in, test B expects logged-out state. Test A adds
item to cart, test B's cart count is wrong.
Recommended fix:
Each test must be fully isolated:
Playwright Test (automatic isolation):
test('first test', async ({ page }) => {
// Fresh context, fresh page
});
test('second test', async ({ page }) => {
// Completely isolated from first test
});
Manual isolation:
const context = await browser.newContext(); // Fresh context
const page = await context.newPage();
// ... test code ...
await context.close(); // Clean up
Shared authentication (the right way):
// 1. Save auth state to file
await context.storageState({ path: './auth.json' });
// 2. Reuse in other tests
const context = await browser.newContext({
storageState: './auth.json'
});
Never modify global state in tests
Never rely on previous test's actions
No Trace Capture for CI Failures
Severity: MEDIUM
Situation: Debugging test failures in CI
Symptoms:
"Test failed in CI" with no useful information. Can't reproduce
locally. Screenshot shows page but not what went wrong. Guessing
at root cause.
Why this breaks:
CI runs headless on different hardware. Timing is different. Network
is different. Without traces, you can't see what actually happened -
the sequence of actions, network requests, console logs.
Recommended fix:
Enable traces for failures:
playwright.config.ts:
export default defineConfig({
use: {
trace: 'retain-on-failure', # Keep trace on failure
screenshot: 'only-on-failure', # Screenshot on failure
video: 'retain-on-failure', # Video on failure
},
outputDir: './test-results',
});
View trace locally:
npx playwright show-trace test-results/path/to/trace.zip
In CI, upload test-results as artifact:
GitHub Actions:
- uses: actions/upload-artifact@v3
if: failure()
with:
name: playwright-traces
path: test-results/
Trace shows:
- Timeline of actions
- Screenshots at each step
- Network requests and responses
- Console logs
- DOM snapshots
Tests Pass Headed but Fail Headless
Severity: MEDIUM
Situation: Running tests in headless mode for CI
Symptoms:
Works perfectly when you watch it. Fails mysteriously in CI.
"Element not visible" in headless but visible in headed mode.
Why this breaks:
Headless browsers have no display, which affects some CSS (visibility
calculations), viewport sizing, and font rendering. Some animations
behave differently. Popup windows may not work.
Recommended fix:
Set consistent viewport:
const browser = await chromium.launch({
headless: true,
});
const context = await browser.newContext({
viewport: { width: 1280, height: 720 },
});
Or in config:
export default defineConfig({
use: {
viewport: { width: 1280, height: 720 },
},
});
Debug headless failures:
1. Run with headed mode locally
npx playwright test --headed
2. Slow down to watch
npx playwright test --headed --slowmo 100
3. Use trace viewer for CI failures
npx playwright show-trace trace.zip
4. For stubborn issues, screenshot at failure point:
await page.screenshot({ path: 'debug.png', fullPage: true });
Getting Blocked by Rate Limiting
Severity: HIGH
Situation: Scraping multiple pages quickly
Symptoms:
Works for first 50 pages, then 429 errors. Suddenly all requests fail.
IP gets blocked. CAPTCHA starts appearing after successful requests.
Why this breaks:
Sites monitor request patterns. 100 requests per second from one IP
is obviously automated. Rate limits protect servers and catch scrapers.
Recommended fix:
Add delays between requests:
const randomDelay = () =>
new Promise(r => setTimeout(r, 1000 + Math.random() * 2000));
for (const url of urls) {
await randomDelay(); // 1-3 second delay
await page.goto(url);
// ... scrape ...
}
Use rotating proxies:
const proxies = ['http://proxy1:8080', 'http://proxy2:8080'];
let proxyIndex = 0;
const getNextProxy = () => proxies[proxyIndex++ % proxies.length];
const context = await browser.newContext({
proxy: { server: getNextProxy() },
});
Limit concurrent requests:
import pLimit from 'p-limit';
const limit = pLimit(3); // Max 3 concurrent
await Promise.all(
urls.map(url => limit(() => scrapePage(url)))
);
Rotate user agents:
const userAgents = [
'Mozilla/5.0 (Windows...',
'Mozilla/5.0 (Macintosh...',
];
await page.setExtraHTTPHeaders({
'User-Agent': userAgents[Math.floor(Math.random() * userAgents.length)]
});
New Windows/Popups Not Handled
Severity: MEDIUM
Situation: Clicking links that open new windows
Symptoms:
Click button, nothing happens. Test hangs. "Window not found" errors.
Actions succeed but verification fails because you're on wrong page.
Why this breaks:
target="_blank" links open new windows. Your page reference still
points to the original page. The new window exists but you're not
listening for it.
Recommended fix:
Wait for popup BEFORE triggering it:
New window/tab:
const pagePromise = context.waitForEvent('page');
await page.getByRole('link', { name: 'Open in new tab' }).click();
const newPage = await pagePromise;
await newPage.waitForLoadState();
// Now interact with new page
await expect(newPage.getByRole('heading')).toBeVisible();
// Close when done
await newPage.close();
Popup windows:
const popupPromise = page.waitForEvent('popup');
await page.getByRole('button', { name: 'Open popup' }).click();
const popup = await popupPromise;
await popup.waitForLoadState();
Multiple windows:
const pages = context.pages(); // Get all open pages
Can't Interact with Elements in iframes
Severity: MEDIUM
Situation: Page contains embedded iframes
Symptoms:
Element clearly visible but "not found". Selector works in DevTools
but not in Playwright. Parent page selectors work, iframe content
doesn't.
Why this breaks:
iframes are separate documents. page.locator only searches the main
frame. You need to explicitly get the iframe's frame to interact
with its contents.
Recommended fix:
Get frame by name or selector:
By frame name:
const frame = page.frame('payment-iframe');
await frame.getByRole('textbox', { name: 'Card number' }).fill('4242...');
By selector:
const frame = page.frameLocator('iframe#payment');
await frame.getByRole('textbox', { name: 'Card number' }).fill('4242...');
Nested iframes:
const outer = page.frameLocator('iframe#outer');
const inner = outer.frameLocator('iframe#inner');
await inner.getByRole('button').click();
Wait for iframe to load:
await page.waitForSelector('iframe#payment');
const frame = page.frameLocator('iframe#payment');
await frame.getByText('Secure Payment').waitFor();
Validation Checks
Using waitForTimeout
Severity: ERROR
waitForTimeout causes flaky tests and slow execution
Message: Using waitForTimeout - remove it. Playwright auto-waits for elements. Use waitForResponse, waitForURL, or assertions instead.
Using setTimeout in Test Code
Severity: WARNING
setTimeout is unreliable for timing in tests
Message: Using setTimeout instead of Playwright waits. Replace with await expect(...).toBeVisible() or page.waitFor*.
Custom Sleep Function
Severity: WARNING
Sleep functions indicate improper waiting strategy
Message: Custom sleep function detected. Use Playwright's built-in waiting mechanisms instead.
CSS Class Selector Used
Severity: WARNING
CSS class selectors are fragile
Message: Using CSS class selector. Prefer getByRole, getByText, getByLabel, or getByTestId for more stable selectors.
nth-child CSS Selector
Severity: WARNING
Position-based selectors are very fragile
Message: Using position-based selector. These break when DOM order changes. Use user-facing locators instead.
XPath Selector Used
Severity: INFO
XPath should be last resort
Message: Using XPath selector. Consider getByRole, getByText first. XPath should be last resort for complex DOM traversal.
Auto-Generated Selector
Severity: WARNING
Framework-generated selectors are extremely fragile
Message: Using auto-generated selector. These change on every build. Use data-testid instead.
Puppeteer Without Stealth Plugin
Severity: INFO
Scraping without stealth is easily detected
Message: Using Puppeteer without stealth plugin. Consider puppeteer-extra-plugin-stealth for anti-detection.
navigator.webdriver Not Hidden
Severity: INFO
navigator.webdriver exposes automation
Message: Launching browser without hiding automation flags. For scraping, add stealth measures.
Scraping Loop Without Error Handling
Severity: WARNING
One failure shouldn't crash entire scrape
Message: Scraping loop without try/catch. One page failure will crash the entire scrape. Add error handling.
Collaboration
Delegation Triggers
- user needs full desktop control beyond browser -> computer-use-agents (Desktop automation for non-browser apps)
- user needs API testing alongside browser tests -> backend (API integration and testing patterns)
- user needs testing strategy -> test-architect (Overall test architecture decisions)
- user needs visual regression testing -> ui-design (Visual comparison and design validation)
- user needs browser automation in workflows -> workflow-automation (Durable execution for browser tasks)
- user building browser tools for agents -> agent-tool-builder (Tool design patterns for LLM agents)
Related Skills
Works well with: agent-tool-builder, workflow-automation, computer-use-agents, test-architect
When to Use
- User mentions or implies: playwright
- User mentions or implies: puppeteer
- User mentions or implies: browser automation
- User mentions or implies: headless
- User mentions or implies: web scraping
- User mentions or implies: e2e test
- User mentions or implies: end-to-end
- User mentions or implies: selenium
- User mentions or implies: chromium
- User mentions or implies: browser test
- User mentions or implies: page.click
- User mentions or implies: locator
Limitations
- Use this skill only when the task clearly matches the scope described above.
- Do not treat the output as a substitute for environment-specific validation, testing, or expert review.
- Stop and ask for clarification if required inputs, permissions, safety boundaries, or success criteria are missing.
