| name | web-tests |
| description | Complete browser automation with Playwright. **ALWAYS use when user needs browser testing, E2E testing, screenshots, form testing, or responsive design validation.** Auto-detects dev servers, saves test scripts to working directory. Examples - "test this page", "take screenshots of responsive design", "test login flow", "check for broken links", "validate form submission". |
IMPORTANT - Path Resolution:
This skill is installed globally but saves outputs to the user's working directory. Always pass CWD environment variable when executing commands to ensure outputs go to the correct location.
Common installation paths:
- Plugin system:
~/.claude/plugins/marketplaces/claude-craftkit/plugins/ui-tests/skills/web-tests - Manual global:
~/.claude/skills/web-tests - Project-specific:
<project>/.claude/skills/web-tests
Web Testing & Browser Automation
General-purpose browser automation skill. I'll write custom Playwright code for any automation task you request and execute it via the universal executor.
CRITICAL WORKFLOW - Follow these steps in order:
Auto-detect dev servers - For localhost testing, ALWAYS run server detection FIRST:
cd $SKILL_DIR && node -e "require('./lib/helpers').detectDevServers().then(servers => console.log(JSON.stringify(servers)))"- If 1 server found: Use it automatically, inform user
- If multiple servers found: Ask user which one to test
- If no servers found: Ask for URL or offer to help start dev server
Write scripts to user's working directory - Save to
.web-tests/scripts/test-*.jsin user's repoUse visible browser by default - Always use
headless: falseunless user specifically requests headless modeParameterize URLs - Always make URLs configurable via constant at top of script
How It Works
- You describe what you want to test/automate
- I auto-detect running dev servers (or ask for URL if testing external site)
- I write custom Playwright code in
.web-tests/scripts/test-*.js(in user's working directory) - I execute it via:
CWD=$(pwd) cd $SKILL_DIR && node run.js .web-tests/scripts/test-*.js - Results displayed in real-time, browser window visible for debugging
- Screenshots automatically saved to
.web-tests/screenshots/
Setup (First Time)
cd $SKILL_DIR
npm run setup
This installs Playwright and Chromium browser. Only needed once.
Execution Pattern
Step 1: Detect dev servers (for localhost testing)
cd $SKILL_DIR && node -e "require('./lib/helpers').detectDevServers().then(s => console.log(JSON.stringify(s)))"
Step 2: Write test script to user's .web-tests/scripts/ with URL parameter
// .web-tests/scripts/test-page.js
const { chromium } = require("playwright");
// Parameterized URL (detected or user-provided)
const TARGET_URL = "http://localhost:3001"; // <-- Auto-detected or from user
(async () => {
const browser = await chromium.launch({ headless: false });
const page = await browser.newPage();
await page.goto(TARGET_URL);
console.log("Page loaded:", await page.title());
await page.screenshot({
path: ".web-tests/screenshots/page.png",
fullPage: true,
});
console.log("📸 Screenshot saved to .web-tests/screenshots/page.png");
await browser.close();
})();
Step 3: Execute from skill directory with CWD
CWD=$(pwd) cd $SKILL_DIR && node run.js $(pwd)/.web-tests/scripts/test-page.js
Common Patterns
Test a Page (Multiple Viewports)
// .web-tests/scripts/test-responsive.js
const { chromium } = require("playwright");
const helpers = require("$SKILL_DIR/lib/helpers"); // Path will be resolved
const TARGET_URL = "http://localhost:3001"; // Auto-detected
(async () => {
const browser = await chromium.launch({ headless: false, slowMo: 100 });
const page = await browser.newPage();
// Desktop test
await page.setViewportSize({ width: 1920, height: 1080 });
await page.goto(TARGET_URL);
console.log("Desktop - Title:", await page.title());
await helpers.takeScreenshot(page, "desktop"); // Saves to .web-tests/screenshots/
// Mobile test
await page.setViewportSize({ width: 375, height: 667 });
await helpers.takeScreenshot(page, "mobile");
await browser.close();
})();
Test Login Flow
// .web-tests/scripts/test-login.js
const { chromium } = require("playwright");
const TARGET_URL = "http://localhost:3001"; // Auto-detected
(async () => {
const browser = await chromium.launch({ headless: false });
const page = await browser.newPage();
await page.goto(`${TARGET_URL}/login`);
await page.fill('input[name="email"]', "test@example.com");
await page.fill('input[name="password"]', "password123");
await page.click('button[type="submit"]');
// Wait for redirect
await page.waitForURL("**/dashboard");
console.log("✅ Login successful, redirected to dashboard");
await browser.close();
})();
Fill and Submit Form
// .web-tests/scripts/test-form.js
const { chromium } = require("playwright");
const helpers = require("$SKILL_DIR/lib/helpers");
const TARGET_URL = "http://localhost:3001"; // Auto-detected
(async () => {
const browser = await chromium.launch({ headless: false, slowMo: 50 });
const page = await browser.newPage();
await page.goto(`${TARGET_URL}/contact`);
await page.fill('input[name="name"]', "John Doe");
await page.fill('input[name="email"]', "john@example.com");
await page.fill('textarea[name="message"]', "Test message");
await helpers.takeScreenshot(page, "form-filled");
await page.click('button[type="submit"]');
// Verify submission
await page.waitForSelector(".success-message");
console.log("✅ Form submitted successfully");
await helpers.takeScreenshot(page, "form-success");
await browser.close();
})();
Check for Broken Links
// .web-tests/scripts/test-broken-links.js
const { chromium } = require("playwright");
const TARGET_URL = "http://localhost:3001";
(async () => {
const browser = await chromium.launch({ headless: false });
const page = await browser.newPage();
await page.goto(TARGET_URL);
const links = await page.locator('a[href^="http"]').all();
const results = { working: 0, broken: [] };
for (const link of links) {
const href = await link.getAttribute("href");
try {
const response = await page.request.head(href);
if (response.ok()) {
results.working++;
} else {
results.broken.push({ url: href, status: response.status() });
}
} catch (e) {
results.broken.push({ url: href, error: e.message });
}
}
console.log(`✅ Working links: ${results.working}`);
console.log(`❌ Broken links:`, results.broken);
await browser.close();
})();
Take Screenshot with Error Handling
// .web-tests/scripts/screenshot-with-error-handling.js
const { chromium } = require("playwright");
const helpers = require("$SKILL_DIR/lib/helpers");
const TARGET_URL = "http://localhost:3001";
(async () => {
const browser = await chromium.launch({ headless: false });
const page = await browser.newPage();
try {
await page.goto(TARGET_URL, {
waitUntil: "networkidle",
timeout: 10000,
});
await helpers.takeScreenshot(page, "page-success");
console.log("📸 Screenshot saved successfully");
} catch (error) {
console.error("❌ Error:", error.message);
await helpers.takeScreenshot(page, "page-error");
} finally {
await browser.close();
}
})();
Test Responsive Design (Full)
// .web-tests/scripts/test-responsive-full.js
const { chromium } = require("playwright");
const helpers = require("$SKILL_DIR/lib/helpers");
const TARGET_URL = "http://localhost:3001"; // Auto-detected
(async () => {
const browser = await chromium.launch({ headless: false });
const page = await browser.newPage();
const viewports = [
{ name: "Desktop", width: 1920, height: 1080 },
{ name: "Tablet", width: 768, height: 1024 },
{ name: "Mobile", width: 375, height: 667 },
];
for (const viewport of viewports) {
console.log(
`Testing ${viewport.name} (${viewport.width}x${viewport.height})`
);
await page.setViewportSize({
width: viewport.width,
height: viewport.height,
});
await page.goto(TARGET_URL);
await page.waitForTimeout(1000);
await helpers.takeScreenshot(page, viewport.name.toLowerCase());
}
console.log("✅ All viewports tested");
await browser.close();
})();
Inline Execution (Simple Tasks)
For quick one-off tasks, you can execute code inline without creating files:
# Take a quick screenshot
cd $SKILL_DIR && CWD=$(pwd) node run.js "
const browser = await chromium.launch({ headless: false });
const page = await browser.newPage();
await page.goto('http://localhost:3001');
await helpers.takeScreenshot(page, 'quick-test');
console.log('Screenshot saved');
await browser.close();
"
When to use inline vs files:
- Inline: Quick one-off tasks (screenshot, check if element exists, get page title)
- Files: Complex tests, responsive design checks, anything user might want to re-run
Available Helpers
Optional utility functions in lib/helpers.js:
const helpers = require("./lib/helpers");
// Detect running dev servers (CRITICAL - use this first!)
const servers = await helpers.detectDevServers();
console.log("Found servers:", servers);
// Safe click with retry
await helpers.safeClick(page, "button.submit", { retries: 3 });
// Safe type with clear
await helpers.safeType(page, "#username", "testuser");
// Take timestamped screenshot (auto-saves to .web-tests/screenshots/)
await helpers.takeScreenshot(page, "test-result");
// Handle cookie banners
await helpers.handleCookieBanner(page);
// Extract table data
const data = await helpers.extractTableData(page, "table.results");
See lib/helpers.js for full list.
Directory Structure
When testing, the skill creates this structure in the user's working directory:
user-repo/
└── .web-tests/
├── scripts/ # Test scripts (reusable)
│ ├── test-login.js
│ ├── test-form.js
│ ├── test-responsive.js
│ └── test-broken-links.js
└── screenshots/ # Screenshots with timestamps
├── desktop-2025-10-23T12-30-45.png
├── mobile-2025-10-23T12-30-51.png
└── form-success-2025-10-23T12-31-05.png
Tips
- CRITICAL: Detect servers FIRST - Always run
detectDevServers()before writing test code for localhost testing - Save to .web-tests/ - Write scripts to
.web-tests/scripts/, screenshots auto-save to.web-tests/screenshots/ - Parameterize URLs - Put detected/provided URL in a
TARGET_URLconstant at the top of every script - DEFAULT: Visible browser - Always use
headless: falseunless user explicitly asks for headless mode - Headless mode - Only use
headless: truewhen user specifically requests "headless" or "background" execution - Slow down: Use
slowMo: 100to make actions visible and easier to follow - Wait strategies: Use
waitForURL,waitForSelector,waitForLoadStateinstead of fixed timeouts - Error handling: Always use try-catch for robust automation
- Console output: Use
console.log()to track progress and show what's happening - Use helpers: The
helpers.takeScreenshot()automatically saves to.web-tests/screenshots/
Troubleshooting
Playwright not installed:
cd $SKILL_DIR && npm run setup
Module not found:
Ensure running from skill directory via run.js wrapper with CWD set
Browser doesn't open:
Check headless: false and ensure display available
Element not found:
Add wait: await page.waitForSelector('.element', { timeout: 10000 })
Screenshots not in .web-tests/:
Make sure CWD environment variable is set when executing
Example Usage
User: "Test if the marketing page looks good"
Claude: I'll test the marketing page across multiple viewports. Let me first detect running servers...
[Runs: detectDevServers()]
[Output: Found server on port 3001]
I found your dev server running on http://localhost:3001
[Writes custom automation script to .web-tests/scripts/test-marketing.js with URL parameterized]
[Runs: CWD=$(pwd) cd $SKILL_DIR && node run.js .web-tests/scripts/test-marketing.js]
[Shows results with screenshots from .web-tests/screenshots/]
User: "Check if login redirects correctly"
Claude: I'll test the login flow. First, let me check for running servers...
[Runs: detectDevServers()]
[Output: Found servers on ports 3000 and 3001]
I found 2 dev servers. Which one should I test?
- http://localhost:3000
- http://localhost:3001
User: "Use 3001"
[Writes login automation to .web-tests/scripts/test-login.js]
[Runs: CWD=$(pwd) cd $SKILL_DIR && node run.js .web-tests/scripts/test-login.js]
[Reports: ✅ Login successful, redirected to /dashboard]
Notes
- Each automation is custom-written for your specific request
- Not limited to pre-built scripts - any browser task possible
- Auto-detects running dev servers to eliminate hardcoded URLs
- Test scripts saved to
.web-tests/scripts/for reusability - Screenshots automatically saved to
.web-tests/screenshots/with timestamps - Code executes reliably with proper module resolution via
run.js - Works as global tool - no per-repo installation needed