arklabshq/browser-testing

Browser Testing Skill

USE WHEN

• User asks to test a web application or user interface
• User needs to debug UI/frontend issues visually
• User wants to capture screenshots of a webpage
• User needs to automate browser interactions (clicks, form fills)
• User asks to validate responsive design or cross-browser behavior
• User wants to test user workflows end-to-end

CAPABILITIES

This skill provides browser automation through Playwright MCP:

• Visual Debugging: Capture screenshots and visual state
• DOM Interaction: Click elements, fill forms, navigate pages
• Content Extraction: Get page HTML, extract text/data
• Responsive Testing: Test different viewport sizes
• User Flow Automation: Complete multi-step workflows
• Debug Assistance: Inspect elements, check CSS/JS rendering

MCP TOOLS AVAILABLE

All Playwright MCP tools are prefixed with mcp__playwright_*. Common tools include:

Navigation & Screenshots

# Navigate to a page and capture screenshot
mcp__playwright_navigate --url "https://example.com"
mcp__playwright_screenshot --selector "body" --output "page.png"

# Screenshot specific element
mcp__playwright_screenshot --selector "#dashboard" --output "dashboard.png"

Element Interaction

# Click an element
mcp__playwright_click --selector "#submit-button"

# Fill form fields
mcp__playwright_fill --selector "input[name='email']" --value "[email protected]"
mcp__playwright_fill --selector "input[name='password']" --value "testpass123"

# Press keyboard keys
mcp__playwright_press --selector "input[name='search']" --key "Enter"

Content & Inspection

# Get page content
mcp__playwright_content --selector "body"

# Get element text
mcp__playwright_text_content --selector ".error-message"

# Get element attributes
mcp__playwright_get_attribute --selector "a.link" --attribute "href"

# Evaluate JavaScript
mcp__playwright_evaluate --script "document.querySelector('.price').innerText"

Viewport & Responsive Testing

# Set viewport for mobile testing
mcp__playwright_set_viewport --width 375 --height 667  # iPhone SE

# Set viewport for tablet
mcp__playwright_set_viewport --width 768 --height 1024  # iPad

# Set viewport for desktop
mcp__playwright_set_viewport --width 1920 --height 1080  # Full HD

COMMON WORKFLOWS

Workflow 1: Test Login Flow

# 1. Navigate to login page
mcp__playwright_navigate --url "https://app.example.com/login"

# 2. Take initial screenshot
mcp__playwright_screenshot --selector "body" --output "login-page.png"

# 3. Fill credentials
mcp__playwright_fill --selector "input[name='email']" --value "[email protected]"
mcp__playwright_fill --selector "input[name='password']" --value "password123"

# 4. Click login button
mcp__playwright_click --selector "button[type='submit']"

# 5. Wait and verify redirect (check URL or dashboard element)
mcp__playwright_screenshot --selector ".dashboard" --output "logged-in.png"

# 6. Report success
echo "✅ Login flow completed successfully"

Workflow 2: Debug CSS Issue

# 1. Navigate to page with issue
mcp__playwright_navigate --url "https://app.example.com/profile"

# 2. Capture desktop view
mcp__playwright_screenshot --selector ".profile-card" --output "desktop-view.png"

# 3. Switch to mobile viewport
mcp__playwright_set_viewport --width 375 --height 667

# 4. Capture mobile view
mcp__playwright_screenshot --selector ".profile-card" --output "mobile-view.png"

# 5. Inspect element styles
mcp__playwright_evaluate --script "getComputedStyle(document.querySelector('.profile-card')).display"

# 6. Report findings
echo "📊 Desktop shows correctly, mobile has display: none issue"

Workflow 3: Test Form Submission

# 1. Navigate to form
mcp__playwright_navigate --url "https://app.example.com/contact"

# 2. Fill all fields
mcp__playwright_fill --selector "#name" --value "Test User"
mcp__playwright_fill --selector "#email" --value "[email protected]"
mcp__playwright_fill --selector "#message" --value "This is a test message"

# 3. Submit form
mcp__playwright_click --selector "button.submit"

# 4. Check for success message
mcp__playwright_text_content --selector ".success-message"

# 5. Capture confirmation
mcp__playwright_screenshot --selector "body" --output "form-success.png"

Workflow 4: Extract Data from Page

# 1. Navigate to page
mcp__playwright_navigate --url "https://explorer.arkd.com/vtxos"

# 2. Get all vtxo IDs
mcp__playwright_evaluate --script "Array.from(document.querySelectorAll('.vtxo-id')).map(el => el.textContent)"

# 3. Get table data
mcp__playwright_content --selector "table.vtxos"

# 4. Export to file or process in code

BEST PRACTICES

1. Always Start with Navigation

# Good: Explicit navigation
mcp__playwright_navigate --url "https://app.example.com/page"
mcp__playwright_click --selector "#button"

# Bad: Assuming page is already loaded
mcp__playwright_click --selector "#button"  # May fail if page not loaded

2. Use Specific Selectors

# Good: Specific, unique selector
mcp__playwright_click --selector "#submit-form-button"
mcp__playwright_click --selector "button[data-testid='login']"

# Bad: Generic selector that may match multiple elements
mcp__playwright_click --selector "button"  # Which button?

3. Capture Screenshots for Evidence

# Always capture before and after states for debugging
mcp__playwright_screenshot --selector "body" --output "before-action.png"
mcp__playwright_click --selector "#delete-button"
mcp__playwright_screenshot --selector "body" --output "after-action.png"

4. Test Responsive Behavior

# Test key breakpoints
viewports=(
  "375x667"   # Mobile
  "768x1024"  # Tablet
  "1920x1080" # Desktop
)

for viewport in "${viewports[@]}"; do
  width=${viewport%x*}
  height=${viewport#*x}
  mcp__playwright_set_viewport --width $width --height $height
  mcp__playwright_screenshot --selector "body" --output "view-${viewport}.png"
done

5. Handle Async Operations

# Good: Wait for content to load after interaction
mcp__playwright_click --selector "#load-data-button"
sleep 2  # Give time for data to load
mcp__playwright_screenshot --selector ".data-table" --output "loaded-data.png"

# Better: Check for element visibility/content before proceeding
mcp__playwright_click --selector "#load-data-button"
mcp__playwright_wait_for_selector --selector ".data-table"  # If this tool exists

USE CASES BY CONTEXT

For ark-developer (Frontend Development)

• Validate new UI components render correctly
• Test form validation and error states
• Debug CSS issues across viewports
• Verify button clicks and navigation work
• Capture screenshots for documentation

For ark-tester (QA/Testing)

• Execute end-to-end user workflow tests
• Verify critical user paths (login, checkout, etc.)
• Test responsive design across devices
• Validate accessibility features
• Create visual regression baselines

LIMITATIONS

• No actual browser required: Playwright MCP runs headless browsers in the background
• JavaScript required: Sites with heavy JavaScript may need wait times
• No network inspection: Cannot intercept or modify network requests (use DevTools for that)
• Single page at a time: Cannot test multiple tabs/windows simultaneously in basic usage

TROUBLESHOOTING

Issue: Element not found

# Solution: Verify selector with content inspection first
mcp__playwright_content --selector "body"  # See full page HTML
# Then find correct selector in the output

Issue: Click has no effect

# Solution: Ensure element is visible and not covered
mcp__playwright_screenshot --selector "body" --output "before-click.png"
# Check if element is visible in screenshot, adjust selector if needed

Issue: Viewport not applying

# Solution: Set viewport BEFORE navigation
mcp__playwright_set_viewport --width 375 --height 667
mcp__playwright_navigate --url "https://app.example.com"

INTEGRATION WITH ARKADIAN WORKFLOW

When the ark-developer or ark-tester agents receive tasks involving web UIs:

1. Load this skill: Use the browser-testing skill
2. Identify test scenario: Login? Form? Visual bug?
3. Execute workflow: Follow patterns above
4. Capture evidence: Screenshots, extracted data
5. Report results: Success/failure with visual proof

EXAMPLES

Example 1: Test arkd Admin Dashboard

# Test dashboard loads and displays data
mcp__playwright_navigate --url "http://localhost:8080/admin"
mcp__playwright_screenshot --selector "body" --output "dashboard.png"
mcp__playwright_text_content --selector ".vtxo-count"
echo "Dashboard shows 42 VTXOs"

Example 2: Debug Mobile Menu

# Reproduce mobile menu bug
mcp__playwright_set_viewport --width 375 --height 667
mcp__playwright_navigate --url "http://localhost:8080"
mcp__playwright_click --selector ".hamburger-menu"
mcp__playwright_screenshot --selector "body" --output "mobile-menu-open.png"
echo "Bug confirmed: Menu overlaps content"

Example 3: Validate Form Validation

# Test email validation
mcp__playwright_navigate --url "http://localhost:8080/signup"
mcp__playwright_fill --selector "#email" --value "invalid-email"
mcp__playwright_click --selector "#submit"
mcp__playwright_screenshot --selector ".error" --output "validation-error.png"
mcp__playwright_text_content --selector ".error"
echo "✅ Email validation working: 'Please enter a valid email'"

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Remember: This skill gives you "eyes" on the browser. Use it whenever you need to see what users see, test what users do, or debug what users experience.