Browser Automation

Browser Automation Skill

This skill provides local browser automation capabilities using Python and Playwright. All browser automation is performed locally via CLI commands - no MCP servers required.

Prerequisites

Install Playwright Python library:

pip install playwright
playwright install chromium

Available Tools

All tools are implemented as subcommands in assets/skills/browser-automation/scripts/browser_tools.py. Run any command with --help to see detailed usage.

browser_navigate

Navigate to a URL and wait for the page to load.

Usage:

python assets/skills/browser-automation/scripts/browser_tools.py browser_navigate <url>

Example:

python assets/skills/browser-automation/scripts/browser_tools.py browser_navigate https://example.com

browser_click

Click an element on a page using a CSS selector or text match.

Usage:

python assets/skills/browser-automation/scripts/browser_tools.py browser_click <url> <selector> [--text TEXT]

Parameters:

• url: URL to navigate to
• selector: CSS selector for the element
• --text: (Optional) Text to match instead of using selector

Examples:

# Click by selector
python assets/skills/browser-automation/scripts/browser_tools.py browser_click https://example.com "#submit-button"

# Click by text
python assets/skills/browser-automation/scripts/browser_tools.py browser_click https://example.com "button" --text "Submit"

browser_type

Type text into an input field, with optional form submission.

Usage:

python assets/skills/browser-automation/scripts/browser_tools.py browser_type <url> <selector> <text> [--submit]

Parameters:

• url: URL to navigate to
• selector: CSS selector for the input field
• text: Text to type
• --submit: (Optional) Press Enter after typing

Examples:

# Type into field
python assets/skills/browser-automation/scripts/browser_tools.py browser_type https://example.com "#email" "user@example.com"

# Type and submit
python assets/skills/browser-automation/scripts/browser_tools.py browser_type https://example.com "#search" "query" --submit

browser_screenshot

Capture a screenshot of the current page.

Usage:

python assets/skills/browser-automation/scripts/browser_tools.py browser_screenshot <url> <path> [--full_page]

Parameters:

• url: URL to navigate to
• path: Output file path for the screenshot
• --full_page: (Optional) Capture the entire scrollable page

Examples:

# Viewport screenshot
python assets/skills/browser-automation/scripts/browser_tools.py browser_screenshot https://example.com /tmp/screenshot.png

# Full page screenshot
python assets/skills/browser-automation/scripts/browser_tools.py browser_screenshot https://example.com /tmp/full.png --full_page

browser_get_content

Extract text or HTML content from the page or a specific element.

Usage:

python assets/skills/browser-automation/scripts/browser_tools.py browser_get_content <url> [--selector SELECTOR] [--html]

Parameters:

• url: URL to navigate to
• --selector: (Optional) CSS selector, defaults to 'body'
• --html: (Optional) Return HTML instead of text

Examples:

# Get all page text
python assets/skills/browser-automation/scripts/browser_tools.py browser_get_content https://example.com

# Get specific element text
python assets/skills/browser-automation/scripts/browser_tools.py browser_get_content https://example.com --selector "#main-content"

# Get HTML
python assets/skills/browser-automation/scripts/browser_tools.py browser_get_content https://example.com --selector "article" --html

browser_hover

Hover over an element to trigger hover states or tooltips.

Usage:

python assets/skills/browser-automation/scripts/browser_tools.py browser_hover <url> <selector>

Parameters:

• url: URL to navigate to
• selector: CSS selector for the element

Example:

python assets/skills/browser-automation/scripts/browser_tools.py browser_hover https://example.com ".menu-item"

browser_evaluate

Execute custom JavaScript code in the browser context.

Usage:

python assets/skills/browser-automation/scripts/browser_tools.py browser_evaluate <url> <script>

Parameters:

• url: URL to navigate to
• script: JavaScript code to execute

Examples:

# Get page title
python assets/skills/browser-automation/scripts/browser_tools.py browser_evaluate https://example.com "document.title"

# Get element count
python assets/skills/browser-automation/scripts/browser_tools.py browser_evaluate https://example.com "document.querySelectorAll('button').length"

# Manipulate DOM
python assets/skills/browser-automation/scripts/browser_tools.py browser_evaluate https://example.com "document.body.style.backgroundColor = 'red'"

Best Practices

1. Always use full URLs: Include the protocol (http:// or https://)
2. Wait for content: The tool automatically waits for 'networkidle' state
3. Use robust selectors: Prefer ID selectors (#id) or specific CSS classes
4. Error handling: All commands exit with non-zero status on failure and print errors to stderr
5. Headless mode: All operations run in headless Chromium by default

Common Patterns

Form Automation

# Fill out a multi-field form
python assets/skills/browser-automation/scripts/browser_tools.py browser_type https://example.com "#name" "John Doe"
python assets/skills/browser-automation/scripts/browser_tools.py browser_type https://example.com "#email" "john@example.com"
python assets/skills/browser-automation/scripts/browser_tools.py browser_click https://example.com "#submit"

Visual Testing

# Note: Each command runs in a separate browser instance (stateless).
# The after screenshot won't show the toggled state from the click command.
# For stateful testing, combine actions in a custom Playwright script.

# Capture initial state
python assets/skills/browser-automation/scripts/browser_tools.py browser_screenshot https://example.com /tmp/before.png

# Compare different pages or states (each is independent)
python assets/skills/browser-automation/scripts/browser_tools.py browser_screenshot https://example.com/page1 /tmp/page1.png
python assets/skills/browser-automation/scripts/browser_tools.py browser_screenshot https://example.com/page2 /tmp/page2.png

Content Extraction

# Extract and process page content
python assets/skills/browser-automation/scripts/browser_tools.py browser_get_content https://example.com --selector "article" > article.txt

Architecture

• Stateless design: Each command launches a new browser instance
• No persistent sessions: Browser closes after each operation
• Local execution: All automation runs locally, no remote MCP servers
• Simple I/O: Results printed to stdout, errors to stderr

Troubleshooting

If you encounter issues:

1. Install Playwright browsers: Run playwright install chromium
2. Check Python version: Requires Python 3.8+
3. Verify URL accessibility: Ensure the target URL is reachable
4. Inspect selectors: Use browser DevTools to verify CSS selectors

Related Resources

• Examples: assets/skills/webapp-testing/examples/
• Playwright Documentation: https://playwright.dev/python/