agent-browser

agent-browser: Browser Automation for Research

Vercel's headless browser CLI for AI agents. Uses ref-based element selection (@e1, @e2) from accessibility snapshots.

When to use this instead of WebSearch/WebFetch:

• WebFetch returns blocked/empty content (anti-scraping)
• You need to scroll through paginated results (Reddit, forums)
• You need visible engagement data (likes, comments, shares)
• You need to interact with a page (expand threads, load more)
• You need a screenshot for visual analysis

Setup Check

command -v agent-browser >/dev/null 2>&1 && echo "Installed" || echo "NOT INSTALLED - run: npm install -g agent-browser && agent-browser install"

Install if needed

npm install -g agent-browser
agent-browser install  # Downloads Chromium

Core Workflow

1. Navigate to URL
2. Snapshot to get interactive elements with refs
3. Interact using refs (@e1, @e2, etc.)
4. Re-snapshot after navigation or DOM changes

agent-browser open https://example.com
agent-browser snapshot -i --json
agent-browser click @e1
agent-browser snapshot -i

Key Commands

Navigation

agent-browser open <url>       # Navigate to URL
agent-browser back             # Go back
agent-browser forward          # Go forward
agent-browser reload           # Reload page
agent-browser close            # Close browser

Snapshots

agent-browser snapshot              # Full accessibility tree
agent-browser snapshot -i           # Interactive elements only (recommended)
agent-browser snapshot -i --json    # JSON output for parsing
agent-browser snapshot -c           # Compact (remove empty elements)

Interactions

agent-browser click @e1            # Click element
agent-browser fill @e1 "text"      # Clear and fill input
agent-browser type @e1 "text"      # Type without clearing
agent-browser press Enter          # Press key
agent-browser scroll down 500      # Scroll down
agent-browser scrollintoview @e1   # Scroll element into view
agent-browser select @e1 "option"  # Select dropdown option

Extract Information

agent-browser get text @e1          # Get element text
agent-browser get html @e1          # Get element HTML
agent-browser get value @e1         # Get input value
agent-browser get attr href @e1     # Get attribute
agent-browser get title             # Get page title
agent-browser get url               # Get current URL

Screenshots

agent-browser screenshot                      # Viewport screenshot
agent-browser screenshot --full               # Full page
agent-browser screenshot output.png           # Save to file
agent-browser screenshot --full output.png    # Full page to file

Wait

agent-browser wait @e1              # Wait for element
agent-browser wait 2000             # Wait milliseconds
agent-browser wait "text"           # Wait for text to appear

Research Patterns

Scrape a competitor blog

agent-browser open https://competitor.com/blog
agent-browser snapshot -i
agent-browser scroll down 1000
agent-browser snapshot -i          # Get more loaded content
agent-browser get text @e5         # Extract article title
agent-browser get attr href @e5    # Get article link

Read a Reddit/forum thread

agent-browser open https://reddit.com/r/privacy/comments/...
agent-browser snapshot -c
agent-browser scroll down 500
agent-browser snapshot -c          # Load more comments

Capture engagement metrics

agent-browser open https://example.com/article
agent-browser snapshot -i --json   # Look for share counts, comments
agent-browser screenshot metrics.png

Search within a site

agent-browser open https://competitor.com
agent-browser snapshot -i
agent-browser fill @e1 "search query"
agent-browser press Enter
agent-browser wait 2000
agent-browser snapshot -i          # Parse search results

Sessions (Parallel Research)

agent-browser --session site1 open https://competitor1.com/blog
agent-browser --session site2 open https://competitor2.com/blog
agent-browser session list

JSON Output

agent-browser snapshot -i --json

Returns:

{
  "success": true,
  "data": {
    "refs": {
      "e1": {"name": "Submit", "role": "button"},
      "e2": {"name": "Search", "role": "textbox"}
    }
  }
}