agent-browser - Claude MCP Skill

# Agent Browser Skill

Fast browser automation using accessibility tree snapshots with refs for deterministic element selection.

## Why Use This Over Built-in Browser Tool

**Use agent-browser when:**
- Automating multi-step workflows
- Need deterministic element selection
- Performance is critical
- Working with complex SPAs
- Need session isolation

**Use built-in browser tool when:**
- Need screenshots/PDFs for analysis
- Visual inspection required
- Browser extension integration needed

## Core Workflow

```bash
# 1. Navigate and snapshot
agent-browser open https://example.com
agent-browser snapshot -i --json

# 2. Parse refs from JSON, then interact
agent-browser click @e2
agent-browser fill @e3 "text"

# 3. Re-snapshot after page changes
agent-browser snapshot -i --json
```

## Key Commands

### Navigation
```bash
agent-browser open <url>
agent-browser back | forward | reload | close
```

### Snapshot (Always use -i --json)
```bash
agent-browser snapshot -i --json          # Interactive elements, JSON output
agent-browser snapshot -i -c -d 5 --json  # + compact, depth limit
agent-browser snapshot -s "#main" -i      # Scope to selector
```

### Interactions (Ref-based)
```bash
agent-browser click @e2
agent-browser fill @e3 "text"
agent-browser type @e3 "text"
agent-browser hover @e4
agent-browser check @e5 | uncheck @e5
agent-browser select @e6 "value"
agent-browser press "Enter"
agent-browser scroll down 500
agent-browser drag @e7 @e8
```

### Get Information
```bash
agent-browser get text @e1 --json
agent-browser get html @e2 --json
agent-browser get value @e3 --json
agent-browser get attr @e4 "href" --json
agent-browser get title --json
agent-browser get url --json
agent-browser get count ".item" --json
```

### Check State
```bash
agent-browser is visible @e2 --json
agent-browser is enabled @e3 --json
agent-browser is checked @e4 --json
```

### Wait
```bash
agent-browser wait @e2                    # Wait for element
agent-browser wait 1000                   # Wait ms
agent-browser wait --text "Welcome"       # Wait for text
agent-browser wait --url "**/dashboard"   # Wait for URL
agent-browser wait --load networkidle     # Wait for network
agent-browser wait --fn "window.ready === true"
```

### Sessions (Isolated Browsers)
```bash
agent-browser --session admin open site.com
agent-browser --session user open site.com
agent-browser session list
# Or via env: AGENT_BROWSER_SESSION=admin agent-browser ...
```

### State Persistence
```bash
agent-browser state save auth.json        # Save cookies/storage
agent-browser state load auth.json        # Load (skip login)
```

### Screenshots & PDFs
```bash
agent-browser screenshot page.png
agent-browser screenshot --full page.png
agent-browser pdf page.pdf
```

### Network Control
```bash
agent-browser network route "**/ads/*" --abort           # Block
agent-browser network route "**/api/*" --body '{"x":1}'  # Mock
agent-browser network requests --filter api              # View
```

### Cookies & Storage
```bash
agent-browser cookies                     # Get all
agent-browser cookies set name value
agent-browser storage local key           # Get localStorage
agent-browser storage local set key val
```

### Tabs & Frames
```bash
agent-browser tab new https://example.com
agent-browser tab 2                       # Switch to tab
agent-browser frame @e5                   # Switch to iframe
agent-browser frame main                  # Back to main
```

## Snapshot Output Format

```json
{
  "success": true,
  "data": {
    "snapshot": "...",
    "refs": {
      "e1": {"role": "heading", "name": "Example Domain"},
      "e2": {"role": "button", "name": "Submit"},
      "e3": {"role": "textbox", "name": "Email"}
    }
  }
}
```

## Best Practices

1. **Always use `-i` flag** - Focus on interactive elements
2. **Always use `--json`** - Easier to parse
3. **Wait for stability** - `agent-browser wait --load networkidle`
4. **Save auth state** - Skip login flows with `state save/load`
5. **Use sessions** - Isolate different browser contexts
6. **Use `--headed` for debugging** - See what's happening

## Example: Search and Extract

```bash
agent-browser open https://www.google.com
agent-browser snapshot -i --json
# AI identifies search box @e1
agent-browser fill @e1 "AI agents"
agent-browser press Enter
agent-browser wait --load networkidle
agent-browser snapshot -i --json
# AI identifies result refs
agent-browser get text @e3 --json
agent-browser get attr @e4 "href" --json
```

## Example: Multi-Session Testing

```bash
# Admin session
agent-browser --session admin open app.com
agent-browser --session admin state load admin-auth.json
agent-browser --session admin snapshot -i --json

# User session (simultaneous)
agent-browser --session user open app.com
agent-browser --session user state load user-auth.json
agent-browser --session user snapshot -i --json
```

## Installation

```bash
npm install -g agent-browser
agent-browser install                     # Download Chromium
agent-browser install --with-deps         # Linux: + system deps
```

## Credits

Skill created by Yossi Elkrief ([@MaTriXy](https://github.com/MaTriXy))

agent-browser CLI by [Vercel Labs](https://github.com/vercel-labs/agent-browser)