import { pageMetadata } from "@/lib/page-metadata"
export const metadata = pageMetadata("cdp-mode")
# CDP Mode
Connect to an existing browser via Chrome DevTools Protocol:
Default behavior in this fork: when `--cdp` is omitted, agent-browser requires an existing browser at `localhost:9333`. If CDP is unavailable, the command fails fast (no local-launch fallback).
Project policy:
- `--profile` / `AGENT_BROWSER_PROFILE` are forbidden
- `--channel` / `AGENT_BROWSER_CHANNEL` are forbidden
```bash
# Start Chrome with: google-chrome --remote-debugging-port=9222
# Connect once, then run commands without --cdp
agent-browser connect 9222
agent-browser snapshot
agent-browser tab
agent-browser close
# Or pass --cdp on each command
agent-browser --cdp 9222 snapshot
```
## Remote WebSocket URLs
Connect to remote browser services via WebSocket URL:
```bash
# Connect to remote browser service
agent-browser --cdp "wss://browser-service.com/cdp?token=..." snapshot
# Works with any CDP-compatible service
agent-browser --cdp "ws://localhost:9222/devtools/browser/abc123" open example.com
```
The `--cdp` flag accepts either:
- A port number (e.g., `9222`) for local connections via `http://localhost:{port}`
- A full WebSocket URL (e.g., `wss://...` or `ws://...`) for remote browser services
## Auto-Connect
Use `--auto-connect` to automatically discover and connect to a running Chrome instance without specifying a port:
```bash
# Auto-discover running Chrome with remote debugging
agent-browser --auto-connect open example.com
agent-browser --auto-connect snapshot
# Or via environment variable
AGENT_BROWSER_AUTO_CONNECT=1 agent-browser snapshot
```
Auto-connect discovers Chrome by:
1. Reading Chrome's `DevToolsActivePort` file from the default user data directory
2. Falling back to probing common debugging ports (9222, 9229, 9333)
This is useful when:
- Chrome 144+ has remote debugging enabled via `chrome://inspect/#remote-debugging` (which uses a dynamic port)
- You want a zero-configuration connection to your existing browser
- You don't want to track which port Chrome is using
## Color scheme
Playwright overrides the browser's color scheme to `light` by default when connecting via CDP. Use `--color-scheme` to set a persistent preference:
```bash
agent-browser --cdp 9222 --color-scheme dark open https://example.com
agent-browser --cdp 9222 snapshot # stays in dark mode
```
Or set it globally via config or environment variable:
```bash
AGENT_BROWSER_COLOR_SCHEME=dark agent-browser --cdp 9222 open https://example.com
```
## Stealth behavior
`--stealth` is enabled by default across connection modes, but capabilities depend on how you connect:
| Connection type | Stealth capabilities |
| Local launch | Chromium launch args + context init scripts |
| CDP / auto-connect | Context init scripts |
| Cloud providers | Context init scripts (Kernel may also apply provider-managed stealth) |
Use `--debug` to print the active connection type and applied stealth capabilities.
## Use cases
This enables control of:
- Electron apps
- Chrome/Chromium with remote debugging
- WebView2 applications
- Remote browser services (via WebSocket URL)
- Any browser exposing a CDP endpoint
## Global options
| Option | Description |
--session <name> | Use isolated session |
-p <provider> | Cloud browser provider (browserbase, browseruse, kernel) |
--headers <json> | HTTP headers scoped to origin |
--executable-path | Custom browser executable |
--args <args> | Browser launch args (comma-separated) |
--user-agent <ua> | Custom User-Agent string |
--proxy <url> | Proxy server URL |
--proxy-bypass <hosts> | Hosts to bypass proxy |
--json | JSON output for scripts |
--full, -f | Full page screenshot |
--name, -n | Locator name filter |
--exact | Exact text match |
--headed | Show browser window |
{"--cdp "} | CDP connection (port or WebSocket URL) |
--auto-connect | Auto-discover and connect to running Chrome |
--color-scheme <scheme> | Persistent color scheme (dark, light, no-preference) |
--debug | Debug output |
## Cloud providers
Use cloud browser infrastructure when local browsers aren't available:
```bash
# Browserbase
export BROWSERBASE_API_KEY="your-api-key"
export BROWSERBASE_PROJECT_ID="your-project-id"
agent-browser -p browserbase open https://example.com
# Browser Use
export BROWSER_USE_API_KEY="your-api-key"
agent-browser -p browseruse open https://example.com
# Kernel
export KERNEL_API_KEY="your-api-key"
agent-browser -p kernel open https://example.com
# Or via environment variable
export AGENT_BROWSER_PROVIDER=browserbase
agent-browser open https://example.com
```
The `-p` flag takes precedence over `AGENT_BROWSER_PROVIDER`.