@different-ai/opencode-browser

OpenCode Browser

Browser automation plugin for OpenCode.

Control your real Chrome browser with existing logins, cookies, and bookmarks. No DevTools Protocol, no security prompts.

Why?

Chrome 136+ blocks --remote-debugging-port on your default profile for security reasons. DevTools-based automation (like Playwright) triggers a security prompt every time.

OpenCode Browser uses a simple WebSocket connection between an OpenCode plugin and a Chrome extension. Your automation works with your existing browser session - no prompts, no separate profiles.

Installation

npx @different-ai/opencode-browser install

The installer will:

• Copy the extension to ~/.opencode-browser/extension/
• Guide you to load the extension in Chrome
• Update your opencode.json to use the plugin

Configuration

Add to your opencode.json:

{
  "plugin": ["@different-ai/opencode-browser"]
}

Then load the extension in Chrome:

• Go to chrome://extensions
• Enable "Developer mode"
• Click "Load unpacked" and select ~/.opencode-browser/extension/

Available Tools

Tool	Description
browser_status	Check if browser is available or locked
browser_kill_session	Take over from another OpenCode session
browser_navigate	Navigate to a URL
browser_click	Click an element by CSS selector
browser_type	Type text into an input field
browser_screenshot	Capture the visible page
browser_snapshot	Get accessibility tree with selectors
browser_get_tabs	List all open tabs
browser_scroll	Scroll page or element into view
browser_wait	Wait for a duration
browser_execute	Run JavaScript in page context

Multi-Session Support

Only one OpenCode session can use the browser at a time. This prevents conflicts when you have multiple terminals open.

• browser_status - Check who has the lock
• browser_kill_session - Kill the other session and take over

In your prompts, you can say:

• "If browser is locked, kill the session and proceed"
• "If browser is locked, skip this task"

Architecture

OpenCode Plugin ◄──WebSocket:19222──► Chrome Extension
       │                                    │
       └── Lock file                        └── chrome.tabs, chrome.scripting

Two components:

• OpenCode plugin (runs WebSocket server, defines tools)
• Chrome extension (connects to plugin, executes commands)

No daemon. No MCP server. No native messaging host.

Upgrading from v1.x

v2.0 is a complete rewrite with a simpler architecture:

• Run npx @different-ai/opencode-browser install (cleans up old daemon automatically)
• Replace MCP config with plugin config in opencode.json:

- "mcp": {
-   "browser": {
-     "type": "local",
-     "command": ["npx", "@different-ai/opencode-browser", "start"],
-     "enabled": true
-   }
- }
+ "plugin": ["@different-ai/opencode-browser"]

• Restart OpenCode

Troubleshooting

"Chrome extension not connected"

• Make sure Chrome is running
• Check that the extension is loaded and enabled
• Click the extension icon to see connection status

"Browser locked by another session"

• Use browser_kill_session to take over
• Or close the other OpenCode session

"Failed to start WebSocket server"

• Port 19222 may be in use
• Check if another OpenCode session is running

Uninstall

npx @different-ai/opencode-browser uninstall

Then remove the extension from Chrome and delete ~/.opencode-browser/ if desired.

Platform Support

• macOS ✓
• Linux ✓
• Windows (not yet supported)

License

MIT

Credits

Inspired by Claude in Chrome by Anthropic.