CLI MCP Configuration Guide

This guide explains how to configure Codex CLI and Claude Code to connect to the Chrome MCP Server.

Overview

The Chrome MCP Server exposes its MCP interface at http://127.0.0.1:12306/mcp (default port). Both Codex CLI and Claude Code can connect to this endpoint to use Chrome browser control tools.

Codex CLI Configuration

Option 1: HTTP MCP Server (Recommended)

Add the following to your ~/.codex/config.json:

{
  "mcpServers": {
    "chrome-mcp": {
      "url": "http://127.0.0.1:12306/mcp"
    }
  }
}

Option 2: Via Environment Variable

Set the MCP URL via environment variable before running codex:

export MCP_HTTP_PORT=12306

Claude Code Configuration

Option 1: HTTP MCP Server

Add the following to your ~/.claude/claude_desktop_config.json:

{
  "mcpServers": {
    "chrome-mcp": {
      "url": "http://127.0.0.1:12306/mcp"
    }
  }
}

Option 2: Stdio Server (Alternative)

If you prefer stdio-based MCP communication:

{
  "mcpServers": {
    "chrome-mcp": {
      "command": "node",
      "args": ["/path/to/mcp-chrome/dist/mcp/mcp-server-stdio.js"]
    }
  }
}

Verifying Connection

After configuration, the CLI tools should be able to see and use Chrome MCP tools such as:

• chrome_get_windows_and_tabs - Get browser window and tab information
• chrome_navigate - Navigate to a URL
• chrome_click_element - Click on page elements
• chrome_get_page_content - Get page content
• And more...

Troubleshooting

Connection Refused

If you get "connection refused" errors:

1. Ensure the Chrome extension is installed and the native server is running
2. Check that the port matches (default: 12306)
3. Verify no firewall is blocking localhost connections
4. Run mcp-chrome-bridge doctor to diagnose issues

Tools Not Appearing

If MCP tools don't appear in the CLI:

1. Restart the CLI tool after configuration changes
2. Check the configuration file syntax (valid JSON)
3. Ensure the MCP server URL is accessible

Port Conflicts

If port 12306 is already in use:

1. Set a custom port in the extension settings
2. Update the CLI configuration to match the new port
3. Run mcp-chrome-bridge update-port <new-port> to update the stdio config

Environment Variables

Variable	Description	Default
MCP_HTTP_PORT	HTTP port for MCP server	12306
MCP_ALLOWED_WORKSPACE_BASE	Additional allowed workspace directory	(none)
CHROME_MCP_NODE_PATH	Override Node.js executable path	(auto)