OpenTabs: MCP Server with 100+ Plugins for Browser-Based AI Tool Access

OpenTabs is an MCP server paired with a Chrome extension that provides access to web applications through their internal APIs rather than public APIs. The system includes 100+ plugins exposing approximately 2,000 tools.

How It Works

The Chrome extension injects plugin adapters into matching browser tabs. The MCP server discovers these plugins at runtime and exposes their tools over Streamable HTTP. This approach allows AI agents to call functions like slack_send_message that hit the same endpoints the web app's frontend uses, running within the browser with the user's existing session.

Key Features

• No API keys or OAuth flows required
• No screenshots or DOM scraping
• Works with Claude Code, Cursor, Windsurf, or any MCP client
• Includes a plugin SDK for building new plugins

Setup and Usage

Install via npm: npm install -g @opentabs-dev/cli

Start the server: opentabs start

Plugin Development

The SDK includes a skill that improves with each plugin built—patterns, gotchas, and API discoveries get written back into it. According to the developer, you can point your AI at any website and it builds a plugin in minutes.

Current Status

The developer uses 5-6 plugins daily (Slack, GitHub, Discord, Todoist, Robinhood) and considers those solid. There are 100+ total plugins, but most need more testing. The developer requests help: if you try a plugin and something's broken, point your AI at it and open a PR.