MCP Defender

Automatically protects MCP traffic in AI apps

🛡️ MCP Defender is a desktop app that protects AI apps like Cursor from a variety of attacks.

🚦 All MCP tool call requests and responses from AI apps are automatically proxied through MCP Defender.

🔎 The intercepted data is then checked against a set of signatures.

🔐 If anything harmful is detected, MCP Defender alerts you and asks if you want to allow or block the tool call.

Demos

MCP.Defender.Small.mp4

Quick Start

Download MCP Defender for Mac

Windows & Linux Coming Soon

Alternatively you can clone the git repo, and run it as follows:

# Install dependencies
npm install

# Start app
npm start

Which apps are automatically protected?

MCP Defender protects Cursor, Claude, Visual Studio Code and Windsurf.

Protection for more apps coming soon!

Contributing

We love contributions! Feel free to open issues for bugs or feature requests.

License

MCP Defender is licensed under the AGPL-3.0 license. For more details, see the LICENSE.