Shows a black knight in light color mode and a white knight one in dark color mode.

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.

Windows & Linux Coming Soon

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

# Install dependencies
npm install

# Start app
npm start

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

Protection for more apps coming soon!

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

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