MCP Guardian

mcp-guardian.org

Overview

MCP Guardian manages your LLM assistant’s access to MCP servers, handing you realtime control of your LLM’s activity.

📜 Message Logging - See traces for all of an LLM’s MCP server activity

💂 Message Approvals - Approve and deny individual tool call messages in real time

🤖 Automated Message Scans - Realtime automated checks for safety, privacy, etc (Coming Soon)

MCP Guardian also makes it a breeze to manage multiple MCP server configurations. Quickly switch between server collections without having to manually manage configuration files for your MCP host applications.

Development

This project uses nix to manage a development environment that can be used on Linux and macOS.

Quick Start - Linux / macOS

1. Install nix

2. Enable nix flakes

sudo sh -c 'echo "experimental-features = nix-command flakes" >> /etc/nix/nix.conf'

3. Enter dev shell

nix develop

4. Build project

just build-release

5. mcp-guardian and mcp-guardian-proxy are now in _build/bin/ which is in PATH of the dev shell.

Quick Start - Windows

1. Install git with symlink support (otherwise you will need to restore ./mcp-guardian/bindings before building).

2. Install rustup.

3. Install nodejs.

4. Install yarn.

npm install --global yarn

5. Install .dll dependencies. The easiest way to do this is to install Visual Studio and install the C++ development packages.

6. Install just

cargo install just

7. Enter repo root with git-bash (otherwise just won’t work and you’ll need to call cargo directly)

8. Build project

just build-release

Justfile

Available recipes:
    build
    build-release
    clean
    do DIR +RECIPE
    do-all +RECIPE
    fmt
    fmt-check
    lint
    readme-check
    readme-update
    test