# MCP Guardian

[mcp-guardian.org](https://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)

<p align="center">
    <img src="./docs/src/resources/splash-page.png" />
</p>

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](https://nixos.org/) to manage a development environment that can be used on Linux and macOS.

### Quick Start - Linux / macOS

1. [Install nix](https://nixos.org/download/)

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

3. Enter dev shell
```bash
nix develop
```

4. Build project
```bash
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](https://git-scm.com/downloads/win) with symlink support (otherwise you will need to restore `./mcp-guardian/bindings` before building).

2. [Install rustup](https://www.rust-lang.org/tools/install).

3. [Install nodejs](https://nodejs.org/en/download).

4. Install `yarn`.
```bash
npm install --global yarn
```

5. Install .dll dependencies. The easiest way to do this is to [install Visual Studio](https://visualstudio.microsoft.com/downloads/) and install the C++ development packages.

6. Install just
```bash
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
```bash
just build-release
```

### Justfile

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