utensils/mcp-nixos

What it solves

It prevents AI models from hallucinating package names and configuration options when helping users with NixOS, Home Manager, and other Nix-based ecosystems. By providing a bridge to real-time, accurate data, it ensures the AI uses existing packages and correct syntax rather than guessing.

How it works

This is a Model Context Protocol (MCP) server that acts as a data provider for AI agents. It exposes two primary tools—nix and nix_versions—which query a wide array of external APIs and registries. It can be run via uvx, Docker, Nix, or as a remote HTTP server, and does not require Nix to be installed on the host machine to function (unless accessing local store paths).

Who it’s for

Developers and system administrators using NixOS, Home Manager, nix-darwin, or Neovim configurations (via Nixvim/NVF) who want their AI coding assistants to have precise knowledge of the Nix ecosystem.

Highlights

• Comprehensive Data Sources: Accesses 130K+ NixOS packages, 23K+ system options, and data from FlakeHub, Noogle, and the NixOS Wiki.
• Low Context Overhead: Consolidates 17 potential tools into just two, minimizing token usage in the AI's context window.
• Version History: Provides historical package versions and specific commit hashes for reproducible builds via NixHub.
• Flexible Deployment: Supports multiple runtimes including Python (uvx/pip), Docker, and native Nix installations.