utensils/mcp-nixos

uvx mcp-nixos  # run directly, no install (recommended)
pip install mcp-nixos
nix run github:utensils/mcp-nixos  or  nix profile install github:utensils/mcp-nixos
docker run --rm -i ghcr.io/utensils/mcp-nixos
NixOS/Home Manager/nix-darwin: environment.systemPackages = [ pkgs.mcp-nixos ]

Usage

• •nix(action="search", query="firefox", source="nixos", type="packages")
• •nix(action="info", query="firefox", source="nixos", type="package")
• •nix(action="cache", query="firefox", system="x86_64-linux") # binary cache status
• •nix_versions(package="python", limit=5) # historical versions with nixpkgs commit hashes
• •HTTP mode: MCP_NIXOS_TRANSPORT=http MCP_NIXOS_HOST=127.0.0.1 MCP_NIXOS_PORT=8000 mcp-nixos

Key features

• ✓Unified `nix` tool with actions search/info/stats/browse/channels/flake-inputs/cache across 11 sources (nixos, home-manager, darwin, flakes, flakehub, nixvim, nvf, noogle, wiki, nix-dev, nixhub)
• ✓nix_versions tool returns historical package versions with nixpkgs commit hashes, platform availability, and attribute paths
• ✓Binary cache status checks with download sizes; local flake inputs exploration from the Nix store (requires Nix)
• ✓Minimal footprint: ~1,030 tokens total for both tools (17 tools consolidated into 2)
• ✓No Nix/NixOS required to run — works on Windows, macOS, Linux via API queries

Best for

Nix/NixOS users and AI agents that need factual package names, config options, and version data instead of hallucinated ones.

Caveats

• ⚠flake-inputs action requires Nix installed locally; everything else queries public APIs
• ⚠Requires Python 3.11+ to run
• ⚠HTTP transport uses FastMCP (MCP endpoint defaults to /mcp)