3 files for Claude Code, Codex and OpenCode: building-installers, nix-config AGENTS.md, nix-config CLAUDE.md — 1,285 tokens loaded in every session.
AGENTS.md B 153 tok CLAUDE.md B 1,132 tok .claude/skills/building-installers/SKILL.md D 40 tok These files are joshsymonds/nix-config's own configuration — they tell Claude Code, Codex and OpenCode how to work on this repository, so they are not mods to install elsewhere. Copy one as a starting point and replace the parts that are about this project.