3 files for Claude Code, Codex and OpenCode: before-and-after, before-and-after AGENTS.md, before-and-after CLAUDE.md — 450 tokens loaded in every session.
AGENTS.md A 447 tok CLAUDE.md A 3 tok .claude/settings.json A — These files are vercel-labs/before-and-after'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.