Claude Code skill for spec-faithful implementation: spec-derived tests, mandatory boundary coverage, evidence-gated done reports. Every rule TDD-tested against real baseline failures on Opus/Sonnet/Haiku.
1 file for Claude Code and Codex: off-by-none CLAUDE.md — 389 tokens loaded in every session.
CLAUDE.md A 389 tok These files are NTCHz/off-by-none's own configuration — they tell Claude Code and Codex 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.