Most coding agents (Codex, Cursor, Copilot, etc. have standardized on AGENTS.md as the shared instruction file. Only Claude uses CLAUDE.md, never AGENTS.md. If your repo only has an AGENTS.md, Claude Code silently ignores it.
Preferred fix: Import AGENTS.md into CLAUDE.md
Create a CLAUDE.md at the repo root that imports your AGENTS.md:
@AGENTS.md
Claude loads the imported file at session start, then appends anything you add below it. AGENTS.md stays canonical.
Alternative fix: Check in a symlink
You can also symlink AGENTS.md as CLAUDE.md:
ln -s AGENTS.md CLAUDE.md
Then commit that symlink to Git.
Posted by Henning Koch to makandra dev (2026-07-20 14:03)