Claude Code reads AGENTS.md when CLAUDE.md is missing

Point Claude Code at a project with no CLAUDE.md and it now pulls its instructions from AGENTS.md, the file other coding agents already use, so a team running several agents on one repo can keep a single set of rules. CLAUDE.md still wins when both are present. Worth remembering what else that file can do: NVIDIA's AI Red Team showed a malicious Go dependency writing its own AGENTS.md mid-build to hijack Codex.