AGENTS.md
A “README for agents”: a plain Markdown file with the context and instructions a coding agent needs to work on your project.
What it is
A predictable place for build/test commands, code style, project overview and security notes. Just standard Markdown, no required headings. Nested AGENTS.md files are allowed; the closest one to the edited file wins. agents.md reports use in 60,000+ open-source projects.
Stewardship
Originally developed collaboratively by OpenAI Codex, Amp, Google Jules, Cursor and Factory. Contributed by OpenAI to the Agentic AI Foundation (AAIF), a Linux Foundation directed fund formed 2025-12-09 with MCP (Anthropic) and goose (Block); platinum members include Anthropic, Block, OpenAI, AWS, Google, Microsoft, Bloomberg, Cloudflare. agents.md now says it is “stewarded by the Agentic AI Foundation under the Linux Foundation”. (Confirms the audit’s Appendix A claim.)
Who reads it (per agents.md)
VS Code, Zed, Cursor, Windsurf/Devin, GitHub Copilot, Devin, Gemini CLI (now superseded by Antigravity CLI; support there not checked), Junie, Aider, goose, opencode, RooCode (shut down), Kilo Code; also codex, amp. Claude Code reads it too (docs), see below. The list is the site’s own; per-tool behaviour varies.
Relation to CLAUDE.md
Claude Code’s native file is CLAUDE.md. Since v2.1.277 it reads AGENTS.md directly only when no CLAUDE.md/CLAUDE.local.md exists in or above the working directory; with both, only CLAUDE.md is read unless /config > Project instructions is set to claude-md-and-agents-md. The portable pattern: keep shared rules in AGENTS.md and make CLAUDE.md contain @AGENTS.md plus Claude-specific notes (a symlink works but breaks on Windows). Cursor has .cursor/rules (cursor-rules); Claude Code /init migrates those and others.
Related
- claude-marketplace-setup-guide - includes a section on AGENTS.md alongside agents.toml and SKILL.md
Sources
- https://agents.md (2026-09-30)
- https://www.linuxfoundation.org/press/linux-foundation-announces-the-formation-of-the-agentic-ai-foundation (2026-09-30)
- https://code.claude.com/docs/en/memory (2026-09-30)