AGENTS.md vs CLAUDE.md: Where Agent Context Actually Lives
AGENTS.md vs CLAUDE.md: Where Agent Context Actually Lives If you have opened three different repos this month and found three different context files (AGENTS.md in one, CLAUDE.md in another, both in a third, out of sync), you are not imagining the mess. AGENTS.md is now an open, vendor neutral standard that most major coding agents read, but CLAUDE.md has not gone away, and knowing which file wins where saves you from an agent quietly following stale instructions. What AGENTS.md actually is AGENTS.md started as a proposal from Sourcegraph's Amp team to fix a specific problem: every coding agent invented its own context file, so teams ended up maintaining CLAUDE.md, .cursorrules, .windsurfrules, and whatever else, all describing the same project. OpenAI and Google backed the standard, and it has since moved under the Linux Foundation's Agentic AI Foundation. Guides tracking adoption report 28+ supporting tools and more than 60,000 open source repos containing the file (secondary source, treat the exact counts as approximate, not audited). The pitch is simple: one Markdown file, one format, every agent reads the same source of truth instead of you hand syncing five files that drift within a week. Which tools actually read it This is the part that matters when you are deciding whether to migrate. Tools with native AGENTS.md support include: GitHub Copilot coding agent Cursor Amp Factory RooCode Zed Warp Notice what is not confirmed on that list. Reports that Claude Code reads AGENTS.md natively circulate in comparison guides, but I could not verify this against Anthropic's own changelog, so I am stating it qualitatively here rather than as fact: treat it as unconfirmed until you see it in Anthropic's own docs, and keep CLAUDE.md in place as your safety net if you rely on Claude Code specifically. AGENTS.md vs CLAUDE.md vs the well known directory Three layers get conflated constantly, and they solve different problems. Layer What it is Scope AGENTS.md Vendor neutral p