Claude Code now falls back to AGENTS.md
Thariq says the fallback is live and toggleable, and the replies moved straight on to skills.
Claude Code will read AGENTS.md when a folder has no CLAUDE.md, starting in version 2.1.277. Thariq announced it and said the behavior can be toggled in /config. Addy Osmani confirmed the same fallback rule, CLAUDE.md first, AGENTS.md if CLAUDE.md is not specified.
The practical effect is the end of a very common shim. Simon Willison, who has been maintaining one-line CLAUDE.md files whose entire contents point at the AGENTS.md sitting next to them, called it great. That is the whole win for most repos, one fewer pointer file per project, and one fewer thing to explain to a contributor who uses a different agent.
now I can stop dropping CLAUDEmd files which just contain "@AGENTSmd
The jab about extensions
Mario Zechner replied that all it took was adding a proper extension system to Claude Code, addressed directly at Thariq and flagged as a joke he could not resist. It lands because agent harnesses tend to hardcode this kind of behavior and then need real plumbing before they can make it configurable. Nothing in the announcement says how the fallback is implemented, so treat the extension system line as a jab rather than a description.
and all it took was to add a proper extension system to claude code
Skills are the next ask
Matt Pocock's response to the news was immediate and unsentimental, he asked for .agents/skills next. Theo pushed back on the premise. He said Anthropic's implementation of skills is far enough ahead of the industry that a shared, generic format would be a downgrade, and singled out the ability to execute Bash inline as the specific capability other tools lack. His word for generic skills was limiting.
For working engineers, the file name question and the skills question are not the same problem. A config file is just text, so converging on one name costs nothing and everybody gains. Skills carry execution semantics, and a lowest common denominator format has to drop whatever the strongest implementation can do. Nobody in this thread proposed a version of shared skills that keeps inline Bash.