Anthropic did all this and didn't even do the BARE MINIMUM of adding AGENTS.md support to Claude Code:

Donating the Model Context Protocol and establishing the Agentic AI Foundation

Anthropic is an AI safety and research company that's working to build reliable, interpretable, and steerable AI systems.

Codex and goose both support it (both are also Open Source) Why even have standards if you don't use them? It would be a 1-line change in Claude Code​ to change CLAUDE.md to AGENTS.md​. I would submit a PR, but it's closed source!