Global Chatagents.txt expires in two days. Nobody renewed the draft.
I've been building indexers for MCP, A2A, and agents.txt. After implementing all three: none of them solve discovery on their own. MCP has momentum but no directory. A2A has Google but barely any adoption. agents.txt was simplest and still couldn't get working group support.
Probably some discovery layer gets bolted on top, not replacing any of them. The standard nobody wrote yet.