April 2026 was the month identity-for-agents stopped being a niche concern and started looking like an industry standard. OpenAI joined the FIDO Alliance Board on April 13. Two weeks later, on April 28, FIDO announced an Agentic Authentication Technical Working Group, co-chaired by members from CVS Health, Google, and OpenAI. Around the same time, an academic paper called AgentDID landed on arXiv ( 2604.25189 ) proposing W3C DIDs and verifiable credentials as the substrate for self-sovereign agent identity. If you squint, all three are doing the same thing. They're building a credible answer to who is this agent . Necessary work. Not enough. What April actually shipped AgentDID ties an agent's identity to three attribute dimensions (provenance, capabilities, compliance) anchored on-chain via DIDs and VCs. The challenge-response mechanism asks an agent to present evidence of current execution conditions at interaction time.…