Microsoft announced Agent 365 last month, positioning it as the control plane for managing agents at enterprise scale. The pitch is elegant: extend your existing M365 infrastructure to agents. Use Entra for identity, Defender for security, Purview for compliance. No rebuilding required.
Except there's rebuilding required.
The platform is real, and the architectural thinking is solid. But "managing agents like users" glosses over what that actually means. You're not just flipping switches in your existing admin console. You're building governance infrastructure for entities that make decisions, access data, and take actions without human oversight.
Microsoft's own documentation lists the work: authentication models, conditional access policies, threat modeling, compliance frameworks, measurement systems. Their internal team admits they're "only at the beginning" of figuring out how to measure agent impact.
The control plane exists. The "just plug it in" part needs an asterisk.