Nadella Rebuilds Microsoft Around Agents, Splits Into Two Segments

Nadella's letter ties Microsoft's internal reorganization to a specific architectural bet. By separating what he calls the harness — context, memory and action space — from the model itself, Microsoft says it can route work to the "right model for the right job" across more than 11,000 models from OpenAI, Anthropic, Mistral, SpaceX and its own MAI family. The stated payoff is twofold: optimizing what he calls the "cost-to-outcome frontier," and business continuity, because interchangeable models reduce dependence on any single provider.

The customer-control argument follows from the same design. Nadella says customers should be able to "switch out a 'generalist' model without losing the 'company veteran' expertise accumulated in their learning system" — a way of making model choice a procurement decision rather than a lock-in. Copilot's move from synchronous chat assistants to asynchronous agents that complete long-running tasks, and its surpassing 30 million paid seats, are presented as evidence that this shift is already underway. Agent 365 extends the logic to management: agents handled the way companies handle people.