Nadella makes Agent Mode the default in Copilot and propels Office 365 into the agent era at Build 2026
Office 365 Copilot gains Agent Mode as the default state in the June rollout. Azure AI Foundry transforms into a control tower for orchestration at scale, and Windows Local AI redefines data sovereignty friction.
Satya Nadella took the stage at the Fort Mason Center in San Francisco on Tuesday morning (2nd) to open Microsoft Build 2026 with a product reorientation that changes the default use of Copilot across the business portfolio. "Agents are not a feature. They are the new operating system of work," stated the CEO of Microsoft. The embedded message in his statement is practical: Agent Mode will become the default state of Office 365 Copilot starting from the expected rollout at the end of June.
The change may seem minor in marketing terms but is enormous in behaviour. Until now, Copilot within Word, Excel, Teams, and Outlook responded to commands like a turn-based chatbot. In Agent Mode, the agent persists between sessions, maintains context across applications, executes multi-step actions without confirming each intermediate action, and triggers workflows from Power Automate when it recognises intent. The configuration for human approval remains with the user, but the initial state is to act, not ask.
Azure AI Foundry becomes the command centre
For the IT sector, the significant announcement is the repositioning of Azure AI Foundry as the enterprise control tower for the orchestration of agents at scale. The new Agent Orchestrator will enter preview in August and promises to distribute workload among thousands of agents, integrate with Azure Logic Apps for workflow triggers, and expose a unified dashboard for billing and governance. Scott Guthrie, Executive Vice President of Cloud + AI, accompanied Nadella on stage and detailed the component as the missing piece to "take agents out of the pilot phase and into governed production".
Microsoft has adoption data to support the urgency. The installed base of Copilot for Microsoft 365 already accounts for significant segments of the Fortune 500. The internal takeaway circulating among invited ISVs at Build is that the barrier today is not the purchase of Copilot, but the migration to the agent mode, which requires redesigning processes, defining owners for each agent, and instituting internal SLAs regarding what the agent can or cannot do without human approval.
Windows Local AI and the autonomous GitHub Copilot
The less expected piece came on the client front. Windows Local AI, embedded in version 24H2 of Windows 11, allows agents to run entirely on the device's silicon, using NPUs present in the Copilot+ PCs released by Qualcomm, Intel, and AMD in 2024 and 2025. Microsoft frames this change as compliance with data sovereignty requirements in jurisdictions such as the European Union, Germany, and Japan. With no data leaving the machine, part of the friction from the AI Act becomes moot.
On GitHub, Copilot has graduated from autocomplete to autonomous coding agent. The Autonomous mode, expected in July, enables the agent to open issues, write tests, execute the pipeline, and create pull requests under optional human review. The Windows Agent Framework and the Copilot Agent SDK, released together, provide external developers with the same primitives that Microsoft uses internally.
How the market views this outside the US
For consultancies implementing Microsoft in the enterprise, such as Accenture, Capgemini, Deloitte, and TCS, the effect is twofold. The demand for engagement in process redesign is increasing because every client needs to redesign workflows for Agent Mode. At the same time, the agent is replacing junior staff that these same partners sold by the hour. Accenture, which cut 11,000 positions in December 2025 under the justification of reskilling, will have to deliver trained benches in Microsoft agent orchestration within a few months. Capgemini, which bet on Generative Engineering as a revenue vector, gains a certified product to sell in the new context, with immediate upside over competitors that did not anticipate the shift.
In Japan, where the financial industry spent 2025 testing Microsoft 365 Copilot under strict data restrictions, Windows Local AI redefines what was previously unfeasible. MUFG, Mizuho, and Nomura had already been operating pilot projects. The new development may resolve the objection concerning data exit for the Financial Services Agency regulating the sector without necessitating the construction of a dedicated data centre. The adoption timeline is likely to accelerate in the second half of the year, and local integration partners (NRI, NEC, Fujitsu) emerge with a competitive advantage over integrators that have yet to certify squads in Agent Framework.
The big question that went unanswered in the keynote is about pricing. Will Agent Mode maintain the cost of $30 per user per month for Microsoft 365 Copilot, or will it open a separate tier based on agent usage intensity? Without that answer, the average CFO is likely to hold off on expansion until the third quarter, when Microsoft will close the invoice for the first complete month of the new mode. The fate of Microsoft's FY27 revenue guidance hinges on this decision.