What to Use When: Copilot for Office, Agent Mode, and Agents in Office

• Agent Mode introduces chat in Office that directly modifies files but doesn’t support all the apps’ features.
• Anthropic’s models and agents are interesting, but data is transferred outside of Azure and may trigger regulatory issues.
• Microsoft’s integration of M365 Copilot into Office has underwhelmed, and Agent Mode is its latest strategic direction.
• Having multiple options can confuse users and requires training.

New features for M365 Copilot for Excel, PowerPoint, and Word introduce overlapping capabilities to create and revise content using chat. The features are intended to increase productivity for employees, but personal productivity is hard to measure, and the AI output needs refinement. The features require an M365 Copilot license, and those from Anthropic involve its subprocessor agreement, which should be reviewed for compliance. Some features are in the Frontier preview program but are on track for general availability in Q1 2026.

This report covers the way that Copilot for Office, Agent Mode, and Office agents overlap and can work together. (“Copilot for Office” refers to M365 Copilot for Excel, PowerPoint, and Word.)