Google's New AI Agent Works in Microsoft 365, Too. Here Is What That Changes.
The AI helper is coming loose from the office suite you bought. For a business that runs a bit of both, that is good news, and it brings a few new decisions.
By John Martines · October 11, 2026 · 6 min
Google's Gemini agent works in Gmail and Docs, and also inside Microsoft 365 and Slack, and it picks between Gemini and Claude models for each job. Here is what a small business with a mixed setup should do before it arrives.
Picture a small accounting office. The partners live in Outlook and Excel because their clients send Excel files. The front desk runs on Gmail and Google Calendar because that is what the office manager set up years ago. Shared folders are in Google Drive, and a few clients insist on Teams.
When owners like this ask which AI to buy, the honest answer has been "pick a side." Copilot works best in Microsoft's apps, Gemini in Google's. This week Google changed that answer.
On October 8, 2026, at its Gemini at Work event, Google Cloud's chief executive, Thomas Kurian, introduced the Gemini agent. Google calls it a single, universal agent for work.
An agent is an AI that does tasks, not just answers questions. Kurian's summary: "You give it objectives, not instructions." You hand it an outcome, like "pull together this week's open client requests and draft a status note for each," and it works through the steps.
Three things set it apart.
It goes where you already work. You call it up by typing @Gemini in Gmail, Docs, Sheets, Slides and Google Chat. Google says it also works inside Microsoft 365 and Slack, on the web, on phones, and on Windows and Mac computers.
It picks the model for each job. Behind the scenes it chooses which AI model to use. Today that includes Google's Gemini models and Anthropic's Claude models, with others promised later.
It can have helpers with their own identity. For bigger jobs, it can set up smaller "coworker" agents, each with its own identity and, Google says, its own email address, so you can see in the records which agent did what. Google also showed spending caps that pause an agent when it hits a limit.
It is in private preview now. Google says it will reach "select" Workspace Business and Enterprise plans soon. It has not said which plans or what it will cost.
How it got here:
- January 15, 2025: Google folded Gemini into its Workspace business plans instead of selling it as an add-on, and raised Business Standard from $12 to $14 per user per month.
- September 24, 2025: Microsoft added Anthropic's Claude models to Microsoft 365 Copilot, starting with its Researcher agent and Copilot Studio, its tool for building agents. Until then Copilot ran on OpenAI's models.
- October 9, 2025: Google launched Gemini Enterprise, at $30 per user per month, with a $21 Gemini Business plan for smaller teams, and said it would work inside Microsoft 365, Salesforce and SAP.
- October 2026: Google began replacing Gems, its saved custom assistants, with Skills in Workspace. (See [Google Is Swapping Gems for Skills](/articles/gemini-gems-to-skills).)
- October 8, 2026: Google introduced the Gemini agent.
You may not have to pick a side. Plenty of small businesses run a bit of everything: Microsoft for spreadsheets, Google for email, Slack or Teams for chat. Until now the AI helper only knew one of those worlds well. An agent that works across them fits how a mixed office actually runs.
The big vendors now share the same AI models. Microsoft's Copilot offers Claude. Google's agent uses Claude. The model inside matters less each year. What matters is what the agent can reach, what it is allowed to do, and what it costs.
One agent that reaches everything is a bigger set of keys. An assistant that can read your Gmail, your Excel files and your Slack messages can do more for you. It can also see more, and a mistake travels further. Before, your Google AI could not touch your Microsoft files. Soon, one connection may be all it takes.
You may already pay for some of this. Gemini is part of most Workspace business plans now, and many offices with Microsoft 365 have Copilot Chat included. Before buying a new AI product, check what your current plans cover. Our free [Already-Paid-For Finder](/tools/ai-finder) lists what comes with the common plans.
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