6.4.1. How Cowork Carries Out Multi-Step Work

💡 First Principle: Cowork works like a project lead turning a request into a checklist. It splits your request into steps, picks the right tool for each step, and reports as it goes. Because you can see each step, you can catch a wrong turn early instead of discovering it in the final result.

Getting there: open Microsoft Copilot and select Cowork in the toggle next to Chat at the top. Cowork runs in the browser, the Microsoft Copilot desktop app (Windows and macOS) and the mobile app (iPhone and Android).

The typical flow:

1. Describe the task and optionally attach material. The home page suggests starters such as Catch me up, Organize my inbox, Organize my week, Prep for a meeting, Plan an event, Prepare for my 1:1 and Research a company. A brief can be very long: up to 250,000 characters.
2. Watch Cowork break the request into steps. You see a thinking indicator, skill messages (for example "Preparing to compose emails"), step-by-step tool updates (for example "Composing your email"), a streaming response and interactive cards.
3. Interrupt, steer or pause. Messages you send while Cowork is busy are queued and handled in order. If a message changes direction, Cowork adjusts.
4. Approve actions when asked. Before sensitive actions, Cowork shows an approval dialog (6.4.3).
5. Review the results in the side panel and the output folder.

Giving Cowork material to work with:

• Add work context: files, people, emails, Teams chats, channels and meetings
• Upload images and files, or attach cloud files and folders from OneDrive, SharePoint or Teams
• Drag and drop, or use voice input

When Cowork needs you, it asks a multiple-choice question. You can pick an option, type your own answer or skip, and the task shows Needs user input until you respond. If your connection drops, Cowork reconnects automatically and keeps its progress.

Model and effort. Cowork has its own model picker, which defaults to Auto, and a reasoning effort setting (Light, Medium as the default, High, Extra High, Max). Higher effort is slower and uses more credits. A badge shows which model produced each response. The list of available models changes often, so don't rely on specific model names.

⚠️ Exam Trap: Cowork can only work with files in OneDrive and SharePoint (plus what you upload or attach), not files sitting on your local device. And because Cowork is billed by usage (model responses, tool and skill calls, image generation, browser tasks), choosing Max effort for a routine inbox clean-up wastes credits without improving the result.

Reflection Question: Halfway through a Cowork task to prepare a project launch, you realize the launch date in your brief was wrong. What should you do, and why is that better than cancelling and starting over?