Three categories. They are not about capability, they are about who carries the consequence. Copilot will attempt all three, confidently.
A budget, an invoice, two cost reports, a headcount that has to tie to payroll. A model returns a total that looks right and matches neither source. Use a formula, a query or a script, then use Copilot to explain the result to a human.
A hire, a go or no-go, a performance rating, a supplier you are about to drop. The draft is not the problem. The problem is that a fluent draft makes the decision feel already made. Write the call yourself, then ask Copilot what you missed.
Client personal data, anything under a data-residency commitment, anything covered by an NDA, pasted into a surface whose route you have not confirmed. Confirm the route first. Once it is in, it is in.
<aside> ⚠️ AI prepares, humans decide. Nothing on this page is an argument for using Copilot to authorise safety work. A permit to work, a lockout, a confined-space entry, a job safety analysis, an incident classification, an inspection sign-off: a person signs those, every time, and Copilot is not in that loop.
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If your industry has a version of that list, write it down and add it here before you hand this page to anybody else. There is a page for that: Copilot decision log, one row per decision. The row is finished when somebody's name is in it.
Part of Copilot on One Page, by Mathieu Kessler, independent practitioner: kesslernity.com. Checked against Microsoft's own documentation in August 2026. Free to use and print, personally or inside your business. Keep the source credit. Full terms: kesslernity.com/license.