Declare the no-AI zone before the task

Most "AI misconduct" happens in the gap where no rule was stated and students guessed. Close the gap: for every significant task, say explicitly which of three modes applies. Open (AI allowed, disclosed), assisted (AI for specific stages only), or closed (none, and here's why). UNESCO's global guidance on generative AI in education urges exactly this kind of explicit, institutional clarity about appropriate use, rather than leaving each student to guess (Miao & Holmes, 2023).

In practice

• Announce the mode when you set the task, in writing, every time. The "why" matters most for closed tasks: "This one's practice for your brain, not production."
• Keep closed tasks structurally closed where you can (in class, on paper, spoken) rather than relying on trust plus detection.
• Be consistent across the department if possible. Students live in six different rule-sets a day, and every ambiguity gets resolved in favour of the loosest one.