AI Agents for Students: Cheating or Learning Tool?

My son is in college, and he uses an AI agent to study. He doesn't have it write his essays. Instead, he feeds it his lecture notes, and it quizzes him on the material. It generates practice questions and explains concepts he doesn't get. His grades have improved dramatically. The school is still figuring out the policy, but to me, this is the same as a tutor. The line between 'tool' and 'cheating' is blurry, but if used right, these agents could be the greatest educational aid since the internet.