<p>Artificial intelligence (AI) is reshaping platform e-commerce. We build a game-theoretic model that accounts for consumer acceptance of return policies and the subscription price of AI tools, and use it to investigate an e-commerce platform’s AI adoption decision and a retailer’s choice between a money-back guarantee and no-return policy. This model highlights how AI helps reduce product mismatch and explores its role in optimizing the operational strategies of both the platform and the retailer. It also reveals their strategic interactions under decentralized decision-making, as well as the win–win conditions that encourage effective collaboration. Our results indicate that whether the platform benefits from increased consumer acceptance of the no-return policy depends on its AI adoption strategy. We also find that high AI effectiveness can mitigate the disadvantage of the money-back guarantee policy for the retailer under high return processing costs. Moreover, under different return policies, when AI effectiveness and its subscription fee meet certain conditions, the platform’s adoption of AI can not only increase its own profit but also achieve a win–win outcome with the retailer. Finally, we extend the research by introducing heterogeneous consumers and a bargaining game, and we validate the robustness of our findings through numerical analysis.</p>