Generative design, an AI-assisted technology for optimizing design through algorithmic processes, is propelling advancements across numerous fields. As the use of immersive environments such as Augmented Reality (AR) continues to rise, integrating generative design into such platforms presents a potent opportunity for innovation. However, a vital challenge that impedes this integration is the current absence of an efficient and user-friendly interface for designers to operate within these environments effectively. To bridge this gap, we introduce a novel UI system for generative design software in AR, which automates the process of generating the potential design constraints based on the users' inputs. This system allows users to construct a virtual environment, edit objects and constraints, and export the final data in CSV format. The interface enhances the user's design experience by enabling more intuitive interactions and providing immediate visual feedback. Deriving from participatory design principles, this research proposes a significant leap forward in the realms of generative design and immersive environments.