Abstract: In response to the limitations of traditional methods in the field of architectural stair design, this study introduces an intelligent design framework based on the Grasshopper platform, along with the development of corresponding design tools. The tool employs parametric design techniques and visual programming methods, allowing users to input design parameters and automatically complete the precise calculation of stair dimensions, while simultaneously generating construction drawings and three-dimensional models. This process not only enhances design efficiency but also ensures the compliance and safety of the design scheme through an automated design review mechanism constructed with intelligent geometric algorithms. Practical engineering applications have shown that the tool has significant economic benefits and practical value in the design of parallel double-run stairs, effectively reducing the design cycle, lowering design costs, and improving the accuracy and reliability of the design scheme. The innovation of this study lies in applying advanced design technology to the traditional construction field, providing an efficient and accurate solution for architectural stair design, which has important engineering application value and prospects for promotion.