Urban design in hot–arid cities has often depended on implicit intuition rather than transparent, testable rules. This study develops a parametric framework that translates conceptual design principles into an algorithmic flowchart, making the design of a city’s “Main structure” explicit and reproducible. Through content analysis of structuralist, typological, and collective-form theories, we identified key parameters—including functional scale, durability, accessibility, connectivity, and visual legibility—and adapted them to climate-specific conditions. The results showed that connectivity, scale, and orientation thresholds were most decisive in shaping resilient urban routes, centers, and icons in the linear cities in the hot arid areas. By embedding these parameters in a stepwise, code-free algorithm, the method allows designers to evaluate alternatives systematically rather than relying on intuition. The contribution lies in operationalizing theoretical concepts into a portable design tool for hot–arid contexts, advancing both the scientific understanding of climate-adapted urban structure and the practical capacity to integrate parametric methods into early-stage planning.