A synthetic Crescent Tower facade sends its hottest reflected sunlight straight to the pool deck: 2.07× peak concentration, about 106 °C, and 6.0 hours a day at the focal area. Architectural renders can make a concave-glass concept feel resolved while its physical risk remains invisible. Generative tools produce pixels, not load paths. We built Caustic to put that check inside design iteration. It traces a defined 15-position summer-solstice sweep, then applies fixed thresholds: 1.45× concentration, 80 °C focal surface temperature, and 30 minutes of focal dwell. The FLAGGED verdict comes from deterministic ray tracing and a fixed policy gate. The Screening and Critic Agents explain the protocol and check it against the computed record. This is pre-screening only, not a stamped analysis. The goal is to surface the risk while geometry can still move, then hand off to full optical simulation and licensed review. For architecture and facade-engineering teams, where would a visible solar-path check change an early concept discussion? #FacadeEngineering #ComputationalDesign #BuildingPerformance #SolarAnalysis #ArchitectureTechnology