Understanding how cities respond to stress can inform possible planning, design, and management changes to advance health, safety, and welfare. This paper considers antifragility, which is a property of some systems to improve when exposed to volatility, as a means to understand dynamics of dense urban areas. It presents a computational framework to assess if urban systems are becoming fragile or antifragile by tracking changes in service capacities following disruption. The Political, Military, Economic, Social, Infrastructure, and Information (PMESII) categorization is adapted to reference capabilities and extended to pose and test hypotheses about system orders for urban areas.