In today's software engineering environment, it is becoming increasingly commonplace for team members and stakeholders to be distributed in multiple locations and time zones. Under these circumstances, the coordination of software development activities becomes increasingly more complex. One solution uses mobile agent-based tools to support collaboratives software engineering tasks, such as requirements management. Despite the fact that development and validation of such tools would be facilitated by the use of modeling and simulation, very little work relating formal methods to agent-based system development has been performed. This paper therefore presents a hierarchical colored Petri Net (CPN) model as a formal framework for agent-based distributed software development, and demonstrates its usefulness by applying the framework to the development of a requirements management system.