Interchange formats are notoriously difficult to finish. That is, once one is developed, it is highly nontrivial to prove (or disprove) generality, and difficult at best to gain acceptance from all major players in the application domain. This paper addresses such a problem for hybrid systems, but not from the perspective of a tool interchange format, but rather that of tool availability in a toolbox. Through the paper we explain why we think this is a good approach for hybrid systems, and we also analyze the domain of hybrid systems to discern the semantic partitions that can be formed to yield a classification of tools based on their semantics. These discoveries give us the foundation upon which to build semantic capabilities, and to guarantee operational interaction between tools based on matched operational semantics.