Object-oriented design notations represent application domains in terms of interacting classes where each class provides well-defined services. During implementation of an object-oriented design, the focus lies on individual classes rather than on groups of interacting classes. But individual classes usually implement only small, cohesive parts of system tasks. Important parts of algorithms behind system tasks are hidden in changing object graphs. This can cause malicious problems during restructuring, testing and documentation of object-oriented programs, if there is no systematic approach to these activities.The article describes an architecture model, a tool and their application for rigorous analysis of hybrid, object-oriented programs at the abstraction level of object graphs and interactions. Analysis results are intended especially to support incremental development of object-oriented programs, dynamic documentation and dynamic testing. Object-oriented C++ programs serve as analysis objects