The document discusses a framework for automatically testing agent-based systems using fault models. It proposes defining fault models that specify assumptions about when faults are likely to occur in the system under test. This allows an automated testing process to generate test cases, execute them, and identify any failures as existing faults. The framework extracts information from design documents to test individual units like plans without understanding their internal logic. It aims to provide comprehensive test coverage while reducing costs compared to manual testing. Defining fault models is meant to make the testing process more effective at revealing faults compared to existing techniques.