OO Design Principle Evaluator

When to Use

Use this skill when you are:

• Reviewing a class hierarchy — assessing whether inheritance is being used correctly or overused
• Deciding between inheritance and composition — need a principled recommendation for a specific design choice
• Diagnosing brittleness — a subclass is breaking when parent classes change, indicating broken encapsulation
• Designing for flexibility — want behavior that can change at runtime, which inheritance cannot provide
• Code reviewing OO designs — evaluating whether a design follows established reuse best practices

Preconditions: you have at least one of:

• Source code with class definitions and inheritance relationships
• A verbal or written description of the class hierarchy and how classes relate
• A UML diagram or design document describing the object model

Agent: Before starting, confirm whether you have access to source code or only a description. Code access enables deeper analysis (scanning for concrete class instantiation, checking method override patterns). A description enables principle-level analysis.

Context & Input Gathering