描述
Use this skill when the user asks about domain modeling, primitive obsession, parse-don't-validate, semantic types, value objects, or making invalid states unrepresentable. Triggers on: "review for domain issues", "primitive obsession", "design domain types", "value object", "newtype wrapper", "semantic type", "make invalid states unrepresentable", "bool-as-state", requests to replace raw strings/ints with proper types, requests to fix swappable parameters, or any code review focusing on type safety and domain integrity. Also activates during TDD domain review phases. NOT for general code review (style, formatting), debugging, database schema design, or design patterns unrelated to domain type modeling.