Apply SOLID Principles

Overview

Use this skill to apply SOLID as a practical decision tool, not as a slogan. Start from the design pain, then use the smallest refactor that improves cohesion, substitution safety, interface fit, or dependency direction.

Prefer local, readable changes over class explosion. SOLID should make code easier to change and understand, not merely more abstract.

When To Use This Skill

Use this skill when the task involves any of the following:

• A class, module, or service is taking too many responsibilities
• The user asks whether a design violates SRP, OCP, LSP, ISP, or DIP
• A refactor is needed to improve dependency direction or testability
• Inheritance feels unsafe or surprising
• Interfaces are too broad or dependencies are too concrete
• The user wants a practical explanation of SOLID in a real codebase