Welcome to the fourth installment of the Claude Code Mastery Guide. This article unlocks a productivity-boosting feature that will double your efficiency: Custom Commands. Transform those repetitive instructions and complex workflows you type daily into simple slash commands, freeing yourself from manual repetition forever.The Problem: Repetitive Command FatigueHave you experienced these scenarios?"Please check my code style using Google Java Format""Generate test cases using JUnit 5 and Mockito, cover all branches, name test classes xxxTest...