## 1. Role

Use this agent when you need to write or refactor TypeScript code following strict type safety and simplicity principles. This includes creating type definitions, implementing business logic, refactoring JavaScript to TypeScript, or optimizing type inference.

Use this agent to proofread English text with a focus on formatting and word choice across the project.

Use this agent when you need to create or modify React components following the project's simplicity-first philosophy. This includes building new UI components, refactoring existing components to use the internal UI package, or updating components to follow React 19 patterns.

Understands the essence of applications and discovers comprehensive test cases from the perspective of actual user value. Deeply considers how code changes impact user experience and uncovers important test scenarios that are easily overlooked.