1. Software Development

Generates failing tests first for new features or bug fixes using TDD, covering unit, integration, and edge cases.

Provides a standardized template and guidelines for structuring implementation tasks in a tasks.md file for consistent development tracking.

Fetches and verifies the latest official documentation to prevent outdated patterns and deprecated API usage during feature implementation.

Verifies current system date to ensure accuracy in date outputs, scheduling, and time-sensitive operations, avoiding knowledge cutoff errors.

A command-based tool for efficient software development tasks including component creation, API implementation, and bug fixes, optimized for token usage.

Manages Git worktrees for parallel development, creating worktrees with 'wt-' prefix and requiring user confirmation before creation.

Applies SOLID principles (single responsibility, open-closed, dependency injection) to ensure clean, maintainable code in all implementations.

Enforces Go backend best practices including clean architecture, dependency injection, and test-driven development for API and microservices implementation.

Performs software implementation tasks across frontend, backend, and testing roles as assigned, utilizing the /serena command for efficient development.

Provides integrated development tools for Next.js projects, including diagnostics, cache optimization, and automatic error fixes.

Provides TDD and testing guidance for Vitest, Jest, React Testing Library, and Playwright with enforced AAA pattern and Japanese test naming conventions.

Manages shadcn/ui components in React/Next.js projects, enabling search, addition, and management through components.json configuration.

Guides Go development with best practices including naming, error handling, concurrency, and testing per Google Style Guide and Effective Go.

Guides Next.js 16 and React 19 development with App Router, Server Components, TypeScript, Tailwind CSS, Prisma, and Vitest support.

Generates distinctive, production-ready frontend code for web components, pages, and applications, avoiding generic AI patterns.

Queries codebase architecture using README_AI.md index files to answer questions about project structure, feature locations, and module interactions.

Creates AI-optimized code indexes and documentation (README_AI.md) to make codebases searchable and accessible for developers.

Enforces strict type safety in TypeScript and Python, prohibiting 'any' types and supporting type guards for safer API and library integration.

Provides structured guidelines for reviewing and enhancing code quality in the YT Lite v3 project, emphasizing maintainability and best practices.

Conducts pre-implementation research to identify and evaluate existing libraries, ensuring efficient development by avoiding redundant code.

Guides developers in selecting optimal repository design strategies (data-oriented, requirement-oriented, or hybrid) based on business requirements.

Assists developers in building high-quality custom agent and skill definition files following GitHub Copilot best practices, including YAML frontmatter and MCP integration.

Enables unified error handling through Result Pattern, failure object creation, and layered strategies for robust applications.

Guides modern Python project setup with uv, ruff, mypy, FastAPI, and Docker configuration.