Backend

Better Auth JWT verification for Python/FastAPI backends. Use when integrating Python APIs with a Better Auth TypeScript server via JWT tokens. Covers JWKS verification, FastAPI dependencies, SQLModel/SQLAlchemy integration, and protected routes.

Build cloud-native microservices - service discovery, config server, API gateway, resilience patterns

Verify README accuracy, completeness, and audience fit by testing claims against the actual codebase. Use when: (1) asked to verify documentation before a release, (2) significant changes to APIs or setup procedures might have invalidated documentation, (3) onboarding feedback or "it doesn't work" reports suggest documentation gaps, (4) README instructions haven't been verified against current codebase state.

Creates TypeScript modules following immutable, fluent API patterns with proper encapsulation.

This skill should be used when the user asks about "Minitest", "TDD", "test-driven development", "Rails testing", "writing tests", "test coverage", or testing strategies for Rails applications. Load this skill when implementing or reviewing tests.

Provides idiomatic Go programming expertise and best practices. Ensures clean, efficient, and maintainable code following official Go conventions. Specializes in concurrent programming patterns, interface design, error handling strategies, and performance optimization. Masters standard library usage and ecosystem integration. Use when: writing Go code (.go files), designing interfaces and struct types, implementing concurrent patterns (goroutines/channels), handling errors idiomatically, writing table-driven tests, creating Go modules, optimizing performance-critical code, managing dependencies with go.mod, implementing HTTP servers and clients, working with context propagation, or designing package APIs for public libraries.

Master Spring Boot with auto-configuration, REST APIs, JPA, security, testing, and production-ready features for enterprise applications.

Provides idiomatic Go programming expertise and best practices. Ensures clean, efficient, and maintainable code following official Go conventions. Specializes in concurrent programming patterns, interface design, error handling strategies, and performance optimization. Masters standard library usage and ecosystem integration. Use when: writing Go code (.go files), designing interfaces and struct types, implementing concurrent patterns (goroutines/channels), handling errors idiomatically, writing table-driven tests, creating Go modules, optimizing performance-critical code, managing dependencies with go.mod, implementing HTTP servers and clients, working with context propagation, or designing package APIs for public libraries.

Guide for creating high-quality MCP (Model Context Protocol) servers that enable LLMs to interact with external services through well-designed tools. Use when building MCP servers to integrate external APIs or services, whether in Python (FastMCP) or Node/TypeScript (MCP SDK). | 適切に設計されたツールを通じてLLMが外部サービスと対話できるようにする高品質MCP（Model Context Protocol）サーバーを作成するためのガイド。Python（FastMCP）またはNode/TypeScript（MCP SDK）で外部APIやサービスを統合するMCPサーバーを構築する際に使用

Use when user says "update story tree", "show story tree", "show me a map", "story map", "tree diagram", "show stories", "view stories", "list stories", or asks for story visualization or tree status - autonomously maintains hierarchical story backlog by analyzing git commits, identifying under-capacity nodes, and coordinating story generation to fill gaps. Works with SQLite database using closure table pattern, prioritizes shallower nodes first, and tracks implementation status through commit analysis.

Mandatory inspection procedures for understanding Rails codebase structure before writing any code. Use this skill FIRST before any code generation task to discover existing patterns, conventions, dependencies, and file organization in the target Rails project.

Python FastAPI patterns, Alembic migrations, Pydantic v2, and AI Engineering (raw patterns, LangChain, Google ADK). This skill should be used when working with Python APIs, database migrations, or AI/LLM applications.

Scrape Odoo forum solved threads to build error prevention guardrails and auto-fix scripts. Extract patterns from 1000+ solved issues to prevent common mistakes before deployment and auto-heal production problems. Combines web scraping, AI pattern extraction, preventive guardrails generation, and auto-patch scripts for Odoo custom development lifecycle.

Master asynchronous programming in Node.js with Promises, async/await, streams, and event-driven patterns for efficient non-blocking operations

Set up Flask REST API with flask-smorest, OpenAPI docs, blueprint architecture, and dataclass models. Use when creating a new Flask API server, building REST endpoints, or setting up a production API.

Build microservices - Spring Cloud, service mesh, event-driven, resilience patterns

Handle networking in Swift - URLSession, async/await, Codable, API clients, error handling

Apply consistent coding style, naming conventions, and code formatting across the NestJS API codebase. Use this skill when writing any TypeScript code in the apps/api/ or packages/shared/ directories, when naming variables, functions, classes, or files, when structuring imports and exports, or when following the project's ESLint and Prettier configurations. This includes enforcing strict TypeScript settings (no any, prefer-nullish-coalescing, prefer-optional-chain), using proper file naming patterns (kebab-case for files, PascalCase for classes), organizing imports alphabetically, and maintaining 120 character line width. Apply when writing any *.ts file, refactoring code, or reviewing code quality.

Browser automation using Playwright for web scraping, testing, screenshots, and interaction. Use when the user needs to navigate websites, fill forms, click buttons, extract web content, take screenshots, or automate browser tasks.

Expert sinusitis consultant. IMMEDIATELY search 10+ authoritative sources (UpToDate, AAO-HNS, EPOS, Mayo, PubMed/PMC, Cleveland Clinic, Hopkins, Springer, NORD, ENT Today, USA Sinus) for ANY sinus question. Use WebFetch to read sources deeply. Mark uncertainty explicitly.