Combat systems often mix calculation logic with state management, making them hard to test and balance. This skill provides a proven dual-system architecture that separates pure combat math from state mutations, enabling easier testing, debugging, and balance adjustments.

Claude Code users need guardrails to prevent dangerous operations and enforce coding standards. Hookify rules provide pattern-based warnings and reminders during development. This skill teaches the syntax and best practices for creating effective Hookify rules.

Testing local web applications requires launching browsers, managing servers, and automating interactions. This skill provides Python Playwright scripts to verify frontend functionality, debug UI issues, capture screenshots, and collect browser console logs.

Create secure, efficient MCP servers that enable AI agents to interact with external APIs and services. Follow proven patterns for tool design, error handling, and evaluation.

Creating MCP servers requires understanding protocol specifications, tool design patterns, and evaluation techniques. This skill provides comprehensive guidance for building high-quality MCP servers in Python and TypeScript with working code examples and testing tools.

Transform creative ideas into original music compositions. Create algorithmic melodies, chords, and rhythms programmatically. Export finished pieces as MP3 files with realistic instrument sounds.

Creating elaborate HTML artifacts for Claude conversations requires modern frontend tooling. This skill provides automated scripts to initialize React projects with shadcn/ui and bundle them into single HTML files ready for artifact display.

React 19 introduces Actions, Server Components, and new hooks that simplify async operations and improve developer experience. This guide provides complete patterns for building, securing, and migrating React 19 applications.

Managing complex code changes with multiple dependent pull requests is challenging. This skill provides comprehensive guidance for using the Graphite CLI to create, submit, and synchronize stacked diffs efficiently.

Writing good commits and managing branches is hard. This skill provides clear guidance on Git worktree workflows, conventional commits, and pull request best practices so your history stays clean and readable.

Manual code reviews are time-consuming and often inconsistent. This skill provides automated analysis of code security, performance, maintainability, and test coverage to improve code quality systematically.

Bash scripts often fail silently or expose security vulnerabilities. This skill provides comprehensive standards for error handling, safe variable usage, and reliable script structure that prevent common mistakes.

Managing pull requests manually wastes time and creates inconsistent reviews. This skill automates PR creation, runs quality gates, and provides structured reviews to ensure every merge meets team standards.

Writing reliable end-to-end tests is challenging without proper guidance. This skill provides expert-level Playwright knowledge including locators, page objects, fixtures, and debugging techniques to help you build robust browser automation tests.

Users need guidance writing effective Jest tests for JavaScript and TypeScript applications. This skill provides comprehensive Jest expertise including configuration, matchers, mocking strategies, and React Testing Library patterns to write reliable, maintainable tests.

Create plugins that bundle agents, skills, commands, and hooks into distributable packages. Includes validation tools, templates, and best practices for secure plugin development.

Building Logseq plugins requires understanding the Plugin API, DB architecture, and compatibility patterns. This skill provides expert guidance on plugin structure, API namespaces, Datalog queries, and DB-version specific considerations.

Users need a way to create standardized, validated slash commands for their Claude Code workflows. This skill provides expert guidance on command structure, YAML schema, argument handling, and security best practices.

Building Claude Code agents requires understanding schema standards, security best practices, and proper tool configuration. This skill provides expert guidance for creating robust, secure agents following established patterns and includes validation to ensure quality before deployment.

Poor test quality leads to false confidence and hidden bugs. This skill provides automated analysis of test suites including coverage metrics, anti-pattern detection, and actionable improvement recommendations across any testing framework.