> browse/registry

> rust-testing

Rust testing patterns for CLI applications, libraries, and frameworks. This skill should be used when writing, reviewing, or refactoring Rust tests including unit tests, integration tests, mocking, async testing, and CI integration. Triggers on tasks involving Rust testing, cargo test, mockall, proptest, tokio test, or test organization.

> ios-xcode

Xcode setup and tooling guidance for iOS 26 / Swift 6.2 clinic modular MVVM-C projects covering project configuration, SwiftData container wiring, testing, debugging, profiling, and distribution workflows. Use when configuring App-target infrastructure or day-to-day tooling around clinic architecture modules.

> skill-authoring

Design and development best practices for Claude Code skills, MCP tools, and AI agent capabilities. Use when creating skills, writing SKILL.md files, designing tool descriptions, or optimizing triggers. Triggers on "create a skill", "skill template", "write skill instructions", SKILL.md, metadata.json, progressive disclosure, trigger optimization, MCP tool design, or skill testing. Does NOT cover specific frameworks or languages (use dedicated skills).

> rails-testing

Ruby on Rails testing best practices for writing effective, maintainable test suites with RSpec. This skill should be used when writing, reviewing, or refactoring Rails tests to ensure proper test design, data management, and coverage patterns. Triggers on tasks involving RSpec specs, model tests, request specs, system tests, factory definitions, Capybara interactions, Sidekiq job tests, or test suite optimization. Complementary to rails-dev, ruby-optimise, and ruby-refactor skills.

> ue-testing-debugging

Use when writing automation tests, functional tests, or any test in Unreal Engine. Also use when the user asks about "UE_LOG", logging, log categories, assertion, check, ensure, verify, DrawDebug, debug draw, console command, profiling, Unreal Insights, stat commands, or debugging techniques. See ue-module-build-system for test module setup, and ue-cpp-foundations for general C++ logging patterns.

> go-interfaces

Use when defining or implementing Go interfaces, designing abstractions, creating mockable boundaries for testing, or composing types through embedding. Also use when deciding whether to accept an interface or return a concrete type, or using type assertions or type switches, even if the user doesn't explicitly mention interfaces. Does not cover generics-based polymorphism (see go-generics).

> go-style-core

Use when working with Go formatting, line length, nesting, naked returns, semicolons, or core style principles. Also use when a style question isn't covered by a more specific skill, even if the user doesn't reference a specific style rule. Does not cover domain-specific patterns like error handling, naming, or testing (see specialized skills). Acts as fallback when no more specific style skill applies.

> go-testing

Use when writing, reviewing, or improving Go test code — including table-driven tests, subtests, parallel tests, test helpers, test doubles, and assertions with cmp.Diff. Also use when a user asks to write a test for a Go function, even if they don't mention specific patterns like table-driven tests or subtests. Does not cover benchmark performance testing (see go-performance).

> style-guide

Analyze a codebase to extract its conventions, patterns, and style. Spawns specialized analyzer agents that each focus on one aspect (structure, naming, patterns, testing, frontend). Generates a comprehensive style guide that other skills can reference. Use when starting work on an unfamiliar codebase, or to create explicit documentation of implicit conventions.

> ros2-engineering-skills

Comprehensive ROS 2 engineering guide covering workspace setup, node architecture, communication patterns (topics/services/actions with QoS), lifecycle and component nodes, launch composition, tf2/URDF, ros2_control hardware interfaces, real-time constraints, Nav2, MoveIt 2, perception pipelines, simulation (Gazebo/Isaac Sim), security (SROS2/DDS), micro-ROS (MCU/RTOS), multi-robot systems (fleet management/Open-RMF), testing, debugging, deployment, and ROS 1 migration. Trigger whenever the user

> golang

Best practices for writing production Go code. Use when writing, reviewing, or refactoring Go code. Covers error handling, concurrency, naming conventions, testing patterns, performance optimization, generics, and common pitfalls. Based on Google Go Style Guide, Uber Go Style Guide, Effective Go, and Go Code Review Comments. Updated for Go 1.25.

> minecraft-testing

Write automated tests for Minecraft mods and plugins for 1.21.x. Covers NeoForge GameTests (@GameTest annotation, GameTestHelper assertions, test structure placement), Fabric game tests (fabric-gametest-api-v1), unit testing non-Minecraft logic with JUnit 5, MockBukkit for Paper/Bukkit plugin testing (mock server, mock player, event dispatching, inventory checking), integration testing with a test server via Gradle, and GitHub Actions CI workflows that run GameTests headlessly. Includes pattern

> e2e-runner

End-to-end testing specialist using Playwright. Use PROACTIVELY for generating, maintaining, and running E2E tests. Manages test journeys, quarantines flaky tests, uploads artifacts (screenshots, videos, traces), and ensures critical user flows work.

> tdd-workflow

Use this skill when writing new features, fixing bugs, or refactoring code. Enforces test-driven development with 80%+ coverage including unit, integration, and E2E tests.

> creating-financial-models

This skill provides an advanced financial modeling suite with DCF analysis, sensitivity testing, Monte Carlo simulations, and scenario planning for investment decisions

> browser-automation

Non-testing browser automation - web scraping, form filling, screenshot capture, PDF generation, workflow automation. For TESTING with Playwright, use e2e-playwright skill instead. Activates for web scraping, form automation, screenshot, PDF, headless browser, Puppeteer, Selenium, automation scripts, data extraction.

> terraform-skill

Use when working with Terraform or OpenTofu - creating modules, writing tests (native test framework, Terratest), setting up CI/CD pipelines, reviewing configurations, choosing between testing approaches, debugging state issues, implementing security scanning (trivy, checkov), or making infrastructure-as-code architecture decisions

> solidity-testing

[AUTO-INVOKE] MUST be invoked BEFORE writing or modifying any test files (*.t.sol). Covers test structure, naming conventions, coverage requirements, fuzz testing, and Foundry cheatcodes. Trigger: any task involving creating, editing, or running Solidity tests.

> aspnet-core

Build, review, refactor, or architect ASP.NET Core web applications using current official guidance for .NET web development. Use when working on Blazor Web Apps, Razor Pages, MVC, Minimal APIs, controller-based Web APIs, SignalR, gRPC, middleware, dependency injection, configuration, authentication, authorization, testing, performance, deployment, or ASP.NET Core upgrades.

> develop-web-game

Use when Codex is building or iterating on a web game (HTML/JS) and needs a reliable development + testing loop: implement small changes, run a Playwright-based test script with short input bursts and intentional pauses, inspect screenshots/text, and review console errors with render_game_to_text.