AI Coding Skills for Ruby

Code review automation for TypeScript, JavaScript, Python, Go, Swift, Kotlin, C#, .NET, Java, C, C++, Rust, Ruby, PHP, and Dart/Flutter. Analyzes PRs for complexity and risk, checks code quality for SOLID violations and code smells, generates review reports. Use when reviewing pull requests, analyzing code quality, identifying issues, generating review checklists.

Configure linting, formatting, and editor integration for any stack. Sets up ESLint 9 or Biome for JS/TS, Ruff for Python, golangci-lint for Go, Clippy for Rust, RuboCop for Ruby, or dart analyze for Flutter. Adds Prettier or equivalent formatter, .editorconfig, and VS Code format-on-save. Use when you need to add a linter, fix formatting inconsistencies, migrate from legacy lint tools, or set up code style enforcement.

Auto-detects the current project's technology stack and hot-loads context-appropriate skills at session start using Claude Code's SessionStart hook with reloadSkills: true. Detects Node.js/TypeScript, Next.js, Python, Rust, Go, Ruby, and monorepo layouts. Emits a .claude/dynamic-context.md with the detected stack and recommended skill list, then signals Claude Code to reload skills before the first agent turn.

Grades a specified set of test methods individually and produces a concise table mapping each test (fully-qualified name) to a letter grade (A–F), a score band, and a one-line note — designed to be posted as a PR comment. Use when the caller wants per-test feedback on a curated list of methods (for example, the new or modified tests in a pull request), not a suite-wide audit. Polyglot: .NET, Python, TS/JS, Java, Go, Ruby, Rust, Swift, Kotlin, PowerShell, C++. Input is a list of test methods (or method bodies / file+line spans); output is a compact markdown table plus a short summary. DO NOT USE FOR: full suite audits (use test-quality-auditor agent or test-anti-patterns), writing new tests (use code-testing-generator agent or writing-mstest-tests), fixing failures, or measuring code coverage.

Performs pseudo-mutation analysis on production code in any language to find gaps in existing tests. Use when the user asks to find weak or shallow tests, discover untested edge cases, or check whether tests would catch a bug — e.g. "would my tests catch it if someone changed the code", "would a subtle logic or boundary change slip past the current tests", "are my tests strong enough to catch a subtle bug". Evaluates test effectiveness through mutation-style reasoning: analyzes mutation points (boundaries, boolean flips, null returns, exception removal, arithmetic changes) and checks whether tests would detect each. Polyglot: .NET, Python, TS/JS, Java, Go, Ruby, Rust, Swift, Kotlin, PowerShell, C++. DO NOT USE FOR: writing new tests (use code-testing-agent, or writing-mstest-tests for MSTest), detecting anti-patterns (use test-anti-patterns), measuring assertion diversity (use assertion-quality), or running actual mutation testing tools (Stryker, mutmut, PIT, cargo-mutants).

Parse-only static analysis that pairs source files with the tests referencing them and emits JSON listing untested files ordered by API surface, each with a suggested_test_path. Roslyn engine for C#/.NET (namespace-aware), tree-sitter engine for polyglot repos (Python, TS/JS, Go, Java, Rust, Ruby). USE FOR: where to write tests next, which files have no tests, find untested code, build a source-to-test pairing map, prioritized test-gap worklist. DO NOT USE FOR: line/branch coverage or CRAP risk (use coverage-analysis); whether existing tests are strong (use test-gap-analysis or assertion-quality).

Ruby development guidelines covering idiomatic code style, Ruby 3.x features, testing with RSpec, and best practices for building maintainable Ruby applications.

RSpec testing best practices for Ruby and Rails applications, covering test organization, data management, and isolation patterns.

Audits an existing test file or suite in any language for anti-patterns and quality issues — produces a severity-ranked report (Critical/Warning/Info). INVOKE whenever asked to audit or review tests, find what's wrong with a suite, judge whether tests are any good, or check for: tests that pass but verify nothing, missing assertions, swallowed exceptions, self-comparing / tautological assertions, coverage-touching tests, broad exceptions, flaky or order-dependent tests (Thread.Sleep, DateTime.Now, shared state), duplicated tests, or magic values — in .NET, Python/pytest, TS/Jest, Java, Go, Ruby or C++. DO NOT USE FOR: writing new tests (use code-testing-agent, or writing-mstest-tests for MSTest); running tests (use run-tests); migration; assertion-diversity metrics (use assertion-quality); coverage/CRAP metrics (use coverage-analysis); the testsmells.org academic catalog (use test-smell-detection); fixing or modernizing MSTest tests, assertions, attributes, or lifecycle (use writing-ms

Full Sentry SDK setup for Ruby. Use when asked to add Sentry to Ruby, install sentry-ruby, setup Sentry in Rails/Sinatra/Rack, or configure error monitoring, tracing, logging, metrics, profiling, or crons for Ruby applications. Also handles migration from AppSignal, Honeybadger, Bugsnag, Rollbar, or Airbrake. Supports Rails, Sinatra, Rack, Sidekiq, and Resque.

Expert in Ruby and Rails development with conventions and best practices

Detects timing side-channel vulnerabilities in cryptographic code. Use when implementing or reviewing crypto code, encountering division on secrets, secret-dependent branches, or constant-time programming questions in C, C++, Go, Rust, Swift, Java, Kotlin, C#, PHP, JavaScript, TypeScript, Python, or Ruby.

Ruzzy is a coverage-guided Ruby fuzzer by Trail of Bits. Use for fuzzing pure Ruby code and Ruby C extensions.

Deep-dive audit using the full testsmells.org 19-smell academic catalog for tests in any language. Every finding maps to a named, citable smell from the research literature (Assertion Roulette, Duplicate Assert, Mystery Guest, Eager Test, Sensitive Equality, Conditional Test Logic, Sleepy Test, Magic Number Test, etc.) with research-backed severity. Polyglot: .NET (MSTest/xUnit/NUnit/TUnit), Python (pytest/unittest), TS/JS (Jest/Vitest/Mocha/node:test), Java (JUnit/TestNG), Go, Ruby (RSpec/Minitest), Rust, Swift, Kotlin (JUnit/Kotest), PowerShell (Pester), C++ (GoogleTest/Catch2). INVOKE ONLY when explicitly asked for the testsmells.org 19-smell academic catalog or citable smell names from the literature. DO NOT USE FOR: general or pragmatic audits — use test-anti-patterns; writing new tests (use code-testing-agent, or writing-mstest-tests for MSTest); running tests (use run-tests); framework migration.

Analyzes test suites in any language and tags each test with standardized traits (positive, negative, critical-path, boundary, smoke, regression, integration, performance, security). Use when the user wants to categorize, audit, or label tests with traits. Works across .NET (MSTest/xUnit/NUnit/TUnit), Python (pytest), TS/JS (Jest/Vitest), Java, Go, Ruby, Rust, Swift, Kotlin, PowerShell, and C++ — auto-editing when the framework has canonical tag syntax, otherwise report-only. Do not use for writing new tests, running tests, or migrating frameworks.

Analyzes the variety and depth of assertions across test suites in any language. Use when the user asks to evaluate assertion quality, find shallow tests, identify assertion-free tests (no assertions or only trivial ones like Assert.IsNotNull / toBeTruthy()), flag self-referential or tautological assertions, measure assertion diversity, or audit whether tests verify different facets of behavior. Polyglot: .NET, Python, TS/JS, Java, Go, Ruby, Rust, Swift, Kotlin, PowerShell, C++. DO NOT USE FOR: writing new tests (use code-testing-agent / writing-mstest-tests), mutation reasoning about whether tests would catch a bug (use test-gap-analysis), or a general severity-ranked anti-pattern audit (use test-anti-patterns), fixing or rewriting assertions, or writing, fixing, or modernizing MSTest tests, assertions, or attributes (use writing-mstest-tests).