Tools

Forces red-green-refactor: write a test and watch it fail, then write the minimum code to pass. Any code written without a verified failing test gets deleted and redone. From the Superpowers workflow.

Test-driven development in vertical slices: agree on test seams with the user first, verify behavior only through public interfaces, and avoid listed anti-patterns such as implementation coupling and tautological tests. From Matt Pocock's skills collection.

A disciplined process for hard bugs and performance regressions: build a reliable reproduction loop, reproduce and minimize, form hypotheses, instrument to verify, then fix and add a regression test, redacting secrets in output. By Matt Pocock.

All-in-one JavaScript and TypeScript toolchain: a single bun binary is a Node.js-compatible runtime, package manager, test runner and script runner, with noticeably faster installs and test runs.

Python 3.12+ development plugin with python-pro, django-pro and fastapi-pro subagents, a project scaffolding command, and 16 skills on async, type safety, testing, packaging, uv and more. Part of the wshobson/agents marketplace.

Test-driven development plugin: /tdd-workflows:tdd-cycle and related commands move through red-green-refactor phases with a checkpoint for approval at each, plus TDD orchestrator and code reviewer subagents. Part of the wshobson/agents marketplace.

Reference for Vitest 5: config, CLI, the test, describe and expect APIs, hooks, mocking with vi, snapshots, coverage, fixtures, concurrency, filtering and tags, reporters, benchmarks, test environments, type testing and multi-project setups. Generated by Anthony Fu from the official docs.

The .NET team's official skill collection, grouped into plugins: ASP.NET Core, Blazor, MAUI, EF Core data access, MSBuild troubleshooting, performance diagnostics, testing, and framework upgrades and migrations. Maintained by Microsoft; install via the Claude Code or Codex plugin marketplace.

Agent skills maintained by the Flutter team: layered architecture, responsive layouts, fixing layout overflows, declarative routing, internationalization, JSON serialization, and widget and integration tests. Works alongside the Dart MCP server.

Official plugin from the Dart and Flutter teams that installs Flutter skills and the Dart MCP server together, covering layered architecture, responsive layouts, layout error fixes, widget and integration tests, routing and internationalization. Requires the Dart/Flutter SDK locally.

Uses hooks to enforce test-driven development in Claude Code: blocks implementation without a failing test, prevents code beyond what tests require, and can use lint results to push refactoring. Needs Node.js 22+. Still maintained, but the author suggests its successor Probity for new projects.

Lets agents work with Salesforce orgs authorized on your machine: SOQL queries, metadata deploy and retrieve, Apex test runs and permission set assignment, plus toolsets for LWC development. Maintained by Salesforce; authorize your org with the Salesforce CLI first.

Official testing skills from TestMu AI (formerly LambdaTest) covering 40+ frameworks including Selenium, Playwright, Cypress, Appium, pytest and JUnit, guiding agents to write unit, end-to-end and mobile tests. Runs locally; cloud cross-browser and real-device runs need an account.