Tdd
Introduces commands for test-driven development, common anti-patterns and skills for testing using subagents.
- Type
- Plugin
- Repository
- NeoLabHQ/context-engineering-kit
- GitHub stars
- 1.7k
- License
- GPL-3.0
- Repo last updated
- Aug 26, 2026
- Source file
- plugins/tdd/.claude-plugin/plugin.json
- Version
- 3.1.0
- Author
- Vlad Goncharov
What Tdd is
Tdd is a plugin published in the NeoLabHQ/context-engineering-kit repository on GitHub, which has about 1.7k stars. The repository describes itself as: “Hand-crafted Claude Code Skills focused on improving agent results quality. Compatible with OpenCode, Cursor, Antigravity, Gemini CLI, and others. Includes CodeRabbit open-source alternative.”
A plugin is a package that bundles skills, slash commands, subagents, hooks, and MCP connectors so they install together. Plugins are plain files with a manifest at .claude-plugin/plugin.json, and they work in both Claude Code and Claude Cowork.
Installing Tdd adds everything it ships in one step. Connectors inside a plugin still need to be connected separately, and hooks and subagents only run in Cowork and Claude Code, not in regular chat.
How to install Tdd
Claude Code
- Add the repository as a plugin marketplace: claude plugin marketplace add NeoLabHQ/context-engineering-kit
- Install the plugin: claude plugin install tdd@<marketplace-name>, using the marketplace name from the repository's .claude-plugin/marketplace.json.
- Restart the session if the new skills or commands don't appear straight away.
Claude Cowork
- Open Customize → Plugins and choose Add marketplace.
- Enter NeoLabHQ/context-engineering-kit (the owner/repo shorthand works for GitHub).
- Find Tdd in the list, click Install, then connect any connectors it needs from its Connectors tab.
New to extending Cowork? Our plugins guide and Customize guide explain how skills, plugins, and connectors fit together.
Inside the source file
An excerpt from plugins/tdd/.claude-plugin/plugin.json, shared under the repository's GPL-3.0 license. Read the full file on GitHub.
A disciplined approach to software development that ensures every line of production code is validated by tests written first. Introduces TDD methodology, anti-pattern detection, and orchestrated test coverage using specialized agents.
Focused on:
- Test-first development - Write tests before implementation, ensuring every feature is verified
- Red-Green-Refactor cycle - Systematic approach that builds confidence through failing tests
- Anti-pattern detection - Identifies common testing mistakes like mock abuse and test-only methods
- Agent-orchestrated coverage - Parallel test writing using specialized subagents for complex changes
Plugin Target
- Prevent regressions - Every change is backed by tests that catch future breaks
- Improve design quality - Hard-to-test code reveals design problems early
- Build confidence - Watching tests fail then pass proves they actually test something
- Accelerate development - TDD is faster than debugging untested code in production
Overview
The TDD plugin implements Kent Beck's Test-Driven Development methodology, proven over two decades to produce higher-quality, more maintainable software. The core principle is simple but transformative: write the test first, watch it fail, then write minimal code to pass.
The plugin is based on foundational works including Kent Beck's Test-Driven Development: By Example and the extensive research on TDD effectiveness.
Quick Start
# Install the plugin
/plugin install tdd@NeoLabHQ/context-engineering-kit
> claude "Use TDD skill to implement email validation for user registration"
# Manually make some changes that cause test failures
# Fix failing tests
> /fix-testsAfter Implementation
If you implemented a new feature but have not written tests, you can use the write-tests command to cover it.
> claude "implement email validation for user registration"
# Write tests after you made changes
> /write-testsUsage Examples
Commands
- /write-tests - Systematically add test coverage for all local code changes using specialized review and development agents
- /fix-tests - Systematically fix all failing tests after business logic changes or refactoring using orchestrated agents.
Skills
- test-driven-development - Test-Driven Development (TDD) skill. Comprehensive TDD methodology and anti-pattern detection guide that ensures rigorous test-first development.
- design-testing-strategy - Manual for agents that need to decide what best way to cover a given artifact with tests, while minimizing amount of work.
- test-coverage - Manual for choosing, applying, different types of coverage analysis (structural, mutation, requirements, API/integration) on an existing test suite.
Foundation
The TDD plugin is based on decades of research and practice demonstrating significant improvements in code quality and development efficiency:
Foundational Works
- Test-Driven Development: By Example by Kent Beck - The definitive guide to TDD methodology, introducing Red-Green-Refactor
- Refactoring: Improving the Design of Existing Code by Martin Fowler - Companion work on safe code transformation under test coverage
Before you install
- Read the whole file first. Skills, commands, and subagents are instructions Claude will follow, so make sure they match what you want.
- Check which tools, scripts, or MCP servers it uses. Local servers and scripts run with your permissions.
- Try it in a test project or a copy of your files before pointing it at real work.
- Pin the version you tested, and review changes before updating.
- Watch for instructions that fetch web content or run shell commands; those are where prompt injection risks start. See our prompt injection guide.
FAQ
What is Tdd?
Tdd is a plugin for Claude Code and Claude Cowork from the NeoLabHQ/context-engineering-kit repository on GitHub. Introduces commands for test-driven development, common anti-patterns and skills for testing using subagents.
How do I install Tdd in Claude Code?
Add the repository as a plugin marketplace: claude plugin marketplace add NeoLabHQ/context-engineering-kit Install the plugin: claude plugin install tdd@<marketplace-name>, using the marketplace name from the repository's .claude-plugin/marketplace.json. Restart the session if the new skills or commands don't appear straight away.
Can I use Tdd in Claude Cowork?
Open Customize → Plugins and choose Add marketplace. Enter NeoLabHQ/context-engineering-kit (the owner/repo shorthand works for GitHub). Find Tdd in the list, click Install, then connect any connectors it needs from its Connectors tab.
Is Tdd safe to install?
It is a third-party community resource, not reviewed by Anthropic or this site. Read the source file first, check which tools and connectors it uses, and install only from sources you trust.
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