Java Unit Testing Skill

A house style for Java unit tests (JUnit 5 + AssertJ + Mockito), packaged as a tool-agnostic Agent Skill.

What it is

SKILL.md plus the references/ directory are the entire skill. SKILL.md holds the rules and stays high-level; the reference files hold detailed patterns and load on demand. Any agent that supports the Agent Skills format reads SKILL.md directly.

Two thin adapters route agents that use a different discovery convention to the same SKILL.md. They contain no rules of their own:

• AGENTS.md: for agents that read an AGENTS.md file.
• .kiro/steering/java-unit-testing.md: a Kiro steering rule scoped to Java test files.

Layout

java-unit-test-skill/
├── SKILL.md                     # rules and workflow
├── references/
│   ├── PATTERNS.md                # code for every test pattern
│   ├── ASSERTJ.md                 # AssertJ usage, traps, migration
│   ├── UNIT-TESTING-PRACTICES.md  # state-first testing, test doubles, determinism, coverage
│   └── CHECKLIST.md               # pre-flight checklist + pitfalls
├── versions.json                # assumed tool versions (update first when bumping)
├── LICENSE                      # Apache-2.0
├── AGENTS.md                    # adapter → SKILL.md
├── .kiro/steering/
│   └── java-unit-testing.md     # adapter → SKILL.md (scoped to *Test.java)
└── README.md

Install

Place the java-unit-test-skill/ folder where the agent looks for skills, then point the agent at it. Common locations:

• A skills directory the agent scans (the whole folder), so SKILL.md is discovered automatically.
• The repository root, alongside AGENTS.md, for agents that read AGENTS.md.
• A project's .kiro/steering/ directory (the steering adapter), for Kiro.

Keep the folder intact so the adapters can reach SKILL.md and references/.