java-junit

java-junit is a skill for Claude Code, Codex from LucasMatuszewski/JSystems-SilkyCoders-1. It costs 19 tokens per session (698 once invoked), scanned A, original, no licence file.

Guidance for writing JUnit 5 unit tests in Java. Unit tests check small pieces of code in isolation, and data-driven tests run the same test with several inputs.

In plain words
What is it for?
Use it when writing or reviewing JUnit 5 tests, especially tests that need to run against multiple sets of data.
Why use it?
It helps you structure Java tests consistently and choose suitable testing practices. This can reduce repeated test code when checking many input cases.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/lucasmatuszewski/jsystems-silkycoders-1/java-junit
Any agent
npx skills add LucasMatuszewski/JSystems-SilkyCoders-1 --skill java-junit
Clone the repo
git clone --depth 1 https://github.com/LucasMatuszewski/JSystems-SilkyCoders-1

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for java-junit

README.md
[![agentmods](https://agentmods.dev/badge/skills/lucasmatuszewski/jsystems-silkycoders-1/java-junit.svg)](https://agentmods.dev/skills/lucasmatuszewski/jsystems-silkycoders-1/java-junit)
Your own site
<a href="https://agentmods.dev/skills/lucasmatuszewski/jsystems-silkycoders-1/java-junit"><img src="https://agentmods.dev/badge/skills/lucasmatuszewski/jsystems-silkycoders-1/java-junit.svg" alt="Measured on agentmods" height="20"></a>
Per session 19 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 698 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin unknown No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00019 $0.00698
Opus 5 $0.00010 $0.00349
Sonnet 5 $0.00004 $0.00140
Haiku 4.5 $0.00002 $0.00070

Measured 4d ago against content hash beeae246a2b1, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

java-junit scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 4d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.agents/skills/java-junit/SKILL.md · 64 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 4d ago First seen · 64 lines · 19 tokens per session scan A beeae246a2b1

Subscribe to this mod's changes

java-junit is a skill published in the GitHub repository LucasMatuszewski/JSystems-SilkyCoders-1 (2 stars, last pushed 3mo ago), with no licence file. It adds 19 tokens to every session and 698 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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