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.
npx skills add jabrena/plinth --skill 141-java-refactoring-with-modern-featuresgit clone --depth 1 https://github.com/jabrena/plinthWrote 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.
[](https://agentmods.dev/skills/jabrena/plinth/141-java-refactoring-with-modern-features)<a href="https://agentmods.dev/skills/jabrena/plinth/141-java-refactoring-with-modern-features"><img src="https://agentmods.dev/badge/skills/jabrena/plinth/141-java-refactoring-with-modern-features/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/jabrena/plinth/141-java-refactoring-with-modern-features"><img src="https://agentmods.dev/badge/skills/jabrena/plinth/141-java-refactoring-with-modern-features.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
- Socket pass
- Snyk pass
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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00148 | $0.00786 |
| Opus 5 | $0.00074 | $0.00393 |
| Sonnet 5 | $0.00030 | $0.00157 |
| Haiku 4.5 | $0.00015 | $0.00079 |
Grade A, and why
141-java-refactoring-with-modern-features 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 7d 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.
Copies of this mod
1 near-identical copy found in the catalogue:
- 141-java-refactoring-with-modern-features — 89% identical, 27 lines differ
How it starts
The opening of the file, as written. The whole thing — 67 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Modern Java Development Guidelines (Java 8+)
Identify and apply modern Java (Java 8+) refactoring opportunities to improve readability, maintainability, and performance.
What is covered in this Skill?
- Lambda expressions and method references (over anonymous classes)
- Stream API for declarative collection processing
Optionalfor null-safe APIsjava.timeAPI (replacingDate/Calendar)- Default interface methods,
vartype inference - Unmodifiable collection factory methods (
List.of(),Set.of(),Map.of()) - Text blocks for multi-line strings
- Java 25 Flexible Constructor Bodies (JEP 513)
- Java 25 Module Import Declarations (JEP 511)
Scope: The reference is organized by examples (good/bad code patterns) for each core area. Apply recommendations based on applicable examples.
Constraints
Before applying any modern Java refactoring, ensure the project compiles. If compilation fails, stop immediately — do not proceed until the project compiles successfully. After applying improvements, run full verification.
- MANDATORY: Run
./mvnw compileormvn compilebefore applying any changes - SAFETY: If compilation fails, stop immediately — do not proceed until the project compiles successfully
- VERIFY: Run
./mvnw clean verifyormvn clean verifyafter applying improvements - BEFORE APPLYING: Read the reference for detailed good/bad examples, constraints, and safeguards for each modern Java feature
- EDGE CASE: If request scope is ambiguous, stop and ask a clarifying question before applying changes
- EDGE CASE: If required inputs, files, or tooling are missing, report what is missing and ask whether to proceed with setup guidance
When to use this skill
- Review Java code for modern Java development
- Apply best practices for modern Java development in Java code
- Modernize Java code with records pattern matching or switch expressions
- Replace legacy idioms with modern Java features
- Adopt Java 8+ language features safely
What ships with it
1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- 7d ago First seen · 67 lines · 148 tokens per session scan A 31ea570469a4
141-java-refactoring-with-modern-features is a skill published in the GitHub repository jabrena/plinth (438 stars, last pushed yesterday), licensed Apache-2.0. It adds 148 tokens to every session and 786 once invoked, about $0.0007 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 2026-09-03.
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