java-development

A workflow guide for developing and reviewing Java projects and other software that runs on the Java Virtual Machine. It first checks the repository's build tools, tests, Java versions, modules, and project instructions before running commands or changing code.

In plain words
What is it for?
Use it for Java compilation, testing, debugging, code review, build failures, coverage, Spring Boot work, and Java continuous-integration tasks. It prefers the repository's own build wrapper and pinned toolchain settings.
Why use it?
It prevents incorrect assumptions about whether a project uses Maven or Gradle, which Java version it targets, or how its tests are meant to run. It also encourages reproducing and diagnosing failures before patching them.

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/lftpadilla/agent-dev-kit/java-development
Any agent
npx skills add LFTPadilla/agent-dev-kit --skill java-development
Clone the repo
git clone --depth 1 https://github.com/LFTPadilla/agent-dev-kit

Made for: Claude Code, Codex.

Per session 84 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,393 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original 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 $0.00084 $0.02393
Opus 5 $0.00042 $0.01196
Sonnet 5 $0.00017 $0.00479
Haiku 4.5 $0.00008 $0.00239

Measured yesterday against content hash 687bc67ac49b, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

java-development 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 yesterday.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/java-project-detect.sh), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

plugins/dev-skills/skills/java-development/SKILL.md · 213 lines

How it starts

The opening of the file, as written. The whole thing — 213 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Java development

Treat the repository as the source of truth. This skill is a workflow contract, not a request to convert a project to a preferred Java stack.

Non-negotiable contract

  1. Discover before executing. Read repository instructions, CI workflows, wrapper files, build descriptors, settings, module declarations, toolchain or release configuration, and existing test/quality plugins. Run scripts/java-project-detect.sh <repo> for an advisory, read-only summary.
  2. Use the project wrapper. Prefer ./mvnw or ./gradlew; do not substitute a globally installed Maven or Gradle. If both build systems are present, resolve the intended build root from repository instructions and CI rather than guessing. Use a system tool only when no wrapper exists, the repository documents that path, and the command is available.
  3. Honor the pinned JDK and target. Distinguish the JDK running the build or language server, the toolchain compiling/testing the project, and the bytecode/API target (--release, maven.compiler.release, or equivalent). Do not change compatibility settings merely to make the local machine pass.
  4. Diagnose before patching. Reproduce the exact compile/test failure, keep the full first relevant exception and Caused by chain, identify the failing module/task/phase, and separate environment/toolchain failures from product defects. Do not make speculative edits while a prerequisite is missing.
  5. Use a tight evidence loop. For behavior changes, add or identify the focused test, observe the expected failure, implement the smallest change, rerun that test, then the affected module and configured project/CI gates.
  6. Preserve project policy. Do not disable tests or analyzers, add blanket suppressions, lower coverage thresholds, weaken dependency verification, or rewrite generated files to obtain a green build.
  7. Verify independently. Inspect the final diff and generated-file status, then report exact commands, exit results, skipped checks, and prerequisites. A worker summary, IDE diagnostic, Graphify edge, or green focused test alone is not completion evidence.

Read the full file on GitHub · 213 lines

Files

What ships with it

2 files 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.

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. yesterday First seen · 213 lines · 84 tokens per session scan A 687bc67ac49b

Subscribe to this mod's changes

java-development is a skill published in the GitHub repository LFTPadilla/agent-dev-kit (2 stars, last pushed 4d ago), licensed MIT. It adds 84 tokens to every session and 2,393 once invoked, about $0.0004 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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