claude-skills is a collection of specialized skills that extends Claude Code for full-stack development. Developers use it for programming languages, frameworks, infrastructure, APIs, testing, DevOps, security, data and machine learning, platform tasks, and project workflows.
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 agentmods add skills/jeffallan/claude-skills/java-architectnpx skills add Jeffallan/claude-skills --skill java-architectgit clone --depth 1 https://github.com/Jeffallan/claude-skillsWrote 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/jeffallan/claude-skills/java-architect)<a href="https://agentmods.dev/skills/jeffallan/claude-skills/java-architect"><img src="https://agentmods.dev/badge/skills/jeffallan/claude-skills/java-architect.svg" alt="Measured on agentmods" height="20"></a>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 | $0.00067 | $0.01248 |
| Opus 5 | $0.00034 | $0.00624 |
| Sonnet 5 | $0.00013 | $0.00250 |
| Haiku 4.5 | $0.00007 | $0.00125 |
Grade A, and why
java-architect 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 5d 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
3 near-identical copies found in the catalogue:
- java-architect — 97% identical, 2 lines differ
- java-architect — 97% identical, 2 lines differ
- Qjava-architect — 86% identical, 139 lines differ
How it starts
The opening of the file, as written. The whole thing — 135 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Java Architect
Enterprise Java specialist focused on Spring Boot 3.x, microservices architecture, and cloud-native development using Java 21 LTS.
Core Workflow
- Architecture analysis - Review project structure, dependencies, Spring config
- Domain design - Create models following DDD and Clean Architecture; verify domain boundaries before proceeding. If boundaries are unclear, resolve ambiguities before moving to implementation.
- Implementation - Build services with Spring Boot best practices
- Data layer - Optimize JPA queries, implement repositories; run
./mvnw verify -pl <module>to confirm query correctness. If integration tests fail: review Hibernate SQL logs, fix queries or mappings, re-run before proceeding. - Security & config - Apply Spring Security, externalize configuration, add observability; run
./mvnw verifyafter security changes to confirm filter chain and JWT wiring. If tests fail: checkSecurityFilterChainbean order and token validation config, then re-run. - Quality assurance - Run
./mvnw verify(Maven) or./gradlew check(Gradle) to confirm all tests pass and coverage reaches 85%+ before closing. If coverage is below threshold: identify untested branches via JaCoCo report (target/site/jacoco/index.html), add missing test cases, re-run.
Reference Guide
Load detailed guidance based on context:
| Topic | Reference | Load When |
|---|---|---|
| Spring Boot | references/spring-boot-setup.md |
Project setup, configuration, starters |
| Reactive | references/reactive-webflux.md |
WebFlux, Project Reactor, R2DBC |
| Data Access | references/jpa-optimization.md |
JPA, Hibernate, query tuning |
| Security | references/spring-security.md |
OAuth2, JWT, method security |
| Testing | references/testing-patterns.md |
JUnit 5, TestContainers, Mockito |
Constraints
MUST DO
- Use Java 21 LTS features (records, sealed classes, pattern matching)
- Apply database migrations (Flyway/Liquibase)
- Document APIs with OpenAPI/Swagger
- Use proper exception handling hierarchy
- Externalize all configuration (never hardcode values)
What ships with it
5 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.
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.
- 5d ago First seen · 135 lines · 67 tokens per session scan A 6e38cf7391e2
java-architect is a skill published in the GitHub repository Jeffallan/claude-skills (11,307 stars, last pushed 28d ago), licensed MIT. It adds 67 tokens to every session and 1,248 once invoked, about $0.0003 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 2026-08-30.
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