java SKILL.md skillA
java from ericrisco/rsc-harness is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add ericrisco/rsc-harness/java@git:20260729.8954115Pins git:20260729.8954115 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- ericrisco/rsc-harness
- Path
skills/java/SKILL.md- Versions recorded
- 3
- Latest version
- git:20260729.8954115, committed Jul 29, 2026
- First version recorded
- Jun 2, 2026
- Size
- 18,321 bytes
- Repository stars
- 236
- License
- MIT
Use when writing, reviewing or refactoring modern Java (21+, 25 LTS) — records and sealed interfaces as algebraic data types, exhaustive pattern-matching switch over instanceof ladders, virtual-thread concurrency, structured concurrency and ScopedValue replacing ThreadLocal, Stream and Optional pipelines, compact-constructor validation, parametrized JDBC, and the Maven/Gradle build surface. NOT Spring framework wiring (that is `spring-boot`).
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# Modern Java (21+) Write, review, and refactor Java the way the language is shaped today, not the way it was in 2014. Targets **Java 21+ with Java 25 as the current LTS** (released 2025-09-16, supported to 2033; Java 26 is the current non-LTS, 2026-03-17). "Modern" here means: records and sealed interfaces instead of JavaBeans and type hierarchies, exhaustive pattern-matching `switch` instead of `instanceof`+cast ladders, virtual threads instead of hand-tuned pools, and `ScopedValue` instead of `ThreadLocal`. If you are reaching for a telescoping constructor, a getter/setter bean, or a manual `ExecutorService` sized to a core count, stop. ## When to use / When NOT to use **Use when:** - Authoring, reviewing, or refactoring any `.java` file. - Modeling a domain: record vs class, sealed hierarchy vs enum, where immutability belongs. - Replacing `instanceof`+cast chains or visitor boilerplate with a pattern-matching `switch`. - Concurrency that blocks on I/O at scale: migrating thread pools / reactive chains to virtual threads, fan-out with structured concurrency, `ThreadLocal` -> `ScopedValue`. …
Read the whole file at its exact version.
How to install
mdr add ericrisco/rsc-harness/java@sha256:5e3a0f613d478848The line at the top of this page pins the label git:20260729.8954115, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_5xa44x7mrv4qei7r)
3 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 3 versions of this file, between Jun 2, 2026 and Jul 29, 2026, about one every 29 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20260729.8954115 latest | 2026-07-29 | 8954115 | 18,321 B | A | view · diff |
| git:20260615.5ea6bc3 | 2026-06-15 | 5ea6bc3 | 18,795 B | A | view · diff |
| git:20260602.c9dc7fb | 2026-06-02 | c9dc7fb | 18,767 B | A | view |
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (18321 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
ericrisco/rsc-harness · 236 stars · license MIT · pushed 2026-10-21 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_5xa44x7mrv4qei7r GET https://markdownregistry.com/api/v1/resolve?ref=ericrisco/rsc-harness/java GET https://markdownregistry.com/api/v1/blob/5e3a0f613d4788484725c1e94cb5600bcf782fa7f4261c29e622333c4f249a20
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.
More from ericrisco/rsc-harness
Every file in ericrisco/rsc-harness