JVM & .NET

The top-rated launch-quality JVM & .NET skill for AI agents is kotlin-coroutines-skill (grade B), followed by kotlin-in-action and java-concurrency. Skillspace rates 287 JVM & .NET skills; 70 are launch-quality.

Java, Kotlin, Scala, C#, .NET: language practice and ecosystems.

Launch-quality skills first, then by grade, then by our Skill Score, which adds judge reviews, test results, GitHub stars and adoption.

  1. kotlin-coroutines-skill B
  2. kotlin-in-action B
  3. java-concurrency B
  4. native B
  5. effective-kotlin B
  6. including-generated-files C
  7. gsap-utils C
  8. symbols-api C
  9. csharp-server C
  10. dotnet-core-expert C
  11. code-style C
  12. item-management C
  13. dotnet-aot-compat C
  14. csharp-scripts C
  15. sevenzip-format C
  16. kotlin-context-parameters C
  17. arrow-resource C
  18. java-developer C
  19. arrow-typed-errors C
  20. mps-aspect-constraints C
  21. csharp-nullable-reference-types C
  22. dynamo-dotnet-expert C
  23. cats-mtl-typed-errors C
  24. kotlin-coroutines C
  25. java-best-practices C

Frequently asked questions

What is the best JVM & .NET skill for AI agents?

The top-rated launch-quality JVM & .NET skill for AI agents is kotlin-coroutines-skill (grade B), followed by kotlin-in-action and java-concurrency. Skillspace rates 287 JVM & .NET skills; 70 are launch-quality.

How does Skillspace rate JVM & .NET skills?

Skillspace grades every JVM & .NET skill from A to F with a published scoring engine that reads the skill's SKILL.md: architecture and maturity make the score, and a security scan can cap it. In crowded categories, a judge model also compares the strongest contenders side by side, and some skills are tested head-to-head on real tasks against other skills in the same category (including a deliberately weak one) and a no-skill baseline. Launch-quality skills are graded A to C with a clean safety verdict, and not excluded by a quality filter: the filters catch skills our model's safety screen flags for prompt injection, guardrail bypass, harmful content or credential exposure; test fixtures and attack benchmarks; skills written only for the repository they live in; templates and stubs; and near-duplicate variants and copies of other skills. Ratings were last updated on 24 September 2026; the full method is on the methodology page.

Are JVM & .NET skills safe to install?

Of the 287 JVM & .NET skills Skillspace rates, 286 passed its safety scan and 1 is flagged for review. Each skill's page shows its safety verdict. A pass is not a guarantee: the scan reads only the skill's SKILL.md, not the scripts or other files it ships, and looks for patterns such as piping a remote script into a shell, reading credentials or hiding actions from the user. Skills are third-party code that Skillspace indexes but does not host or endorse, so read a skill's source on GitHub before you install it.

Skillspace indexes and rates skills; it does not host or endorse them. Run third-party skills at your own risk.