Kotlin/kotlin-agent-skills is a collection of packaged instructions, scripts, and resources that help coding agents handle projects written in Kotlin. It is for developers using Kotlin, with skills covering areas such as backend frameworks and build tooling. The catalogue entries are the individual Kotlin-focused skills distributed from the repository.
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 Kotlin/kotlin-agent-skills --skill kotlin-tooling-java-to-kotlingit clone --depth 1 https://github.com/Kotlin/kotlin-agent-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/kotlin/kotlin-agent-skills/kotlin-tooling-java-to-kotlin)<a href="https://agentmods.dev/skills/kotlin/kotlin-agent-skills/kotlin-tooling-java-to-kotlin"><img src="https://agentmods.dev/badge/skills/kotlin/kotlin-agent-skills/kotlin-tooling-java-to-kotlin/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/kotlin/kotlin-agent-skills/kotlin-tooling-java-to-kotlin"><img src="https://agentmods.dev/badge/skills/kotlin/kotlin-agent-skills/kotlin-tooling-java-to-kotlin.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Socket pass
- Snyk pass
- NVIDIA SkillSpector 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 | $0.00100 | $0.01476 |
| Opus 5 | $0.00050 | $0.00738 |
| Sonnet 5 | $0.00020 | $0.00295 |
| Haiku 4.5 | $0.00010 | $0.00148 |
Grade A, and why
kotlin-tooling-java-to-kotlin 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 11d 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.
How it starts
The opening of the file, as written. The whole thing — 139 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Java to Kotlin Conversion
Convert Java source files to idiomatic Kotlin using a disciplined 4-step conversion methodology with 5 invariants checked at each step. Supports framework-aware conversion that handles annotation site targets, library idioms, and API preservation.
Workflow
digraph j2k_workflow {
rankdir=TB;
"User specifies files" -> "Step 0: Scan & Detect";
"Step 0: Scan & Detect" -> "Load framework guides";
"Load framework guides" -> "Step 1: Convert";
"Step 1: Convert" -> "Step 2: Write .kt";
"Step 2: Write .kt" -> "Step 3: Git rename";
"Step 3: Git rename" -> "Step 4: Verify";
"Step 4: Verify" -> "Next file?" [label="pass"];
"Step 4: Verify" -> "Fix issues" [label="fail"];
"Fix issues" -> "Step 1: Convert";
"Next file?" -> "Step 0: Scan & Detect" [label="batch: yes"];
"Next file?" -> "Done" [label="no more files"];
}
Step 0: Scan & Detect Frameworks
Before converting, scan the Java file's import statements to detect which frameworks are in use. Load ONLY the matching framework reference files to keep context focused.
Framework Detection Table
| Import prefix | Framework guide |
|---|---|
org.springframework.* |
SPRING.md |
lombok.* |
LOMBOK.md |
javax.persistence.*, jakarta.persistence.*, org.hibernate.* |
HIBERNATE.md |
com.fasterxml.jackson.* |
JACKSON.md |
io.micronaut.* |
MICRONAUT.md |
io.quarkus.*, javax.enterprise.*, jakarta.enterprise.* |
QUARKUS.md |
dagger.*, dagger.hilt.* |
DAGGER-HILT.md |
io.reactivex.*, rx.* |
RXJAVA.md |
org.junit.*, org.testng.* |
JUNIT.md |
com.google.inject.* |
GUICE.md |
retrofit2.*, okhttp3.* |
RETROFIT.md |
org.mockito.* |
MOCKITO.md |
What ships with it
15 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.
- assets/checklist.md 2.5 KB
- references/CONVERSION-METHODOLOGY.md 9.8 KB
- references/frameworks/DAGGER-HILT.md 4.3 KB
- references/frameworks/GUICE.md 4.5 KB
- references/frameworks/HIBERNATE.md 5.9 KB
- references/frameworks/JACKSON.md 7.1 KB
- references/frameworks/JUNIT.md 5.3 KB
- references/frameworks/LOMBOK.md 6.3 KB
- references/frameworks/MICRONAUT.md 3.3 KB
- references/frameworks/MOCKITO.md 7.7 KB
- references/frameworks/QUARKUS.md 3.8 KB
- references/frameworks/RETROFIT.md 4.4 KB
- references/frameworks/RXJAVA.md 5.6 KB
- references/frameworks/SPRING.md 6.3 KB
- references/KNOWN-ISSUES.md 9.5 KB
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.
- 11d ago First seen · 139 lines · 100 tokens per session scan A 5b372715adac
kotlin-tooling-java-to-kotlin is a skill published in the GitHub repository Kotlin/kotlin-agent-skills (1,039 stars, last pushed 17d ago), licensed Apache-2.0. It adds 100 tokens to every session and 1,476 once invoked, about $0.0005 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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