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/heapy/kortex/kotlin-toolchainnpx skills add Heapy/kortex --skill kotlin-toolchaingit clone --depth 1 https://github.com/Heapy/kortexWhat 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 | $0.00148 | $0.05504 |
| Opus 5 | $0.00074 | $0.02752 |
| Sonnet 5 | $0.00030 | $0.01101 |
| Haiku 4.5 | $0.00015 | $0.00550 |
Grade A, and why
kotlin-toolchain 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 2d 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 — 395 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Kotlin Toolchain
Use this skill for JetBrains Kotlin Toolchain work: declarative YAML build configuration, the kotlin CLI, product
types, dependency wiring, multiplatform layout, publishing, and local build plugins.
Do not apply this skill to Gradle or Maven build editing unless the task is explicitly about converting a Maven project
to Kotlin Toolchain. Kotlin Toolchain is not Gradle, not Maven, and not the old Amper *.amper syntax.
Source Snapshot
This skill is generated from the official upstream docs for v0.12.0, the default supported version:
- Repository:
https://github.com/JetBrains/kotlin-toolchain - Ref:
v0.12.0 - SHA:
2039c5371bf5812f0061b2b11b6581b4e9de3a97 - Full aggregate:
generation/upstream-docs-v0.12.0.md - Generation notes:
generation/generation-steps.md
Statements here come from those docs, from the v0.12.0 release notes, and from spot-checks against the tagged source
tree. Where the docs lag the code, this skill follows the code and says so.
At v0.12.0 release time the upstream main docs matched this tag except for one line, so there is no separate
main/dev snapshot. Older guidance for v0.11.x is kept in SKILL-0.11.md for projects still pinned
there. Do not mix the two: the // path notation, nested templates, and KMP publishing all changed in 0.12.
The project is Alpha and the docs move quickly. Treat defaults and edge-case syntax as version-sensitive. When precision
matters, inspect the local project, run ./kotlin show ..., and grep the pinned aggregate (~300 KB — search it, do not
read it whole).
Internal names still contain Amper in expected places: jvm/amper-plugin, org.jetbrains.amper.plugins, and some
distribution paths. Do not rename those to kotlin. The YouTrack project, however, moved from AMPER to KTC.
Reference Map
SKILL.md carries the operational base. Load a reference only when the task goes past it.
| Reference | Load it for |
|---|---|
references/cli.md |
CLI commands and flags, wrapper install, provisioning, cache dirs, JDK provisioning |
references/project-model.md |
project.yaml, module.yaml keys, path notation, module layout |
references/product-types.md |
Per-product-type detail: entry points, build output, packaging limits |
references/dependencies.md |
Dependency notation, scopes, classifiers, catalogs, repositories |
references/settings.md |
Full settings tree, defaults table, compiler knobs |
references/builtin-tech.md |
Compose, serialization, Ktor, Spring, RPC, DataFrame, Power Assert, KSP, Lombok, Parcelize |
references/multiplatform.md |
Platform hierarchy, aliases, propagation, cinterop |
references/templates.md |
Nested templates, precedence, merging, conflict resolution |
references/publishing.md |
JVM and KMP publishing, Maven Central, mavenLocal, signing |
references/plugins.md |
Authoring jvm/amper-plugin modules, plugin.yaml, task actions |
references/maven-migration.md |
convert-project, mavenPlugins, migration gaps |
references/migrating-0.11-to-0.12.md |
What breaks when a project moves from 0.11.x to 0.12.0 |
references/known-issues.md |
Tracked defects and workarounds — check before diagnosing odd behavior |
references/codex-sandbox-caches.md |
Running the toolchain in a Codex workspace-write sandbox |
What ships with it
20 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.
- agents/openai.yaml 185 B
- generation/generation-steps.md 15 KB
- generation/upstream-docs-v0.11.1.md 297 KB
- generation/upstream-docs-v0.12.0.md 335 KB
- references/builtin-tech.md 7.2 KB
- references/cli.md 6.7 KB
- references/codex-sandbox-caches.md 3.0 KB
- references/dependencies.md 8.2 KB
- references/known-issues.md 3.9 KB
- references/maven-migration.md 6.7 KB
- references/migrating-0.11-to-0.12.md 9.0 KB
- references/multiplatform.md 6.3 KB
- references/plugins.md 9.1 KB
- references/product-types.md 7.4 KB
- references/project-model.md 5.1 KB
- references/publishing.md 5.6 KB
- references/settings.md 7.7 KB
- references/templates.md 5.8 KB
- scripts/aggregate-upstream-docs.sh 1.5 KB runs code
- SKILL-0.11.md 23 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.
- 2d ago First seen · 395 lines · 148 tokens per session scan A 3d32f901c92e
kotlin-toolchain is a skill published in the GitHub repository Heapy/kortex (6 stars, last pushed 4d ago), licensed Apache-2.0. It adds 148 tokens to every session and 5,504 once invoked, about $0.0007 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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