FreePublished on GitHub

kotlin

Kotlin (JetBrains 製プログラミング言語, kotlinlang.org) の言語仕様・標準ライブラリ・ツールチェーン。

null safety, data class, sealed class, 拡張関数, context parameters, スコープ関数 (let / run / apply / also / with), コレクション, Uuid, Duration (kotlin.time), kotlinx.coroutines (suspend, Flow), kotlinx.serialization (@Serializable, Json, ProtoBuf, CBOR), KGP, Maven, KSP, kapt, K2, KDoc。

The English summary is being prepared. Showing the original description.

Fandhe-AI/agent-reference-skills

See how to install

Files included (198)

SKILL.md7.7 KB
references/basics/annotations.md6.9 KB
references/basics/basic-syntax.md5.3 KB
references/basics/coding-conventions.md8.4 KB
references/basics/control-flow.md7.0 KB
references/basics/destructuring-declarations.md3.9 KB
references/basics/equality.md2.4 KB
references/basics/exceptions.md5.1 KB
references/basics/idioms.md5.5 KB
references/basics/keyword-reference.md8.6 KB
references/basics/kotlin-doc.md3.0 KB
references/basics/null-safety.md3.5 KB
references/basics/packages.md3.0 KB
references/basics/README.md2.9 KB
references/basics/returns.md2.4 KB
references/basics/visibility-modifiers.md2.9 KB
references/build-tools/build-tools-api.md2.6 KB
references/build-tools/gradle-best-practices.md2.4 KB
references/build-tools/gradle-binary-compatibility-validation.md3.1 KB
references/build-tools/gradle-compilation-and-caches.md7.5 KB
references/build-tools/gradle-compiler-options.md10.5 KB
references/build-tools/gradle-configure-project.md13.6 KB
references/build-tools/gradle-plugin-variants.md2.3 KB
references/build-tools/gradle.md1.6 KB
references/build-tools/kotlin-daemon.md2.4 KB
references/build-tools/maven-compile-package.md1.7 KB
references/build-tools/maven-configure-project.md8.4 KB
references/build-tools/maven-kotlin-compiler.md3.5 KB
references/build-tools/maven-set-dependencies.md4.0 KB
references/build-tools/maven.md1.6 KB
references/build-tools/README.md3.3 KB
references/classes-objects/classes.md3.8 KB
references/classes-objects/data-classes.md2.6 KB
references/classes-objects/delegated-properties.md5.8 KB
references/classes-objects/delegation.md1.7 KB
references/classes-objects/enum-classes.md5.4 KB
references/classes-objects/extensions.md5.5 KB
references/classes-objects/fun-interfaces.md2.7 KB
references/classes-objects/inheritance.md3.3 KB
references/classes-objects/inline-classes.md3.8 KB
references/classes-objects/interfaces.md2.7 KB
references/classes-objects/nested-classes.md1.6 KB
references/classes-objects/object-declarations.md4.7 KB
references/classes-objects/properties.md4.3 KB
references/classes-objects/README.md2.7 KB
references/classes-objects/sealed-classes.md5.1 KB
references/classes-objects/this-expressions.md3.3 KB
references/collections/collection-aggregate.md3.4 KB
references/collections/collection-elements.md2.7 KB
references/collections/collection-filtering.md2.3 KB
references/collections/collection-grouping.md2.2 KB
references/collections/collection-operations.md2.9 KB
references/collections/collection-ordering.md3.7 KB
references/collections/collection-parts.md3.1 KB
references/collections/collection-plus-minus.md1.3 KB
references/collections/collection-transformations.md3.2 KB
references/collections/collection-write.md2.3 KB
references/collections/collections-overview.md3.1 KB
references/collections/constructing-collections.md3.4 KB
references/collections/iterators.md2.4 KB
references/collections/list-operations.md4.2 KB
references/collections/map-operations.md3.6 KB
references/collections/ranges.md2.1 KB
references/collections/README.md3.9 KB
references/collections/sequences.md2.8 KB
references/collections/set-operations.md1.5 KB
references/compiler/all-open-plugin.md2.6 KB
references/compiler/command-line.md1.9 KB
references/compiler/compiler-execution-strategy.md2.2 KB
references/compiler/compiler-plugins-overview.md2.6 KB
references/compiler/compiler-reference.md11.6 KB
references/compiler/compose-compiler-migration-guide.md2.0 KB
references/compiler/compose-compiler-options.md1.8 KB
references/compiler/custom-compiler-plugins.md3.2 KB
references/compiler/k2-compiler-migration-guide.md4.8 KB
references/compiler/kapt.md6.9 KB
references/compiler/ksp-command-line.md3.4 KB
references/compiler/ksp-incremental.md3.9 KB
references/compiler/ksp-kapt-migration.md1.5 KB
references/compiler/ksp-kotlin-model.md4.4 KB
references/compiler/ksp-multi-round.md2.7 KB
references/compiler/ksp-multiplatform.md2.4 KB
references/compiler/ksp-overview.md3.1 KB
references/compiler/ksp-quickstart.md5.7 KB
references/compiler/ksp-reference.md17.1 KB
references/compiler/lombok.md2.8 KB
references/compiler/no-arg-plugin.md2.3 KB
references/compiler/power-assert.md5.5 KB
references/compiler/README.md4.3 KB
references/compiler/sam-with-receiver-plugin.md2.0 KB
references/coroutines/async-programming.md6.5 KB
references/coroutines/channels.md5.2 KB
references/coroutines/composing-suspending-functions.md4.0 KB
references/coroutines/coroutine-context-and-dispatchers.md6.4 KB
references/coroutines/coroutines-basics.md7.2 KB
references/coroutines/coroutines-cancellation.md7.8 KB
references/coroutines/coroutines-debugging.md6.7 KB
references/coroutines/coroutines-flow-operators.md5.1 KB
references/coroutines/coroutines-flow.md10.4 KB
references/coroutines/coroutines-guide.md2.3 KB
references/coroutines/coroutines-overview.md2.4 KB
references/coroutines/exception-handling.md5.2 KB
references/coroutines/README.md3.1 KB
references/coroutines/select-expression.md4.6 KB
references/coroutines/shared-mutable-state-and-concurrency.md3.7 KB
references/functions/context-parameters.md3.5 KB
references/functions/functions.md5.9 KB
references/functions/inline-functions.md2.9 KB
references/functions/lambdas.md4.7 KB
references/functions/operator-overloading.md3.5 KB
references/functions/README.md1.9 KB
references/functions/type-safe-builders.md3.6 KB
references/functions/unused-return-value-checker.md4.5 KB
references/functions/using-builders-with-builder-inference.md3.6 KB
references/java-interop/comparison-to-java.md3.7 KB
references/java-interop/java-interop.md17.1 KB
references/java-interop/java-to-kotlin-collections-guide.md9.6 KB
references/java-interop/java-to-kotlin-idioms-strings.md4.2 KB
references/java-interop/java-to-kotlin-interop.md10.9 KB
references/java-interop/java-to-kotlin-nullability-guide.md4.9 KB
references/java-interop/jvm-records.md3.3 KB
references/java-interop/README.md1.6 KB
references/releases/compatibility-guide-23.md8.4 KB
references/releases/compatibility-guide-24.md8.1 KB
references/releases/components-stability.md4.0 KB
references/releases/kotlin-evolution-principles.md5.8 KB
references/releases/kotlin-language-features-and-proposals.md3.2 KB
references/releases/README.md2.8 KB
references/releases/releases.md4.4 KB
references/releases/whatsnew23.md7.6 KB
references/releases/whatsnew2320.md7.3 KB
references/releases/whatsnew24.md11.0 KB
references/releases/whatsnew2420.md10.4 KB
references/serialization/README.md3.2 KB
references/serialization/serialization-cbor.md3.8 KB
references/serialization/serialization-configure-json-serialization.md1.8 KB
references/serialization/serialization-create-and-use-serializers.md12.6 KB
references/serialization/serialization-custom-formats.md7.9 KB
references/serialization/serialization-customization-options.md5.9 KB
references/serialization/serialization-get-started.md5.0 KB
references/serialization/serialization-json-configuration.md6.2 KB
references/serialization/serialization-json-elements.md3.5 KB
references/serialization/serialization-json-io-sources.md3.5 KB
references/serialization/serialization-polymorphism.md7.1 KB
references/serialization/serialization-protobuf.md4.6 KB
references/serialization/serialization-serialize-builtin-types.md2.9 KB
references/serialization/serialization-transform-json.md5.7 KB
references/serialization/serialization.md2.4 KB
references/stdlib/metadata-jvm.md6.0 KB
references/stdlib/opt-in-requirements.md3.7 KB
references/stdlib/read-standard-input.md1.8 KB
references/stdlib/README.md1.5 KB
references/stdlib/reflection.md5.6 KB
references/stdlib/scope-functions.md3.7 KB
references/stdlib/time-measurement.md4.4 KB
references/stdlib/uuids.md3.4 KB
references/types/arrays.md6.7 KB
references/types/booleans.md2.1 KB
references/types/characters.md2.7 KB
references/types/generics.md7.6 KB
references/types/numbers.md7.9 KB
references/types/README.md1.5 KB
references/types/strings.md5.3 KB
references/types/type-aliases.md3.2 KB
references/types/typecasts.md6.8 KB
references/types/types-overview.md2.6 KB
references/types/unsigned-integer-types.md3.5 KB
samples/collections-list-set-map.md1.5 KB
samples/control-flow-when.md961 B
samples/coroutines-cancellation.md2.6 KB
samples/coroutines-structured-concurrency.md2.5 KB
samples/enum-classes.md1.2 KB
samples/extension-functions.md1.2 KB
samples/flow-collect-and-cancel.md3.2 KB
samples/flow-error-handling.md2.5 KB
samples/functions-named-default-arguments.md1.2 KB
samples/gradle-jvm-project.md1.8 KB
samples/idioms-null-handling-expressions.md1.7 KB
samples/junit-kotlin-tests-gradle.md2.8 KB
samples/lambdas-with-receiver-dsl.md1.2 KB
samples/maven-kotlin-test-surefire-failsafe.md1.6 KB
samples/null-safety-patterns.md1.3 KB
samples/object-declarations-companion.md2.4 KB
samples/open-classes-inheritance.md1.9 KB
samples/README.md4.4 KB
samples/scope-functions.md1.8 KB
samples/sealed-class-when.md1.8 KB
samples/serialization-json-roundtrip.md1.5 KB
samples/serialization-json-streams.md1.8 KB
samples/serialization-polymorphism.md2.8 KB
scripts/compiler-plugins.md2.1 KB
scripts/gradle.md3.7 KB
scripts/install.md1.5 KB
scripts/kotlin-daemon.md1.6 KB
scripts/kotlinc.md3.0 KB
scripts/ksp.md3.4 KB
scripts/maven.md1.5 KB
scripts/README.md1.1 KB

SKILL.md (original)

Review the instructions the agent will receive before you install.

Kotlin

対象バージョン

対象	版	備考
Kotlin	2.4.21（2026-10-08、languageVersion / apiVersion 2.4）	`docs/v.list` で確認
kotlinx.coroutines	1.11.0
kotlinx.serialization	1.11.0
KSP	2.3.10

取得日: 2026-10-16
本文の一次ソース: kotlinlang.org/docs/llms.txt が列挙する Markdown twin https://kotlinlang.org/docs/_llms/<slug>.txt（例: basic-syntax.txt）。URL に版が無いため取得日を記録
照合用の原本
- Kotlin 本体ドキュメント: JetBrains/kotlin-web-site commit 0b10373a150997e9fbcd730a7e00ae8444cc8606（リリースタグが無いため SHA で pin）
- kotlinx.coroutines: Kotlin/kotlinx.coroutines commit 7e0d1b3e9ca83652427ae00dda7d1673f058a743（サイトは master から生成され、タグ 1.11.0 の docs は古い構成のため。保存した 14 件に 1.12 / EAP の記述は 0 件）
- kotlinx.serialization: Writerside ソースが公開されていないため twin のみ。補助として GitHub ガイドをタグ v1.11.0 で保存
除外した版: Kotlin 2.5.0-Beta1、kotlinx.serialization 1.12.0-RC

ディレクトリ構成

skills/kotlin/
  SKILL.md
  references/
    basics/                 # 構文・null safety・制御フロー・例外・KDoc・可視性（14 ページ）
      README.md
      basic-syntax.md  null-safety.md  control-flow.md  exceptions.md
      idioms.md  kotlin-doc.md  annotations.md  visibility-modifiers.md ...
    types/                  # 型システム（10 ページ）
      README.md
      numbers.md  strings.md  arrays.md  generics.md  typecasts.md  type-aliases.md ...
    classes-objects/        # クラス・オブジェクト（15 ページ）
      README.md
      classes.md  data-classes.md  sealed-classes.md  interfaces.md  extensions.md
      delegated-properties.md  object-declarations.md  inline-classes.md ...
    functions/              # 関数・ラムダ・DSL（8 ページ）
      README.md
      functions.md  lambdas.md  inline-functions.md  context-parameters.md
      type-safe-builders.md  operator-overloading.md ...
    collections/            # コレクション・シーケンス・Range（18 ページ）
      README.md
      collections-overview.md  collection-operations.md  sequences.md  ranges.md ...
    stdlib/                 # 標準ライブラリ補足（7 ページ）
      README.md
      scope-functions.md  opt-in-requirements.md  reflection.md  time-measurement.md  uuids.md ...
    java-interop/           # Java 相互運用（7 ページ）
      README.md
      java-interop.md  java-to-kotlin-interop.md  jvm-records.md ...
    coroutines/             # kotlinx.coroutines（14 ページ）
      README.md
      coroutines-basics.md  coroutines-flow.md  channels.md  exception-handling.md ...
    serialization/          # kotlinx.serialization（14 ページ）
      README.md
      serialization-get-started.md  serialization-configure-json-serialization.md
      serialization-polymorphism.md  serialization-protobuf.md ...
    build-tools/            # Gradle・Maven・Kotlin daemon（14 ページ）
      README.md
      gradle-configure-project.md  gradle-compiler-options.md  maven-configure-project.md ...
    compiler/               # コンパイラ・K2・コンパイラプラグイン・KSP・kapt（23 ページ）
      README.md
      compiler-reference.md  k2-compiler-migration-guide.md  ksp-overview.md  ksp-quickstart.md  kapt.md ...
    releases/               # リリース・互換性・What's new（10 ページ）
      README.md
      whatsnew24.md  whatsnew2420.md  compatibility-guide-24.md  components-stability.md ...
  samples/                  # 動く実例 22 件
    README.md
    null-safety-patterns.md  sealed-class-when.md  scope-functions.md
    coroutines-structured-concurrency.md  flow-collect-and-cancel.md
    serialization-json-roundtrip.md  gradle-jvm-project.md ...
  scripts/                  # コマンド集 7 件
    README.md
    install.md  kotlinc.md  gradle.md  maven.md  kotlin-daemon.md  ksp.md  compiler-plugins.md

探索手順

タスクからカテゴリを引き、カテゴリの README.md で目的のページを特定する。

下記マッピング表でタスクに対応するカテゴリを探す
そのカテゴリの references/{category}/README.md を参照して目的のページを特定する
該当ページの .md を Read して詳細を確認する
動く例が必要なら samples/README.md、実行コマンドが必要なら scripts/README.md を引く

タスク → カテゴリマッピング

タスク	カテゴリ	参照 README
基本構文・null safety・if / when / for・例外処理・可視性・KDoc を知りたい	basics	references/basics/README.md
数値・String・Array・ジェネリクス・型キャスト・typealias を知りたい	types	references/types/README.md
class・data class・sealed class・interface・拡張・委譲・object を知りたい	classes-objects	references/classes-objects/README.md
関数・ラムダ・inline・context parameters・DSL ビルダー・演算子オーバーロード	functions	references/functions/README.md
List / Set / Map の操作・変換・フィルタ・Sequence・Range	collections	references/collections/README.md
スコープ関数・opt-in・リフレクション・Duration・Uuid・標準入力	stdlib	references/stdlib/README.md
Java との相互運用・Java record・Java コレクションとの違い	java-interop	references/java-interop/README.md
suspend 関数・launch / async・Flow・Channel・キャンセル・例外	coroutines	references/coroutines/README.md
JSON / ProtoBuf / CBOR シリアライズ・カスタムシリアライザ・ポリモーフィズム	serialization	references/serialization/README.md
Gradle / Maven 設定・コンパイラオプション・Kotlin daemon	build-tools	references/build-tools/README.md
コンパイラオプション・K2 移行・KSP・kapt・all-open / no-arg 等のプラグイン	compiler	references/compiler/README.md
新バージョンの変更点・互換性ガイド・コンポーネント安定性	releases	references/releases/README.md
典型的な使い方を知りたい	samples	samples/README.md
インストール・CLI コマンドを知りたい	scripts	scripts/README.md

Reviews

No reviews yet. Tell others what you thought.

Comments

No login needed. Share how it worked for you, ask a question, or note where it did not run.

No comments yet. Be the first to write one.

More skills from this repository

amd-rocm

Free

AMD ROCm / HIP GPU コンピューティングリファレンス。 hipMalloc, hipLaunchKernelGGL, HIP Graph, hipGreenCtx, HIPRTC, hipify, rocBLAS, MIOpen, RCCL, hipThreads, libhipcxx, rocprofv3, amd-smi, rocminfo, TheRock / Core SDK 10, CDNA1-4 / RDNA1-4, MI300 / MI350 / MI350P, gfx942, Matrix Core, wave32/64。

The English summary is being prepared. Showing the original description.

Fandhe-AI/agent-reference-skills4Updated Oct 18, 2026

android-architecture

Free

Android アプリ開発 (Kotlin) の推奨アーキテクチャリファレンス。 Jetpack, androidx, UI layer, Domain layer, Data layer, state holder, UDF, SSOT, オフラインファースト, モジュール化, ViewModel, viewModelScope, SavedStateHandle, Lifecycle, repeatOnLifecycle, collectAsStateWithLifecycle, LiveData, Hilt による DI, Paging 3 によるページング処理。

The English summary is being prepared. Showing the original description.

Fandhe-AI/agent-reference-skills4Updated Oct 18, 2026

android-background-work

Free

Android アプリ開発 (Kotlin) のバックグラウンド・非同期処理リファレンス。 Jetpack androidx WorkManager: Worker, CoroutineWorker, WorkRequest, Constraints, WorkInfo, WorkContinuation, expedited work, テスト。 Service: フォアグラウンドサービス, バウンドサービス, AIDL, Messenger。 AlarmManager, PendingIntent, BroadcastReceiver, JobScheduler, Doze。 Kotlin コルーチン, Flow, StateFlow, SharedFlow, Channel。

The English summary is being prepared. Showing the original description.

Fandhe-AI/agent-reference-skills4Updated Oct 18, 2026

android-build-gradle

Free

Android アプリ開発 (Kotlin) の Gradle ビルドシステムリファレンス。 Android Gradle Plugin (AGP), Kotlin DSL (build.gradle.kts), version catalog, KSP, R8/ProGuard, App Bundle, baseline profile。

The English summary is being prepared. Showing the original description.

Fandhe-AI/agent-reference-skills4Updated Oct 18, 2026

android-compose-components

Free

Android Jetpack Compose (Kotlin) の androidx Material3 コンポーネントリファレンス。 Button, IconButton, FloatingActionButton, Checkbox, Switch, Slider, TextField, SearchBar, DropdownMenu, Chip, DatePicker, TimePicker, Card, Scaffold, Dialog, BottomSheet, TopAppBar, NavigationBar, NavigationRail, Tab, Snackbar, ProgressIndicator, Badge, Icon, MaterialTheme, ColorScheme, Typography, Shapes。

The English summary is being prepared. Showing the original description.

Fandhe-AI/agent-reference-skills4Updated Oct 18, 2026

android-compose-graphics-animation

Free

Android Jetpack Compose (Kotlin) のアニメーション・描画リファレンス。 androidx.compose.animation / graphics API。 AnimatedVisibility, AnimatedContent, animate*AsState, Animatable, AnimationSpec, Canvas, DrawScope, Brush, Path, Color, Image。

The English summary is being prepared. Showing the original description.

Fandhe-AI/agent-reference-skills4Updated Oct 18, 2026

See all skills by Fandhe-AI

Report a problem with this skill

Install

Install with a command

npx skills add https://github.com/Fandhe-AI/agent-reference-skills --skill kotlin

Paste it into your terminal and run it (requires Node.js). You can choose which agents to install it for, such as Claude Code or Codex.

Ask your agent

Please install the following Agent Skill.
https://github.com/Fandhe-AI/agent-reference-skills/tree/main/skills/kotlin

First review SKILL.md and the bundled files and confirm there is nothing suspicious (such as sending data externally or reading credentials). Then place it in ~/.claude/skills/kotlin/ for Claude Code, or ~/.agents/skills/kotlin/ for Codex.

Send this text to Claude Code or Codex as is. It checks the contents before installing.

View source on GitHub

Repository: Fandhe-AI/agent-reference-skills
Stars: 4
Forks: 1
Category: Data & AI
Original language: Japanese
Last updated: Oct 18, 2026

A skill is a set of instructions and scripts for an agent. cccskills does not guarantee that skills are safe. Review the contents before you install.

Files included (198)

SKILL.md (original)

Kotlin

対象バージョン

ディレクトリ構成

探索手順

タスク → カテゴリ マッピング

Reviews

Comments

More skills from this repository

amd-rocm

android-architecture

android-background-work

android-build-gradle

android-compose-components

android-compose-graphics-animation

タスク → カテゴリマッピング