kotlin-idioms

kotlin-idioms is a skill for Claude Code, Codex from mikel063093/kmp-quality-skills. It costs 0 tokens per session (1,883 once invoked), scanned A, original, no licence file.

A review of Kotlin code for idiomatic use of the language, including scope functions, data classes, sealed classes, extensions, delegation, inline and reified features, and null safety.

In plain words
What is it for?
Use it to improve Kotlin code, replace Java-like patterns, apply Kotlin language features correctly, and detect unsafe !! usage.
Why use it?
It catches Java-style patterns and risky uses of the non-null assertion operator, written as !!, that can cause runtime errors.

Skill for Claude CodeCodex

Which agent this was written for is unclear — body not stored (licence); the path alone says nothing.

Good fit Use it to improve Kotlin code, replace Java-like patterns, apply Kotlin language features correctly, and detect unsafe !! usage.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/mikel063093/kmp-quality-skills/kotlin-idioms
Install

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.

Any agent
npx skills add mikel063093/kmp-quality-skills --skill kotlin-idioms
Clone the repo
git clone --depth 1 https://github.com/mikel063093/kmp-quality-skills

Made for: Claude Code, Codex.

Wrote 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.

agentmods badge for kotlin-idioms

README.md
[![agentmods](https://agentmods.dev/badge/skills/mikel063093/kmp-quality-skills/kotlin-idioms/github.svg)](https://agentmods.dev/skills/mikel063093/kmp-quality-skills/kotlin-idioms)
Your own site
<a href="https://agentmods.dev/skills/mikel063093/kmp-quality-skills/kotlin-idioms"><img src="https://agentmods.dev/badge/skills/mikel063093/kmp-quality-skills/kotlin-idioms/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.

agentmods 80×15 button for kotlin-idioms

Your own site · 80×15
<a href="https://agentmods.dev/skills/mikel063093/kmp-quality-skills/kotlin-idioms"><img src="https://agentmods.dev/badge/skills/mikel063093/kmp-quality-skills/kotlin-idioms.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 0 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,883 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin unknown No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00000 $0.01883
Opus 5 $0.00000 $0.00941
Sonnet 5 $0.00000 $0.00377
Haiku 4.5 $0.00000 $0.00188

Measured 12d ago against content hash 26ee6df38e4b, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

kotlin-idioms 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 12d 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.

skills/kotlin-idioms/SKILL.md · 234 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

Changes

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.

  1. 12d ago First seen · 234 lines · 0 tokens per session scan A 26ee6df38e4b

Subscribe to this mod's changes

kotlin-idioms is a skill published in the GitHub repository mikel063093/kmp-quality-skills (2 stars, last pushed 6mo ago), with no licence file. It costs nothing until one of its globs matches a file; then it loads 1,883 tokens. 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.

Related

Other skills, from other repositories

axiom-audit-codable

Use when the user mentions Codable review, JSON encoding/decoding issues, data serialization audit, or modernizing legacy code.

CharlesWiltgen/Axiom · 32 tokens

axiom-swift-simplifier

Use when the user wants to simplify Swift code, reduce boilerplate, or make Swift more readable and idiomatic without changing behavior.

CharlesWiltgen/Axiom · 34 tokens

kotlin-api-design

Use when designing or reviewing Kotlin function ownership, member or extension functions, factories, single-field domain types, value classes, data classes, Kotlin Multiplatform expect/actual declarations, or platform service boundaries.

chrisbanes/skills · 46 tokens

kotlin-concurrency-and-flow

Use when writing or reviewing Kotlin coroutine scope ownership, raw Thread or Executor work, init launches, non-suspending launch APIs, runBlocking, cancellation, StateFlow, SharedFlow, Channel, stateIn, SharingStarted, state updates, or one-shot events.

chrisbanes/skills · 60 tokens

coding-best-practices

Reviews Swift/iOS code for adherence to modern Swift idioms, Apple platform best practices, architecture patterns, and code quality standards. Use when user mentions best practices, code review, clean code, refactoring, or wants to improve code quality.

rshankras/claude-code-apple-skills · 55 tokens

swift-concurrency-review

Review Swift 6 strict-concurrency and SwiftUI code for idiom and build-breaking issues - non-Sendable across actor boundaries, @MainActor witness vs nonisolated protocol requirements, Combine/ObservableObject usage, force-unwraps, #Predicate macro limits, the 6.3.x Binding IRGen crash, missing #if os() guards, and…

charlesjones-dev/claude-code-plugins-dev · 94 tokens