Kotest

Q: What is a Claude Code skill and how does the Kotest skill fit in?

A Claude Code skill is a SKILL.md file that lives under ~/.claude/skills/<name>/ and tells the Claude Code CLI agent how to perform a specific task (instructions, prompts, allowed tools). Skills are auto-discovered at session start. Kotest is one of 67,000+ skills indexed in the open ClaudSkills catalog, classified under the Engineering category. Learn more at https://claudskills.com/learn/what-is-skill-md/.

Category: Engineering · Sub-category: testing · Last updated: 2026-05-21

lang:kotlin lang:ruby

Helps write, migrate, and improve Kotlin tests using the Kotest testing framework. Covers test spec styles (FunSpec, DescribeSpec, BehaviorSpec, etc.), assertions (shouldBe, matchers, soft assertions), property-based testing (Arb, forAll, checkAll), data-driven testing, lifecycle hooks, extensions, coroutine testing, project configuration, and multiplatform setup. Use when the user mentions Kotest, kotest matchers, property testing with Arb, Kotest spec styles, shouldBe assertions, Kotlin test framework, or migrating from JUnit/TestNG/Spek to Kotest.

Security AStatic scan found no risk patternsHow grading works ›

From the source SKILL.md

Kotest is a flexible and comprehensive testing framework for Kotlin with multiplatform support. It is split into three standalone sub-projects that can be used independently or together:

What this skill does

Kotest is a community-contributed Claude Code skill in the testing sub-category. It ships as a SKILL.md file that Claude Code auto-discovers under ~/.claude/skills/kotest/ and loads when your prompt matches the skill's trigger.

When to invoke it: Use when the user mentions Kotest, kotest matchers, property testing with Arb, Kotest spec styles, shouldBe assertions, Kotlin test framework, or migrating from JUnit/TestNG/Spek to Kotest.

Who uses this skill

The Kotest Claude Code skill is built for software engineers, backend developers, full-stack teams, and technical leads building and maintaining production systems. It's part of ClaudSkills (also referred to as Claude Skills or Claude Code Skills) — the open community-curated registry of 161,000+ SKILL.md files for Anthropic's Claude Code agent and the wider Claude ecosystem (Claude API, Claude Agent SDK).

How to install

Free

Manual install (2 steps)

mkdir -p ~/.claude/skills/kotest
curl -L https://claudskills.com/skills/kotest/SKILL.md \
  -o ~/.claude/skills/kotest/SKILL.md

Or just download SKILL.md directly and drop it into ~/.claude/skills/kotest/. Claude Code auto-discovers it on next session.

Skills live at ~/.claude/skills/kotest/SKILL.md on macOS/Linux, or %USERPROFILE%\.claude\skills\kotest\SKILL.md on Windows. See the full install guide for step-by-step instructions.

📱 Install from your phone or desktop Telegram

Open @claudskills_bot on Telegram, tap Open Desktop App, and the desktop app installs this skill for you. Or share the bot link with a colleague — they get the same one-tap install. Learn more →

Pro

One-click install via the desktop app

The ClaudSkills desktop app installs any skill directly into ~/.claude/skills/ with one click — no terminal required. Pro starts at $9/mo or $149 lifetime.

Pro

For the full experience including quality scoring and one-click install features for each skill — upgrade to Pro.

See pricing → Download desktop app

Frequently asked questions

How do I install the Kotest Claude Code skill?

Install via the ClaudSkills desktop app (one click) or copy SKILL.md from the source repository to ~/.claude/skills/kotest/SKILL.md and restart Claude Code. Both flows are detailed at claudskills.com/install/.

What does the Kotest skill do?

Is this skill free to install?

Yes. ClaudSkills is an open registry — every skill keeps its source repository's license, and manual install via copy is free. ClaudSkills Pro ($9/mo, $79/yr, or $149 one-time) adds one-click install via the desktop app and a multi-signal Quality Score.

When should I use the Kotest skill?

Use Kotest when your Claude Code task falls under the Engineering category — specifically in the testing area. Claude Code auto-discovers installed skills and invokes the right one based on the task description, so you can also ask Claude directly (e.g. "use Kotest" or describe the task and let Claude pick). Browse related skills at /category/engineering/.

What is a Claude Code skill and how does the Kotest skill fit in?

A Claude Code skill is a SKILL.md file that lives under ~/.claude/skills/<name>/ and tells the Claude Code CLI agent how to perform a specific task (instructions, prompts, allowed tools). Skills are auto-discovered at session start. Kotest is one of 67,000+ skills indexed in the open ClaudSkills catalog, classified under the Engineering category. Learn more at /learn/what-is-a-claude-skill/.

Attribution & license

Source: https://github.com/kotest/kotest/blob/269a8ec5120ca24d573a7a28c2206cc1a8d293f4/skills/kotest/SKILL.md
License: Apache-2.0
Author: kotest
Website: https://kotest.io

Cite this skill

If you reference this skill in a blog post, paper, or documentation, you can cite it as:

APA

kotest. (2026). Kotest [Claude Code skill]. ClaudSkills. https://claudskills.com/skills/kotest/

BibTeX

@misc{kotest-2026,
  author    = {kotest},
  title     = {Kotest [Claude Code skill]},
  year      = {2026},
  publisher = {ClaudSkills},
  url       = {https://claudskills.com/skills/kotest/}
}

Embed this skill

Promote, attribute, or link this skill from your own README, blog post, or documentation. All three snippets are free to use — no sign-up, no API key. More distribution surfaces →

Badge

[![ClaudSkills](https://claudskills.com/badge/kotest.svg)](https://claudskills.com/skills/kotest/?utm_source=badge&utm_medium=readme&utm_campaign=skill_badge)

Security scan

Grade A · scanned 2026-07-27 — free static scan against the OWASP Agentic Skills Top 10.

No risk patterns were found in any of the ten OWASP-aligned categories. How grading works ›

✓ Prompt injection
✓ Data exfiltration
✓ Supply chain
✓ Reverse shell
✓ Credentials
✓ Execution
✓ Filesystem
✓ Persistence
✓ Obfuscation
✓ Network

Show this grade on your repo (click to copy):

[![Security: A](https://img.shields.io/badge/Security-A-2e7d32)](https://claudskills.com/skills/kotest/#security)

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Browse all Engineering skills in the ClaudSkills registry, or explore these other picks from the same category:

Browse all Engineering skills → Top 100 skills

Part of ClaudSkills — the open registry for Claude Skills & Claude Code Skills. · What's New · Install guide · About · llms.txt

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