minitest-coder

minitest-coder is a skill for Claude Code from majesticlabs-dev/majestic-marketplace. It costs 60 tokens per session (1,904 once invoked), scanned A, original, no licence file.

A guide for writing Minitest tests for Ruby and Rails applications. Minitest is a Ruby testing library and supports both traditional test methods and a specification-style format.

In plain words
What is it for?
Use it to test new features, Rails integrations, and application code with fixtures and test doubles such as mocks.
Why use it?
It helps create consistent tests without applying RSpec conventions to a project that uses Minitest.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter.

Part of the majestic-rails plugin — 47 skills shipped together

Good fit Use it to test new features, Rails integrations, and application code with fixtures and test doubles such as mocks.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/majesticlabs-dev/majestic-marketplace/minitest-coder
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 majesticlabs-dev/majestic-marketplace --skill minitest-coder
Clone the repo
git clone --depth 1 https://github.com/majesticlabs-dev/majestic-marketplace

Made for: Claude Code.

Or install majestic-rails, the plugin that ships this one along with the rest of its 47 skills.

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 minitest-coder

README.md
[![agentmods](https://agentmods.dev/badge/skills/majesticlabs-dev/majestic-marketplace/minitest-coder/github.svg)](https://agentmods.dev/skills/majesticlabs-dev/majestic-marketplace/minitest-coder)
Your own site
<a href="https://agentmods.dev/skills/majesticlabs-dev/majestic-marketplace/minitest-coder"><img src="https://agentmods.dev/badge/skills/majesticlabs-dev/majestic-marketplace/minitest-coder/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 minitest-coder

Your own site · 80×15
<a href="https://agentmods.dev/skills/majesticlabs-dev/majestic-marketplace/minitest-coder"><img src="https://agentmods.dev/badge/skills/majesticlabs-dev/majestic-marketplace/minitest-coder.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 60 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,904 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 $0.00060 $0.01904
Opus 5 $0.00030 $0.00952
Sonnet 5 $0.00012 $0.00381
Haiku 4.5 $0.00006 $0.00190

Measured yesterday against content hash 6f91d87fe818, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

minitest-coder 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 yesterday.

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.

plugins/majestic-rails/skills/minitest-coder/SKILL.md · 314 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

Files

What ships with it

4 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.

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. yesterday First seen · 314 lines · 60 tokens per session scan A 6f91d87fe818

Subscribe to this mod's changes

minitest-coder is a skill published in the GitHub repository majesticlabs-dev/majestic-marketplace (50 stars, last pushed 2d ago), with no licence file. It adds 60 tokens to every session and 1,904 once invoked, about $0.0003 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 2026-09-11.

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