ruby SKILL.md skillA
ruby from ericrisco/rsc-harness is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add ericrisco/rsc-harness/ruby@git:20260729.baa11e7Pins git:20260729.baa11e7 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- ericrisco/rsc-harness
- Path
skills/ruby/SKILL.md- Versions recorded
- 2
- Latest version
- git:20260729.baa11e7, committed Jul 29, 2026
- First version recorded
- Jun 2, 2026
- Size
- 12,763 bytes
- Repository stars
- 505
- License
- MIT
Use when writing or refactoring plain Ruby outside Rails — scripts, CLIs, gems, libraries: Enumerable chains and blocks, module mixins and value objects, Bundler/gemspec packaging, whether metaprogramming earns its keep, Minitest or RSpec, Ruby 3.4/4.0 frozen-string hygiene. NOT Rails, ActiveRecord, or ActiveSupport idioms (that is `rails`).
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# Idiomatic Ruby, the language Write Ruby a senior Rubyist would sign off on: expression-oriented, block-driven, leaning on `Enumerable` and `Comparable` instead of hand-rolled loops, with `frozen_string_literal` hygiene and a real `Gemfile`/`.gemspec` when you package. This is **Ruby the language and its non-Rails ecosystem** — blocks, modules, gems, metaprogramming, Minitest/RSpec. Delegate: Rails apps, ActiveRecord models, controllers, migrations, views, Hotwire — anything that loads Rails or uses ActiveSupport/ActiveRecord idioms — to [`rails`](../rails/SKILL.md); the same task in another language to [`python`](../python/SKILL.md), [`go`](../go/SKILL.md), [`rust`](../rust/SKILL.md), [`elixir`](../elixir/SKILL.md), [`php`](../php/SKILL.md) or [`typescript`](../typescript/SKILL.md); the CI pipeline that runs your Ruby tests to [`github-actions`](../github-actions/SKILL.md) — this skill writes the tests, not the workflow. Targets **Ruby 4.0** (released 2025-12-25) on **3.4** semantics: Prism is the default parser, string literals warn on mutation without a magic comment, `it` is an implicit block param, and `Set` is now a core class. ## Mental model …
Read the whole file at its exact version.
How to install
mdr add ericrisco/rsc-harness/ruby@sha256:97ffa368b6a67c75The line at the top of this page pins the label git:20260729.baa11e7, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_y66ly4ripczg47mc)
3 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 2 versions of this file, between Jun 2, 2026 and Jul 29, 2026, about one every 57 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20260729.baa11e7 latest | 2026-07-29 | baa11e7 | 12,763 B | A | view · diff |
| git:20260602.c9dc7fb | 2026-06-02 | c9dc7fb | 14,033 B | A | view |
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (12763 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
ericrisco/rsc-harness · 505 stars · license MIT · pushed 2026-11-04 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_y66ly4ripczg47mc GET https://markdownregistry.com/api/v1/resolve?ref=ericrisco/rsc-harness/ruby GET https://markdownregistry.com/api/v1/blob/97ffa368b6a67c7565691c2d3e4ffc7bbe3d0d9df60a62a60465ef5ec2f63031
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.
More from ericrisco/rsc-harness
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