A Ruby gem that checks data types while Ruby objects are created and methods are called. It also provides building blocks for structured objects, value objects, enums, collections, and result objects.

Use it when writing Ruby code that needs typed properties, runtime type checks, structured data objects, enums, flags, generic collections, or result-style return values.

It helps catch values of the wrong type during program execution without requiring a separate type-checking tool. It also reduces repeated code for common typed Ruby structures.

literal — Skill for Claude Code and Codex by stevegeek: A Ruby gem that checks data types while Ruby…

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.

agentmods

npx agentmods add skills/stevegeek/claude-ruby-plugins/literal

Any agent

npx skills add stevegeek/claude-ruby-plugins --skill literal

Clone the repo

git clone --depth 1 https://github.com/stevegeek/claude-ruby-plugins

Made for: Claude Code, Codex.

Or install literal, the plugin that ships this one along with the rest of its 1 skill.

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.

README.md

[![agentmods](https://agentmods.dev/badge/skills/stevegeek/claude-ruby-plugins/literal.svg)](https://agentmods.dev/skills/stevegeek/claude-ruby-plugins/literal)

Your own site

<a href="https://agentmods.dev/skills/stevegeek/claude-ruby-plugins/literal"><img src="https://agentmods.dev/badge/skills/stevegeek/claude-ruby-plugins/literal.svg" alt="Measured on agentmods" height="20"></a>

Per session 159 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 1,573 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. Scan, not verified.

Origin original 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.

Model	Per session	Once invoked
Fable 5	$0.00159	$0.01573
Opus 5	$0.00079	$0.00787
Sonnet 5	$0.00032	$0.00315
Haiku 4.5	$0.00016	$0.00157

Measured 3d ago against content hash 8096be9eb250, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

literal 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 3d 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.

plugins/literal/skills/literal/SKILL.md · 96 lines

How it starts

The opening of the file, as written. The whole thing — 96 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Literal

Literal is a runtime type system for Ruby. It checks types when objects are constructed and when methods are called - no separate type checker needed. The library also provides building blocks for structured objects (Struct/Data), value objects, enums, flags, generic collections, and result monads.

The gemspec summary captures it: "Enums, properties, generics, structured objects and runtime type checking."

Repo: https://github.com/joeldrapper/literal
Docs: https://literal.fun
License: MIT, requires Ruby >= 3.1

How to use this skill

This skill is organised around the major user-facing features. The top-level features are listed below. When the user is working on a specific feature, load the matching reference file from references/ for full details. Don't load every reference up-front - they're meant to be consulted as needed.

Core idea: types are anything that responds to `===`

In Literal, a "type" is just anything that returns true/false from ===. That includes:

Plain Ruby classes (String, Integer, MyClass) - via Module#=== (instance check)
Ranges (1..10) - via Range#=== (cover check)
Regexps (/foo/) - via Regexp#=== (match check)
Procs/lambdas - via Proc#=== (call check)
Literal's own type matchers from Literal::Types (all prefixed with _)
Any object you define with ===

This is why every Literal API that accepts a "type" can also accept a primitive class or range.

Top-level features (and which reference to load)

Feature	What it is	Reference
Type matchers (`_Array`, `_Union`, `_Map`, `_Nilable`, `_Constraint`, ...)	The `_*` methods from `Literal::Types` for building runtime types	`references/types.md`
`prop` / `prop?`	Typed properties on any class via `extend Literal::Properties`	`references/properties.md`
`Literal::Struct`	Mutable structured object with `prop` (writers + readers public by default)	`references/struct-and-data.md`
`Literal::Data`	Frozen, immutable structured object with `prop` (reader-only)	`references/struct-and-data.md`
`Literal::Value(...)`	Typed value-object wrapper around a single value (e.g. `UserID = Literal::Value(Integer)`)	`references/value-and-delegator.md`
`Literal::Delegator(...)`	Typed delegator wrapping a value with full method delegation	`references/value-and-delegator.md`
`Literal::Enum(type)`	Closed set of typed members with predicates, indexing, ordering	`references/enum.md`
`Literal::Flags8/16/32/64`	Compact bitfield with named flags (boolean attributes)	`references/flags.md`
`Literal::Array/Set/Hash/Tuple` generics	Type-checked collection wrappers (`Literal::Array(String)`)	`references/collections.md`
`Literal::Result(success_t, failure_t)`	Result monad with `Success`/`Failure`, `try`, `and_then`, `also`, `handle`	`references/result.md`
`Literal::SerializationContext` + serializers	JSON-style serialize/deserialize driven by Literal types	`references/serialization.md`
`Literal.check`, `Literal.subtype?`, error messages	Programmatic type checking and subtype predicates	`references/runtime-checks.md`
Rails integration	`ActiveModel::Type` wrappers for enums and flags, `ActiveRecord::Relation(Model)` matcher	`references/rails.md`

Read the full file on GitHub · 96 lines

Files

What ships with it

12 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.

3d ago First seen · 96 lines · 159 tokens per session scan A 8096be9eb250

Subscribe to this mod's changes

literal is a skill published in the GitHub repository stevegeek/claude-ruby-plugins (19 stars, last pushed 4mo ago), licensed Unlicense. It adds 159 tokens to every session and 1,573 once invoked, about $0.0008 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 2026-08-30.

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