What is rails-guides?

A reference guide to Ruby on Rails, a framework for building web applications. It covers Rails features such as database models, routes, controllers, views, background jobs, and security.

Use it to build, review, debug, or explain Rails code, including database queries, migrations, validations, associations, caching, and application configuration.

It gives coding agents reliable Rails-specific guidance instead of making guesses or relying on incomplete general knowledge.

rails-guides — Skill for Claude Code by zarpay

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 zarpay/rails-template --skill rails-guides

Clone the repo

git clone --depth 1 https://github.com/zarpay/rails-template

Made for: Claude Code.

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/zarpay/rails-template/rails-guides/github.svg)](https://agentmods.dev/skills/zarpay/rails-template/rails-guides)

Your own site

<a href="https://agentmods.dev/skills/zarpay/rails-template/rails-guides"><img src="https://agentmods.dev/badge/skills/zarpay/rails-template/rails-guides/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.

Your own site · 80×15

<a href="https://agentmods.dev/skills/zarpay/rails-template/rails-guides"><img src="https://agentmods.dev/badge/skills/zarpay/rails-template/rails-guides.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 56 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 1,038 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 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 5.1	$0.00056	$0.01038
Opus 5	$0.00028	$0.00519
Sonnet 5	$0.00011	$0.00208
Haiku 4.5	$0.00006	$0.00104

Measured 10d ago against content hash e34b2a18bec8, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

rails-guides 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 10d 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.

files/.claude/skills/rails-guides/SKILL.md · 82 lines

How it starts

The opening of the file, as written. The whole thing — 82 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Rails Guides

Official Rails documentation for reference during development.

Topic Map

Getting Started

references/getting_started.md — Rails basics, MVC overview, first app walkthrough
references/command_line.md — rails command, generators, rake tasks
references/configuring.md — Environments, initializers, credentials, database.yml
references/autoloading_and_reloading_constants.md — Zeitwerk, module naming, reload behavior
references/initialization.md — Rails boot sequence, railties, engines

Active Record

references/active_record_basics.md — Models, CRUD, conventions, migrations
references/active_record_querying.md — Finders, scopes, joins, includes, explain
references/active_record_validations.md — Built-in validators, custom validators, errors
references/active_record_callbacks.md — Lifecycle hooks, after_commit, skip_callback
references/association_basics.md — belongs_to, has_many, has_one, HABTM, polymorphic
references/active_record_migrations.md — Schema changes, reversible migrations, db:migrate
references/active_record_encryption.md — Encrypting attributes at rest
references/active_record_composite_primary_keys.md — Multi-column primary keys
references/active_record_multiple_databases.md — Multi-DB setup, sharding, replicas
references/active_record_postgresql.md — PostgreSQL-specific features (hstore, jsonb, arrays)
references/active_model_basics.md — ActiveModel outside ActiveRecord, form objects

Action Controller

references/action_controller_overview.md — Controllers, params, filters, sessions, cookies
references/action_controller_advanced_topics.md — Streaming, live, metal, http auth
references/routing.md — Resources, namespaces, constraints, named routes, URL helpers

Action View

references/action_view_overview.md — Templates, partials, layouts, formats
references/action_view_helpers.md — form_with, link_to, tag, content_tag, asset helpers
references/form_helpers.md — form_with, field helpers, nested forms, uploads
references/layouts_and_rendering.md — render, redirect_to, respond_to, layout inheritance

Read the full file on GitHub · 82 lines

Files

What ships with it

44 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.

10d ago First seen · 82 lines · 56 tokens per session scan A e34b2a18bec8

Subscribe to this mod's changes

rails-guides is a skill published in the GitHub repository zarpay/rails-template (9 stars, last pushed 28d ago), licensed MIT. It adds 56 tokens to every session and 1,038 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 2026-08-31.

Languages Learning and teaching Ruby

rails-guides

Getting it into your agent

Wrote this? Show the measurements

What it costs to keep this loaded

Grade A, and why

Nothing flagged

How it starts

Rails Guides

Topic Map

Getting Started

Active Record

Action Controller

Action View

What ships with it

What this file has done since we first saw it

Other skills, from other repositories

rb:intro

ljg-word

new

course

llvm-learning

ruby-patterns