A tutorial-style introduction to a Ruby, Rails, and Grape development add-on and its commands, specialist agents, skills, and working rules.

Use it to learn the available workflow, try common commands, and understand installation permissions and project setup.

It gives newcomers a starting point when they do not yet know how the add-on organizes planning, coding, verification, and review.

rb:intro — Skill for Claude Code by slbug

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 slbug/claude-ruby-grape-rails --skill intro

Clone the repo

git clone --depth 1 https://github.com/slbug/claude-ruby-grape-rails

Made for: Claude Code.

Or install ruby-grape-rails, the plugin that ships this one along with the rest of its 52 skills, 19 agents, 17 hooks.

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/slbug/claude-ruby-grape-rails/intro.svg)](https://agentmods.dev/skills/slbug/claude-ruby-grape-rails/intro)

Your own site

<a href="https://agentmods.dev/skills/slbug/claude-ruby-grape-rails/intro"><img src="https://agentmods.dev/badge/skills/slbug/claude-ruby-grape-rails/intro.svg" alt="Measured on agentmods" height="20"></a>

Per session 42 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 769 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	$0.00042	$0.00769
Opus 5	$0.00021	$0.00385
Sonnet 5	$0.00008	$0.00154
Haiku 4.5	$0.00004	$0.00077

Measured 7d ago against content hash a03504465dfb, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

rb:intro 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 7d 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/ruby-grape-rails/skills/intro/SKILL.md · 73 lines

How it starts

The opening of the file, as written. The whole thing — 73 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Intro

Interactive introduction to the Ruby/Rails/Grape plugin for new users.

Quick Start

Plan a feature: /rb:plan Add user authentication with Devise
Work the plan: /rb:work .claude/plans/user-authentication/plan.md
Verify & Review: /rb:verify then /rb:review

What You Get

19 specialist agents: ActiveRecord, Hotwire, security, Sidekiq, provenance experts
52 skills: Commands for every phase of development
22 Iron Laws: Non-negotiable rules enforced automatically

Installation Notes

Marketplace Install (Important)

When installing from the Claude Code marketplace, the plugin's specialist agents will prompt for permissions on first use. This is a security restriction — plugin agents follow your session permission policy, so project-level permissions.allow rules are the normal fix.

Workarounds:

Add permissions to your project's .claude/settings.json:
- Command rules: Bash(bundle *), Bash(rails *), Bash(rake *), Bash(mkdir -p **/.claude/**), Bash(*/bin/manifest-update *), Read(*), Grep(*)
- Recursive Edit rules for plugin artifact namespaces (Edit(path) covers the Write tool; scoped Write(path) rules emit a startup warning and are not consulted by the file-permission check): Edit(**/.claude/plans/**), Edit(**/.claude/reviews/**), Edit(**/.claude/audit/**), Edit(**/.claude/research/**), Edit(**/.claude/solutions/**), Edit(**/.claude/skill-metrics/**), Edit(**/.claude/investigations/**)
Run /update-config to apply the recommended Edit allowlist without hand-editing
Run /rb:permissions to generate a narrower project allowlist from recent usage
Use --plugin-dir for local development while iterating on the plugin itself
Set CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS=1 in your shell. Enables SendMessage so spawn-fanout skills can resume agents that paused at maxTurns. Without it, paused agents become coverage gaps.

Read the full file on GitHub · 73 lines

Files

What ships with it

1 file 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.

references/tutorial-content.md 23 KB

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.

7d ago First seen · 73 lines · 42 tokens per session scan A a03504465dfb

Subscribe to this mod's changes

rb:intro is a skill published in the GitHub repository slbug/claude-ruby-grape-rails (7 stars, last pushed 2d ago), licensed MIT. It adds 42 tokens to every session and 769 once invoked, about $0.0002 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.

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