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.
npx agentmods add instructions/ag0os/rails-dev-plugin/claude-mdgit clone --depth 1 https://github.com/ag0os/rails-dev-pluginWhat 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 | $0.02050 | $0.02050 |
| Opus 5 | $0.01025 | $0.01025 |
| Sonnet 5 | $0.00410 | $0.00410 |
| Haiku 4.5 | $0.00205 | $0.00205 |
Grade A, and why
rails-dev-plugin CLAUDE.md 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 2d 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.
How it starts
The opening of the file, as written. The whole thing — 160 lines — stays where its author put it; the contents beside it link to each section on GitHub.
CLAUDE.md
This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
Project Overview
This is a Claude Code plugin that provides specialized agents and portable skills for Rails application development. Agents are lean orchestrators that load domain-specific skills via the skills frontmatter field. Skills are independently usable and exportable to other platforms.
Repository Structure
rails-dev-plugin/
├── .claude-plugin/
│ └── plugin.json # Plugin metadata (name, version, description)
├── agents/ # lean agents (reference skills for knowledge)
│ ├── rails-model.md # skills: [rails-model-patterns]
│ ├── rails-controller.md # skills: [rails-controller-patterns]
│ ├── rails-views.md # skills: [rails-views-patterns]
│ ├── rails-service.md # skills: [rails-service-patterns]
│ ├── rails-jobs.md # skills: [rails-jobs-patterns]
│ ├── rails-test.md # skills: [rails-testing-patterns]
│ ├── rails-hotwire.md # skills: [hotwire-patterns]
│ ├── rails-graphql.md # skills: [rails-graphql-patterns]
│ ├── rails-architect.md # skills: [rails-architecture-patterns]
│ ├── rails-devops.md # skills: [rails-devops-patterns]
│ └── rails-api.md # skills: [rails-api-patterns, rails-controller-patterns]
└── skills/ # portable skills (domain knowledge)
├── rails-model-patterns/ # ActiveRecord, associations, migrations
├── rails-controller-patterns/ # RESTful controllers, routing, params
├── rails-views-patterns/ # ERB, partials, helpers, caching
├── rails-service-patterns/ # Service objects, result pattern, DI
├── rails-jobs-patterns/ # ActiveJob, Sidekiq, idempotency
├── rails-testing-patterns/ # RSpec, Minitest, system tests
├── hotwire-patterns/ # Stimulus, Turbo frames/streams
├── rails-graphql-patterns/ # Schema, mutations, DataLoader
├── rails-architecture-patterns/ # Planning, design decisions, skill directory
├── rails-devops-patterns/ # Docker, CI/CD, monitoring, security
├── rails-api-patterns/ # API controllers, serialization, JWT
├── rails-stack-profiles/ # Architecture axis detection (logic placement, delivery)
├── rails-mailer-patterns/ # Action Mailer, email delivery, previews
├── rails-auth-patterns/ # Authentication (built-in vs Devise)
├── rails-caching-patterns/ # Fragment, low-level, HTTP caching
├── ruby-refactoring/ # Code smells, refactoring patterns
├── ruby-object-design/ # Class vs module, Struct, Data
└── project-conventions/ # Auto-detect project-specific coding conventions
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.
- 2d ago First seen · 160 lines · 2,050 tokens per session scan A 4573a62dbc84
rails-dev-plugin CLAUDE.md is an instructions file published in the GitHub repository ag0os/rails-dev-plugin (5 stars, last pushed 3mo ago), licensed MIT. It adds 2,050 tokens to every session, about $0.0103 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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