rails-expert

rails-expert is an agent for Claude Code from Lua2147/claude-toolkit-catalog. It costs 24 tokens per session (956 once invoked), scanned A, original, no licence file.

A Ruby on Rails development specialist for Rails 7 and newer, including Hotwire, Active Record, Turbo, and Stimulus. Rails is a Ruby framework for building web applications.

In plain words
What is it for?
Use it to create or maintain Rails applications, database-backed models, and Hotwire interfaces.
Why use it?
It helps developers follow Rails conventions when building server-rendered web features and working with application data. It also covers the tools used for interactive page updates.

Agent for Claude Code

Written for Claude Code: a Claude Code subagent (agents/*.md). Also seen: model in frontmatter.

Good fit Use it to create or maintain Rails applications, database-backed models, and Hotwire interfaces.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/lua2147/claude-toolkit-catalog/rails-expert
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.

Clone the repo
git clone --depth 1 https://github.com/Lua2147/claude-toolkit-catalog

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.

agentmods badge for rails-expert

README.md
[![agentmods](https://agentmods.dev/badge/agents/lua2147/claude-toolkit-catalog/rails-expert.svg)](https://agentmods.dev/agents/lua2147/claude-toolkit-catalog/rails-expert)
Your own site
<a href="https://agentmods.dev/agents/lua2147/claude-toolkit-catalog/rails-expert"><img src="https://agentmods.dev/badge/agents/lua2147/claude-toolkit-catalog/rails-expert.svg" alt="Measured on agentmods" height="20"></a>
Per session 24 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 956 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 unknown 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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00024 $0.00956
Opus 5 $0.00012 $0.00478
Sonnet 5 $0.00005 $0.00191
Haiku 4.5 $0.00002 $0.00096

Measured 4d ago against content hash cefae99dffd9, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

rails-expert 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 4d 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.

agents/rails-expert.md · 78 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

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.

  1. 4d ago First seen · 78 lines · 24 tokens per session scan A cefae99dffd9

Subscribe to this mod's changes

rails-expert is an agent published in the GitHub repository Lua2147/claude-toolkit-catalog (2 stars, last pushed 4mo ago), with no licence file. It adds 24 tokens to every session and 956 once invoked, about $0.0001 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 2026-09-03.

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