Borrowing it
Nothing to install: this file belongs to obie/claude-on-rails. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/obie/claude-on-rails/main/CLAUDE.mdgit clone --depth 1 https://github.com/obie/claude-on-railsWrote 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.
[](https://agentmods.dev/instructions/obie/claude-on-rails/claude-md)<a href="https://agentmods.dev/instructions/obie/claude-on-rails/claude-md"><img src="https://agentmods.dev/badge/instructions/obie/claude-on-rails/claude-md/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.
<a href="https://agentmods.dev/instructions/obie/claude-on-rails/claude-md"><img src="https://agentmods.dev/badge/instructions/obie/claude-on-rails/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00725 | $0.00725 |
| Opus 5 | $0.00362 | $0.00362 |
| Sonnet 5 | $0.00145 | $0.00145 |
| Haiku 4.5 | $0.00072 | $0.00072 |
Grade A, and why
claude-on-rails 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 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.
How it starts
The opening of the file, as written. The whole thing — 60 lines — stays where its author put it; the contents beside it link to each section on GitHub.
ClaudeOnRails Development
Project Overview
ClaudeOnRails is a Ruby gem that leverages claude-swarm to create intelligent AI agent teams for Rails development. It generates swarm configurations that allow developers to describe what they want to build in natural language, and the swarm coordinates implementation across all Rails layers.
Guidelines
1. File References in Claude
- Use
@filepathsyntax for file references, not/file:filepath - File references are the preferred way to include content without duplicating it
2. Never Overwrite User Configuration
- Always check if CLAUDE.md exists before writing to it
- Use file references to include framework content rather than appending
- Store framework-specific content in separate files (e.g.,
.claude-on-rails/context.md)
3. Claude-Swarm Integration
- The default configuration file is
claude-swarm.yml, notswarm.yml - Command is simply
claude-swarm, notclaude-swarm orchestrate - claude-swarm is a dependency, so no need to tell users to install it separately
4. Documentation Clarity
- Clearly distinguish between shell commands and Claude prompts
- Use
>prefix for Claude prompts to avoid confusion with bash commands - Be explicit about where commands should be run vs where prompts should be typed
5. Ruby Gem Best Practices
- Keep development dependencies in Gemfile, not gemspec (RuboCop rule)
- Always run
bundle exec rakebefore committing changes to catch syntax and style issues - Use
bundle exec rake releasefor gem releases (creates tag, pushes to RubyGems) - ...then create GitHub releases separately with
gh release create
6. Generator Best Practices
- Check for directory existence before creating agents
- Make generators idempotent (running multiple times shouldn't duplicate content)
- Provide clear next steps after generation
- Show what will be created during the analysis phase
7. Testing Considerations
- Make sure that user confirms that they have tested changes with a real Rails project before releasing
- Consider different Rails configurations (API-only, full-stack, with/without GraphQL)
- IMPORTANT: This project uses RSpec exclusively for testing. NEVER use Minitest or any other testing framework. Do not add minitest gems, create test/ directories, or write any Minitest-style tests. All tests must be written in RSpec format and placed in the spec/ directory.
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 · 60 lines · 725 tokens per session scan A 6fc427f5473c
claude-on-rails CLAUDE.md is an instructions file published in the GitHub repository obie/claude-on-rails (814 stars, last pushed 11mo ago), licensed MIT. It adds 725 tokens to every session, about $0.0036 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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