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 skills/maquina-app/rails-claude-code/simplifynpx skills add maquina-app/rails-claude-code --skill simplifygit clone --depth 1 https://github.com/maquina-app/rails-claude-codeWrote 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/skills/maquina-app/rails-claude-code/simplify)<a href="https://agentmods.dev/skills/maquina-app/rails-claude-code/simplify"><img src="https://agentmods.dev/badge/skills/maquina-app/rails-claude-code/simplify.svg" alt="Measured on agentmods" 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 | $0.00123 | $0.03700 |
| Opus 5 | $0.00062 | $0.01850 |
| Sonnet 5 | $0.00025 | $0.00740 |
| Haiku 4.5 | $0.00012 | $0.00370 |
Grade A, and why
simplify 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.
How it starts
The opening of the file, as written. The whole thing — 498 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Rails Simplifier
Simplify and refine Ruby on Rails code to enhance clarity, consistency, and maintainability while preserving exact functionality. Apply 37signals patterns and the One Person Framework philosophy to make Rails code more vanilla without altering its behavior.
Deeper material lives in two references, read them when a refinement needs more than the summaries below:
references/philosophy.md— the why, distilled from the 37signals / Jorge Manrubia writing.references/patterns.md— the how, an implementation catalog of concrete patterns from the Fizzy codebase (routing, controllers, concerns, state records, auth, jobs, testing, caching, POROs).
Guiding Philosophy
Three ideas drive every refinement. For the full treatment — quotes, examples, and the design principles behind them — read references/philosophy.md.
- One Person Framework (DHH, 2021) — a toolkit powerful enough that one developer can build and maintain a whole competitive app. Rails 8 delivers it via Solid Queue/Cache/Cable, built-in auth, Kamal, and Hotwire. The test: can one person understand this codebase in an afternoon? If not, simplify.
- Conceptual Compression (DHH, RailsConf 2018) — simplify a concept so a developer gets 80% of the value with 20% of the effort (ActiveRecord compresses SQL; Hotwire compresses the frontend; concerns compress model organization). Your job: when code expands cognitive load without proportional value, compress it.
- Vanilla Rails is Plenty (Jorge Manrubia, 37signals) — build even complex apps without service objects, interactors, repositories, or command patterns. Rich domain models expose natural, domain-oriented APIs:
# ✅ GOOD: Natural, domain-oriented API (conceptual compression)
recording.incinerate
card.close
# ❌ BAD: Service/procedural style (expands complexity)
Recording::IncinerationService.execute(recording)
CardClosureService.new(card, user).call
"We strongly prefer the first form. It does a better job of hiding complexity, as it doesn't shift the burden of composition to the caller. It feels more natural, like plain English. It feels more Ruby." — Jorge Manrubia
What ships with it
2 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.
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.
- 4d ago First seen · 498 lines · 123 tokens per session scan A a642d48071f0
simplify is a skill published in the GitHub repository maquina-app/rails-claude-code (47 stars, last pushed 19d ago), licensed MIT. It adds 123 tokens to every session and 3,700 once invoked, about $0.0006 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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