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 rules/muraaano/cursor-project-rules-on-rails/modelsgit clone --depth 1 https://github.com/muraaano/cursor-project-rules-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/rules/muraaano/cursor-project-rules-on-rails/models)<a href="https://agentmods.dev/rules/muraaano/cursor-project-rules-on-rails/models"><img src="https://agentmods.dev/badge/rules/muraaano/cursor-project-rules-on-rails/models.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 5.1 | $0.00000 | $0.00433 |
| Opus 5 | $0.00000 | $0.00217 |
| Sonnet 5 | $0.00000 | $0.00087 |
| Haiku 4.5 | $0.00000 | $0.00043 |
Grade A, and why
models 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 5d 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.
What it actually says
Modelの実装規約
基本方針
- アプリケーションのドメインロジックを扱う処理は、Modelに実装する
- Modelは
app/modelsに配置する - ファイル名はクラス名のスネークケースとする
- データベースアクセスするテーブルがある場合は、RailsのActiveRecord(実際にはApplicationRecord)を継承したクラスとする
- テーブルがない場合は、PORO（Pure Old Ruby Object）かイベント型モデルを選択する
- 複数のモデルに関連した一連のイベントをまとめる場合は、イベント型モデルとする
- イベントではない場合は、PORO（特に継承をしないクラス）とする
- validationが不要な場合で、イベント型モデルにする理由がない場合はPOROを採用する。
- I/Fが簡素化でき、メモリなどのコストも低いため。
イベント型モデル
ApplicationEventModelを継承して作成する- クラス名は、イベント名の名詞とし、末尾に
Eventをつける- 例：
MoveEvent
- 例：
- I/FはRailsのApplicationModelに準ずる（https://railsguides.jp/active_model_basics.html）
- 例：
valid?,save
- 例：
validation
- カスタムvalidatorの実装はなるべく控え、既存のvalidator(numericalityなど)を使う
トランザクション
-
データの整合性を保つために、関連するデータの更新は必ずトランザクション内で行う
ApplicationRecord.transaction do # データの更新処理 end
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.
- 5d ago First seen · 42 lines · 0 tokens per session scan A 2f01d6d4edf8
models is a cursor rule published in the GitHub repository muraaano/cursor-project-rules-on-rails (2 stars, last pushed 1y ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 433 tokens. 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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dev-standard
Apache Superset development standards and guidelines for Cursor IDE.
cli-error-handling
CLI command error handling patterns.
prefer-direct-imports-over-module-mocks
Prefer extracting a testable core over vi.mock / vi.resetModules when unit tests need to reach production logic entangled with config, env, or singletons.
control-plane-descriptors
Control plane descriptor and instance implementation patterns.