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.
git 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/serializers)<a href="https://agentmods.dev/rules/muraaano/cursor-project-rules-on-rails/serializers"><img src="https://agentmods.dev/badge/rules/muraaano/cursor-project-rules-on-rails/serializers.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 | $0.00215 |
| Opus 5 | $0.00000 | $0.00108 |
| Sonnet 5 | $0.00000 | $0.00043 |
| Haiku 4.5 | $0.00000 | $0.00021 |
Grade A, and why
serializers 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 7d 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
Serializerの実装規約
基本方針
- SerializerでAPIレスポンスのフォーマットを定義する
- Serializerは
app/serializersに配置する - Serializerの名前は、扱うリソースの名前に
Serializerを付けたものとする- 例：
UserSerializer
- 例：
- 扱うリソースやcontrollerに応じて、namespaceを分ける
- 例：
Hoge::UserSerializer
- 例：
- ロジックはなるべくSerializerに含めない
- ビジネスロジックはModelに実装する
- 表示ロジックはDecoratorに実装する
- フィールド名はスネークケースで記述する
- OpenAPIスキーマ（openapi.yml）はキャメルケースだが、blueprinter gemが変換する
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.
- 7d ago First seen · 22 lines · 0 tokens per session scan A 2d07351a09a4
serializers 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 215 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.
Other cursor rules, from other repositories
hatch3r-ruby-rails-patterns
Ruby 3.3+ and Rails 8.x conventions covering Hotwire (Turbo + Stimulus), ActiveRecord patterns, Sidekiq jobs, RSpec testing, RuboCop / Standard, and YJIT performance.
workato-connector-sdk
Cursor rule "workato-connector-sdk" from rkawaishi/workato-dev-kit, covering workato connector sdk (connector.rb), file structure, top-level structure of connector.rb, authorization types and required keys for an action.
graftcode-ruby
Mandatory Graftcode architecture rules for building Ruby backend services (plain classes exposed via Graftcode Gateway, not REST). Ruby is a supported gg runtime but has no dedicated Quick Start yet.
skill-rails-api
Padrões DARE para APIs em Ruby on Rails 8 — API mode, ActiveRecord, Solid Queue, Solid Cable, Action Cable, strong parameters, services, serializers (Blueprinter/Alba), Devise/JWT, rack-attack, rswag/grape-swagger.
rails
Rails: thin controllers, service objects, Turbo.
models
Thin AR models — validations, scopes, enums; naming → naming-rails.mdc.