i18n

i18n is a cursor rule for Cursor from muraaano/cursor-project-rules-on-rails. It costs 0 tokens per session (231 once invoked), scanned A, original, MIT.

A set of Rails rules for translating an application into multiple languages and defining its error messages. Rails is a Ruby web framework, and I18n is its built-in translation system.

In plain words
What is it for?
Use it when adding or reviewing Japanese and other language translations, enum labels, or model validation messages in a Rails project.
Why use it?
It keeps translations and error text in predictable files and formats, so language support is not scattered through the code.

Cursor rule for Cursor

Written for Cursor: installed under .cursor/.

Good fit Use it when adding or reviewing Japanese and other language translations, enum labels, or model validation messages in a Rails project.

Compare 6 cursor rules from other repositories ↓
Install with agentmods
npx agentmods add rules/muraaano/cursor-project-rules-on-rails/i18n
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/muraaano/cursor-project-rules-on-rails

Made for: Cursor.

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 i18n

README.md
[![agentmods](https://agentmods.dev/badge/rules/muraaano/cursor-project-rules-on-rails/i18n/github.svg)](https://agentmods.dev/rules/muraaano/cursor-project-rules-on-rails/i18n)
Your own site
<a href="https://agentmods.dev/rules/muraaano/cursor-project-rules-on-rails/i18n"><img src="https://agentmods.dev/badge/rules/muraaano/cursor-project-rules-on-rails/i18n/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.

agentmods 80×15 button for i18n

Your own site · 80×15
<a href="https://agentmods.dev/rules/muraaano/cursor-project-rules-on-rails/i18n"><img src="https://agentmods.dev/badge/rules/muraaano/cursor-project-rules-on-rails/i18n.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 0 Nothing until a file matches its globs; then the whole rule loads.
When invoked 231 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 original 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 $0.00000 $0.00231
Opus 5 $0.00000 $0.00115
Sonnet 5 $0.00000 $0.00046
Haiku 4.5 $0.00000 $0.00023

Measured 9d ago against content hash c83da5ee76a7, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

i18n 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 9d 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.

.cursor/rules/i18n.mdc · 28 lines

What it actually says

多言語対応規約

基本

  • RailsのI18nを使用して多言語対応を実装する
  • 言語ファイルは config/locales/ 配下に配置する
  • enumの翻訳はenum_helpを使い、{column_name}_i18nで呼び出すこと
    • 例: thing.hoge_type_i18n
  • 翻訳は以下のように ja.enums.{model_name}.{enum_name} の形式で定義する
ja:
  enums:
    thing:
      hoge_type:
          a: エー
          b: ビー

エラーメッセージの定義

  • デフォルトのエラーメッセージは config/locales/defaults/ja.yml に定義する
  • モデル固有のエラーメッセージは config/locales/models/ 配下に配置する
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. 9d ago First seen · 28 lines · 0 tokens per session scan A c83da5ee76a7

Subscribe to this mod's changes

i18n 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 231 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.