I18N

i18n Skill

Standards and workflow for internationalization. All user-visible text must use i18n.

Announce at start: "I'm using i18n skill to ensure proper internationalization."

IMPORTANT: Read Config First

Before doing any i18n work, always read src/common/config/i18n-config.json to get the current list of supported languages and modules. Never assume a fixed number - languages and modules may have been added or removed since this skill was written.

cat src/common/config/i18n-config.json

This file is the single source of truth. All scripts, runtime code, and this workflow depend on it.

File Structure

src/common/config/i18n-config.json              # Single source of truth: languages, modules
src/renderer/i18n/
├── index.ts                             # i18next configuration
├── i18n-keys.d.ts                       # AUTO-GENERATED - do not edit manually
└── locales/
    ├── <lang>/                          # One directory per language in i18n-config.json
    │   ├── index.ts                     # Barrel import for all modules
    │   ├── common.json                  # One JSON per module in i18n-config.json
    │   ├── conversation.json
    │   └── ...
    └── ...

Key Facts

• Reference language: defined by referenceLanguage in i18n-config.json (currently en-US)
• Supported languages: defined by supportedLanguages array - read the file to get the current list
• Modules: defined by modules array - read the file to get the current list

Key Structure

Keys use namespaced dot notation in code: t('module.key') or t('module.nested.key').

Inside each module JSON file, keys can be flat or nested:

// common.json - flat keys
{
  "send": "Send",
  "cancel": "Cancel",
  "copySuccess": "Copied"
}

// cron.json - nested keys
{
  "scheduledTasks": "Scheduled Tasks",
  "status": {
    "active": "Active",
    "paused": "Paused"
  }
}

In code:

t('common.send'); // flat key in common.json
t('cron.status.active'); // nested key in cron.json

Key Naming Rules

• Use camelCase for key names: copySuccess, scheduledTasks
• Group related keys with nesting: status.active, actions.pause
• Reusable text goes in common.json: save, cancel, delete, confirm, etc.
• Feature-specific text goes in the corresponding module

Common Suffixes

Adding New Text - Workflow

Step 1: Read src/common/config/i18n-config.json

Get the current language list and module list. Do not skip this step.

Step 2: Check Existing Keys

Before adding a new key, search for similar existing keys:

grep -r "keyword" src/renderer/i18n/locales/en-US/

Reuse common.* keys when possible.

Step 3: Choose the Right Module

Match the module to the feature area. If no module fits, consider whether a new module is needed (see "Adding a New Module" below).

Step 4: Add to ALL Locale Directories

CRITICAL: Every new key must be added to every locale in supportedLanguages. Use this checklist for each key:

• en-US/<module>.json - reference language (added in Step 3)
• zh-CN/<module>.json - added
• zh-TW/<module>.json - added
• Any other language listed in src/common/config/i18n-config.json → supportedLanguages - added

A key missing from even one locale will cause node scripts/check-i18n.js to fail in CI.

Step 5: Use in Component

import { useTranslation } from 'react-i18next';

function MyComponent() {
  const { t } = useTranslation();
  return <button>{t('common.save')}</button>;
}

Step 6: Regenerate Types and Validate

Run these two commands in order - both must pass before committing:

bun run i18n:types          # Step A: regenerate i18n-keys.d.ts from reference locale
node scripts/check-i18n.js  # Step B: validate structure, keys, and type sync

• i18n:types must be run before check-i18n.js - the check validates the generated file
• If check-i18n.js exits with errors (❌), fix them before proceeding
• If check-i18n.js exits with warnings only (⚠️), review but may proceed
• Never commit with a stale i18n-keys.d.ts

Adding a New Module

1. Add module name to src/common/config/i18n-config.json → modules array
2. Create <module>.json in every locale directory (read supportedLanguages to know which)
3. Add import + export in each locale's index.ts
4. Run bun run i18n:types to regenerate type definitions
5. Run node scripts/check-i18n.js to validate

Hardcoded String Detection

Prohibited Patterns

Never use hardcoded Chinese/English text in JSX:

// Bad
<span>重命名</span>
<span>Delete</span>
{name || '新对话'}

// Good
<span>{t('common.rename')}</span>
<span>{t('common.delete')}</span>
{name || t('conversation.newConversation')}

Exceptions

• Code comments (any language OK)
• console.log() / debug output
• Internal string constants not shown to users

Interpolation

Variables

{
  "taskCount": "{{count}} task(s)",
  "greeting": "Hello, {{name}}!"
}

t('cron.taskCount', { count: 5 });

HTML in Translations

Use Trans component for complex markup:

import { Trans } from 'react-i18next';

<Trans i18nKey='cron.countdown'>
  Task <strong>{{ taskName }}</strong> in <span>{{ countdown }}</span>
</Trans>;

zh-TW Maintenance

Most terms can be auto-converted from zh-CN, but some need manual review:

Quick Checklist

Before submitting code with new text:

• Read src/common/config/i18n-config.json to get current languages and modules
• All user-visible text uses t() function
• New keys added to every locale directory in supportedLanguages
• No hardcoded Chinese/English in JSX
• zh-TW reviewed for term differences
• bun run i18n:types ran first (regenerates i18n-keys.d.ts)
• node scripts/check-i18n.js passed after types regenerated (no errors)

Common Mistakes