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."

File Structure

src/renderer/i18n/
├── index.ts              # i18next configuration
└── locales/
    ├── en-US.json        # English (primary)
    ├── zh-CN.json        # Simplified Chinese
    ├── zh-TW.json        # Traditional Chinese
    ├── ja-JP.json        # Japanese
    └── ko-KR.json        # Korean

Key Naming Convention

IMPORTANT: New i18n keys MUST use flat dot-notation format.

Format: <module>.<feature>.<detail>

Rules

Examples

✓ cron.form.title
✓ cron.form.namePlaceholder
✓ cron.list.emptyState
✓ settings.llm.apiKeyRequired

✗ cronFormTitle           (missing dots)
✗ CRON.FORM.TITLE         (wrong case)

Flat vs Nested Structure

// ✅ GOOD - flat structure (use for NEW keys)
{
  "cron.form.title": "Create Scheduled Task",
  "cron.form.nameLabel": "Task Name",
  "cron.list.empty": "No scheduled tasks"
}

// ❌ AVOID - nested structure (legacy only, do not add new)
{
  "cron": {
    "form": {
      "title": "..."
    }
  }
}

Rationale:

• Flat keys are searchable in codebase (see t('cron.form.title'), search directly)
• Easier to verify sync across locale files
• Avoids deep nesting confusion

Common Suffixes

Shared Keys

Use common.* for reusable text:

{
  "common.save": "Save",
  "common.cancel": "Cancel",
  "common.confirm": "Confirm",
  "common.delete": "Delete",
  "common.loading": "Loading..."
}

Adding New Text Workflow

Step 1: Check Existing Keys

Before adding new key, search for similar existing keys:

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

Step 2: Add to ALL Locale Files

CRITICAL: Must add to all 5 files simultaneously.

# Files to update:
src/renderer/i18n/locales/en-US.json   # English text
src/renderer/i18n/locales/zh-CN.json   # Simplified Chinese
src/renderer/i18n/locales/zh-TW.json   # Traditional Chinese
src/renderer/i18n/locales/ja-JP.json   # Japanese
src/renderer/i18n/locales/ko-KR.json   # Korean

Step 3: Use in Component

import { useTranslation } from 'react-i18next';

function MyComponent() {
  const { t } = useTranslation();

  return <button>{t('module.feature.action')}</button>;
}

Step 4: Verify Sync

After adding, verify all files have the new keys.

Sync Checking

Before Commit

Always verify key sync across all locale files:

# Quick check - compare line counts (rough indicator)
wc -l src/renderer/i18n/locales/*.json

# Check for flat keys diff between en-US and zh-CN
diff <(grep -oE '"[a-zA-Z0-9_.]+":' src/renderer/i18n/locales/en-US.json | sort -u) \
     <(grep -oE '"[a-zA-Z0-9_.]+":' src/renderer/i18n/locales/zh-CN.json | sort -u)

Fix Sync Issues

If keys are out of sync:

1. Identify missing keys from diff output
2. Add missing keys to appropriate files
3. Re-run diff to verify

Hardcoded String Detection

Prohibited Patterns

Never use hardcoded Chinese/English text in JSX:

// ❌ BAD
<span>重命名</span>
<span>Delete</span>
<button title="更多操作">...</button>
{name || '新对话'}

// ✅ GOOD
<span>{t('common.rename')}</span>
<span>{t('common.delete')}</span>
<button title={t('common.moreActions')}>...</button>
{name || t('chat.newConversation')}

Exceptions

Comments and internal logs are allowed:

// This is a comment, Chinese is OK
console.log('Debug info'); // OK for logs

zh-TW Maintenance

Auto-conversion Safe

Most terms can be auto-converted from zh-CN:

• 设置 → 設置
• 删除 → 刪除
• 确认 → 確認

Manual Adjustment Required

Some terms need manual review:

Interpolation

Variables

{
  "greeting": "Hello, {{name}}!",
  "itemCount": "{{count}} items"
}

t('greeting', { name: 'User' });
t('itemCount', { 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>;

Quick Checklist

Before submitting code with new text:

• All user-visible text uses t() function
• New keys use flat module.feature.detail format
• New keys added to ALL 5 locale files
• No hardcoded Chinese/English in JSX
• zh-TW reviewed for term differences
• ja-JP and ko-KR translations added (or marked TODO)

Common Mistakes