---
name: i18n-completeness
description: Comprehensive i18n consistency check with dynamic pattern detection and hardcoded string analysis. Use when working with translations, localization, i18n keys, or when the user mentions translation issues, missing keys, or language support. Auto-triggers on phrases like "check translations", "i18n consistency", "localization issues", or "translation keys".
allowed-tools: Bash(bun run check:i18n*), Read, Edit, Grep, Glob
---

# i18n Consistency Check & Cleanup

Comprehensive i18n analysis tool for the Tetris project supporting 2 languages (Japanese, English).

## Quick Check

```bash
bun run check:i18n
```

## Detection Capabilities

### 🔴 Missing Keys (Critical)
- Keys used in code but not present in translation files
- **Priority**: Critical (causes runtime errors)
- **Impact**: Displays raw translation keys to users
- **Action**: Add missing keys to all translation files immediately

### 📝 Hardcoded Strings (i18n Compliance)
- User-facing strings not using `t()` function
- **Examples**: "AI Replay", "Start AI", "Loading..."
- **Scope**: Production code only (test files excluded)
- **Action**: Convert to translation keys for proper localization

### 🔄 Dynamic Key Patterns (Analysis Required)
- Template literal patterns like `t(\`game.${type}\`)`
- **Analysis**: Validates all possible key combinations exist
- **Action**: Verify all generated keys are defined

### ⚠️ Unused Keys (Optimization)
- Keys present in translation files but not used in code
- **Priority**: Medium (cleanup opportunity)
- **Action**: Remove unnecessary keys to optimize file size

## Workflow

1. **Execute Check**: Run `bun run check:i18n`
2. **Identify Issues**: List Missing/Unused keys
3. **Propose Fixes**: Present specific correction methods
4. **Confirm Execution**: Ask user to approve modifications
5. **Apply Fixes**: Update translation files after approval
6. **Verify**: Re-run check after modifications

## Translation Files

- `src/assets/locales/ja.json` - Japanese translations (default)
- `src/assets/locales/en.json` - English translations

## Safety Measures

- Re-verify usage before key deletion
- Execute consistent operations across all language files
- Validate JSON syntax after modifications
- Confirm no issues with tests and build

## When This Skill Activates

- "Check translations"
- "i18n consistency check"
- "Are all translation keys defined?"
- "Find hardcoded strings"
- "Translation cleanup"
- "Localization issues"
- "Missing translation keys"