Welcome back
`, `` - Template literals with user-visible content: `` `Hello ${name}` `` - Alert/toast calls with hardcoded strings: `toast.error("Something failed")` - Error message strings in API handlers returned to the client - Placeholder text: `placeholder="Enter your email"` - Aria labels: `aria-label="Close dialog"` - `alt` text on meaningful images Use shell to scan (the codebase search tools may be slow on large repos): ```bash grep -rn 'placeholder="' src/ --include="*.tsx" --include="*.jsx" | head -30 grep -rn '"en":' src/ --include="*.ts" --include="*.tsx" | head -20 ``` Build a list: file path, line number, string content, whether it has an i18n key already. --- ## Phase 2: Audit translation file completeness For each locale, check that all keys from the base locale (usually `en`) exist: ```bash # Example: compare en.json vs ja.json key counts node -e " const en = require('./public/locales/en/common.json'); const ja = require('./public/locales/ja/common.json'); const missing = Object.keys(en).filter(k => !ja[k]); console.log('Missing in ja:', missing); " ``` Or for next-intl format: ```bash node -e " const en = require('./messages/en.json'); const ja = require('./messages/ja.json'); function findMissing(base, target, path='') { for (const k of Object.keys(base)) { const kp = path ? path+'.'+k : k; if (!(k in target)) console.log('MISSING:', kp); else if (typeof base[k] === 'object') findMissing(base[k], target[k], kp); } } findMissing(en, ja); " ``` --- ## Phase 3: Review translation quality This is the most important phase. For each locale, review every string against the natural-language principles at the top of this skill. ### What to look for in each category **Error messages** — must guide, not blame, and tell the user what to do: ```json // Before "errors.email_invalid": "Invalid email address" // After "errors.email_invalid": "That doesn't look like a valid email — check for typos and try again" ``` **Action buttons** — must describe the outcome, not just label the input: ```json // Before "buttons.submit": "Submit" "buttons.confirm": "OK" // After "buttons.submit": "Save changes" // or whatever the action actually does "buttons.confirm": "Got it" // or the specific action: "Delete account", "Send message" ``` **Empty states** — should explain and invite, not just state the absence: ```json // Before "empty.projects": "No projects" // After "empty.projects": "You haven't created any projects yet. Start one to get going." ``` **Success messages** — should feel warm and confirm the action clearly: ```json // Before "success.saved": "Data saved successfully" // After "success.saved": "Saved!" // or "Your changes are saved" ``` **Loading states** — should be human: ```json // Before "loading.data": "Loading data..." // After "loading.data": "Getting things ready…" // or just omit "Loading" entirely ``` ### Locale-specific tone guidelines | Locale | Tone notes | |--------|-----------| | `en` | Friendly, direct, conversational. Use contractions ("you've", "can't"). No formal passive voice. | | `ja` | Use polite but natural keigo (〜ます/〜です form). Avoid literal translations of English idioms. Use short, clear sentences. Don't overuse katakana loanwords when Japanese alternatives exist. | | `ko` | Polite 합쇼체 or 해요체 depending on the app's audience. Avoid Konglish where natural Korean exists. | | `zh-TW` / `zh-CN` | Traditional vs simplified — do not mix. Natural, not literal. Check that date/number formats are locale-correct. | | `fr` | Formal `vous` for most apps; `tu` only for clearly youth/casual products. Gender agreement must be correct — check nouns. | | `de` | German compounds can get long — check for truncation. Formal `Sie` for business apps. | | `es` | Check for `tú`/`usted`/`vosotros` consistency. Latin American vs Spain variants differ. | | RTL (`ar`, `he`) | Mirror layout. Check that numbers are LTR within RTL text. Verify UI wraps correctly. | --- ## Phase 4: Walk the live app in each locale (Playwright) For each active locale: 1. Navigate to the locale-specific URL or trigger the locale switcher 2. Walk the key flows: onboarding, core feature, error states, empty states, settings 3. Screenshot each screen for visual review ```javascript // Set locale via URL or cookie depending on the app await page.goto('http://localhost:3000/ja'); // or set cookie await browser_snapshot(); // capture the state ``` Look for: - Strings that are still in English (untranslated keys showing as key names like `common.save`) - Text that overflows its container in longer languages (German, Finnish, Russian) - Date/time formatting that doesn't match the locale (30/01/2026 vs Jan 30, 2026 vs 2026年1月30日) - Currency symbols in the wrong position (`$10.00` vs `10,00 €` vs `¥1,000`) - Numbers using the wrong decimal/thousands separator (1,234.56 vs 1.234,56) - Plural forms: English has singular/plural; many languages have more forms --- ## Phase 5: Fix — priority order ### Fix 1: Extract all hardcoded strings For every hardcoded string found in Phase 1, create an i18n key and replace it: ```typescript // Before (react-i18next)Welcome back, {name}!
// After const { t } = useTranslation('common');{t('welcome_back', { name })}
``` ```json // en/common.json "welcome_back": "Welcome back, {{name}}!" // ja/common.json "welcome_back": "おかえりなさい、{{name}}さん！" ``` ### Fix 2: Rewrite poor translations Edit the translation files directly. Prioritise: 1. Error messages that blame or confuse users 2. Empty states that dead-end users 3. Action buttons that say "Submit" or "OK" 4. Any string a native speaker would read and say "that's not how we talk" ### Fix 3: Add missing locale keys For any key missing in a non-English locale, add a natural translation. If you don't have a native speaker for a locale, use a clearly-marked placeholder: ```json "some_key": "[TODO: needs native Japanese review] {{count}} items selected" ``` ### Fix 4: Fix number/date/currency formatting Use the i18n library's format functions rather than manual formatting: ```typescript // react-i18next with i18next-icu or i18next-intervalPlural t('items_count', { count: 5 }) // handles plural forms automatically // Intl API for dates and numbers (framework-agnostic) new Intl.DateTimeFormat(locale, { dateStyle: 'long' }).format(date); new Intl.NumberFormat(locale, { style: 'currency', currency: 'JPY' }).format(1234); ``` --- ## Phase 6: i18n audit report ```markdown ## i18n Audit Report — [App] — [Date] ### Active locales [list with coverage % — keys present / total keys] ### Hardcoded strings found | File | Line | String | Action | |------|------|--------|--------| | src/components/Foo.tsx | 42 | "Save" | Extracted to key `buttons.save` | ### Translation quality issues fixed | Locale | Key | Before | After | Issue type | |--------|-----|--------|-------|-----------| | ja | errors.email_invalid | "無効なメールアドレス" | "メールアドレスが正しくないようです。入力内容をご確認ください。" | Too literal, not helpful | ### Missing keys added [count per locale] ### Formatting fixes [date/number/currency issues found and fixed] ### Still needs native review [keys marked [TODO] that need a human native speaker] ```