diff --git a/packages/client/src/i18n/index.ts b/packages/client/src/i18n/index.ts
index 78c4e6f..bb359eb 100644
--- a/packages/client/src/i18n/index.ts
+++ b/packages/client/src/i18n/index.ts
@@ -1,12 +1,5 @@
 import { createI18n } from 'vue-i18n'
-import en from './locales/en'
-import zh from './locales/zh'
-import ja from './locales/ja'
-import ko from './locales/ko'
-import fr from './locales/fr'
-import es from './locales/es'
-import de from './locales/de'
-import pt from './locales/pt'
+import { messages } from './messages'
 
 const saved = localStorage.getItem('hermes_locale')
 const detected = navigator.language.slice(0, 2)
@@ -28,5 +21,5 @@ export const i18n = createI18n({
   legacy: false,
   locale: resolveLocale(saved, detected),
   fallbackLocale: 'en',
-  messages: { en, zh, ja, ko, fr, es, de, pt },
+  messages,
 })
diff --git a/packages/client/src/i18n/locales/de.ts b/packages/client/src/i18n/locales/de.ts
index a6f6fb4..a011e98 100644
--- a/packages/client/src/i18n/locales/de.ts
+++ b/packages/client/src/i18n/locales/de.ts
@@ -85,6 +85,7 @@ export default {
     updateSuccess: 'Aktualisierung abgeschlossen, bitte Server neu starten',
     updateFailed: 'Aktualisierung fehlgeschlagen',
     logout: 'Abmelden',
+    nodeVersionWarning: 'Node.js v{version} erkannt. Bitte aktualisieren Sie auf Version 23 oder neuer.',
     changelog: 'Anderungsprotokoll',
     noChangelog: 'Kein Anderungsprotokoll verfugbar',
   },
@@ -584,5 +585,6 @@ export default {
     unsupportedBackend: 'Aktuelles Terminal-Backend unterstutzt keine Datei-Downloads',
     invalidPath: 'Ungultiger Dateipfad',
     download: 'Herunterladen',
+    downloadFile: 'Datei herunterladen',
   },
 }
diff --git a/packages/client/src/i18n/locales/en.ts b/packages/client/src/i18n/locales/en.ts
index 6f47da0..72702ba 100644
--- a/packages/client/src/i18n/locales/en.ts
+++ b/packages/client/src/i18n/locales/en.ts
@@ -97,6 +97,7 @@ export default {
     updateSuccess: 'Update complete, please restart the server',
     updateFailed: 'Update failed',
     logout: 'Sign Out',
+    nodeVersionWarning: 'Detected Node.js v{version}. Please upgrade to version 23 or later.',
     changelog: 'Changelog',
     noChangelog: 'No changelog available',
   },
@@ -609,6 +610,7 @@ export default {
     unsupportedBackend: 'Current terminal backend does not support file download',
     invalidPath: 'Invalid file path',
     download: 'Download',
+    downloadFile: 'Download file',
   },
 
   // Changelog
diff --git a/packages/client/src/i18n/locales/es.ts b/packages/client/src/i18n/locales/es.ts
index 9721c81..ab255d0 100644
--- a/packages/client/src/i18n/locales/es.ts
+++ b/packages/client/src/i18n/locales/es.ts
@@ -85,6 +85,7 @@ export default {
     updateSuccess: 'Actualizacion completa, por favor reinicia el servidor',
     updateFailed: 'Error al actualizar',
     logout: 'Cerrar sesion',
+    nodeVersionWarning: 'Se detecto Node.js v{version}. Actualiza a la version 23 o posterior.',
     changelog: 'Registro de cambios',
     noChangelog: 'No hay registro de cambios',
   },
@@ -584,5 +585,6 @@ export default {
     unsupportedBackend: 'El backend del terminal actual no admite la descarga de archivos',
     invalidPath: 'Ruta de archivo invalida',
     download: 'Descargar',
+    downloadFile: 'Descargar archivo',
   },
 }
diff --git a/packages/client/src/i18n/locales/fr.ts b/packages/client/src/i18n/locales/fr.ts
index 7b300a2..56dcc0e 100644
--- a/packages/client/src/i18n/locales/fr.ts
+++ b/packages/client/src/i18n/locales/fr.ts
@@ -85,6 +85,7 @@ export default {
     updateSuccess: 'Mise a jour terminee, veuillez redemarrer le serveur',
     updateFailed: 'Echec de la mise a jour',
     logout: 'Deconnexion',
+    nodeVersionWarning: 'Node.js v{version} detecte. Veuillez passer a la version 23 ou ulterieure.',
     changelog: 'Journal des modifications',
     noChangelog: 'Aucun journal disponible',
   },
@@ -584,5 +585,6 @@ export default {
     unsupportedBackend: 'Le backend de terminal actuel ne prend pas en charge le telechargement de fichiers',
     invalidPath: 'Chemin de fichier invalide',
     download: 'Telecharger',
+    downloadFile: 'Telecharger le fichier',
   },
 }
diff --git a/packages/client/src/i18n/locales/ja.ts b/packages/client/src/i18n/locales/ja.ts
index 5acd0d2..6965b91 100644
--- a/packages/client/src/i18n/locales/ja.ts
+++ b/packages/client/src/i18n/locales/ja.ts
@@ -85,6 +85,7 @@ export default {
     updateSuccess: '更新が完了しました。サーバーを再起動してください',
     updateFailed: '更新に失敗しました',
     logout: 'ログアウト',
+    nodeVersionWarning: 'Node.js v{version} が検出されました。バージョン23以降にアップグレードしてください。',
     changelog: '更新履歴',
     noChangelog: '更新履歴はありません',
   },
@@ -584,5 +585,6 @@ export default {
     unsupportedBackend: '現在のターミナルバックエンドはファイルのダウンロードに対応していません',
     invalidPath: '無効なファイルパス',
     download: 'ダウンロード',
+    downloadFile: 'ファイルをダウンロード',
   },
 }
diff --git a/packages/client/src/i18n/locales/ko.ts b/packages/client/src/i18n/locales/ko.ts
index 440e8b8..d3d2141 100644
--- a/packages/client/src/i18n/locales/ko.ts
+++ b/packages/client/src/i18n/locales/ko.ts
@@ -85,6 +85,7 @@ export default {
     updateSuccess: '업데이트 완료, 서버를 재시작해 주세요',
     updateFailed: '업데이트 실패',
     logout: '로그아웃',
+    nodeVersionWarning: 'Node.js v{version}이 감지되었습니다. 버전 23 이상으로 업그레이드하세요.',
     changelog: '변경 이력',
     noChangelog: '변경 이력이 없습니다',
   },
@@ -584,5 +585,6 @@ export default {
     unsupportedBackend: '현재 터미널 백엔드는 파일 다운로드를 지원하지 않습니다',
     invalidPath: '잘못된 파일 경로',
     download: '다운로드',
+    downloadFile: '파일 다운로드',
   },
 }
diff --git a/packages/client/src/i18n/locales/pt.ts b/packages/client/src/i18n/locales/pt.ts
index a83424b..faa3905 100644
--- a/packages/client/src/i18n/locales/pt.ts
+++ b/packages/client/src/i18n/locales/pt.ts
@@ -85,6 +85,7 @@ export default {
     updateSuccess: 'Atualizacao concluida, por favor reinicie o servidor',
     updateFailed: 'Falha na atualizacao',
     logout: 'Sair',
+    nodeVersionWarning: 'Node.js v{version} detectado. Atualize para a versao 23 ou posterior.',
     changelog: 'Registro de alteracoes',
     noChangelog: 'Nenhum registro disponivel',
   },
@@ -584,5 +585,6 @@ export default {
     unsupportedBackend: 'O backend de terminal atual nao suporta download de arquivos',
     invalidPath: 'Caminho de arquivo invalido',
     download: 'Baixar',
+    downloadFile: 'Baixar arquivo',
   },
 }
diff --git a/packages/client/src/i18n/locales/zh.ts b/packages/client/src/i18n/locales/zh.ts
index d1ea8bc..9dcadc5 100644
--- a/packages/client/src/i18n/locales/zh.ts
+++ b/packages/client/src/i18n/locales/zh.ts
@@ -612,6 +612,7 @@ export default {
     unsupportedBackend: '当前 terminal backend 暂不支持文件下载',
     invalidPath: '无效的文件路径',
     download: '下载',
+    downloadFile: '下载文件',
   },
 
   // 更新日志
diff --git a/packages/client/src/i18n/messages.ts b/packages/client/src/i18n/messages.ts
new file mode 100644
index 0000000..3ef7317
--- /dev/null
+++ b/packages/client/src/i18n/messages.ts
@@ -0,0 +1,50 @@
+import de from './locales/de'
+import en from './locales/en'
+import es from './locales/es'
+import fr from './locales/fr'
+import ja from './locales/ja'
+import ko from './locales/ko'
+import pt from './locales/pt'
+import zh from './locales/zh'
+
+export type LocaleMessages = Record<string, unknown>
+
+export const rawMessages = {
+  en,
+  zh,
+  ja,
+  ko,
+  fr,
+  es,
+  de,
+  pt,
+} satisfies Record<string, LocaleMessages>
+
+function isPlainObject(value: unknown): value is LocaleMessages {
+  return !!value && typeof value === 'object' && !Array.isArray(value)
+}
+
+export function mergeMessagesWithFallback(
+  fallback: LocaleMessages,
+  locale: LocaleMessages,
+): LocaleMessages {
+  const merged: LocaleMessages = { ...fallback }
+
+  for (const [key, value] of Object.entries(locale)) {
+    const fallbackValue = fallback[key]
+    merged[key] = isPlainObject(fallbackValue) && isPlainObject(value)
+      ? mergeMessagesWithFallback(fallbackValue, value)
+      : value
+  }
+
+  return merged
+}
+
+export const messages = Object.fromEntries(
+  Object.entries(rawMessages).map(([locale, localeMessages]) => [
+    locale,
+    locale === 'en'
+      ? localeMessages
+      : mergeMessagesWithFallback(en, localeMessages),
+  ]),
+) as typeof rawMessages
diff --git a/tests/client/i18n-coverage.test.ts b/tests/client/i18n-coverage.test.ts
new file mode 100644
index 0000000..0cd586a
--- /dev/null
+++ b/tests/client/i18n-coverage.test.ts
@@ -0,0 +1,72 @@
+import { describe, expect, it } from 'vitest'
+import { readdirSync, readFileSync } from 'fs'
+import { join, relative } from 'path'
+
+import { changelog } from '@/data/changelog'
+import { messages, rawMessages } from '@/i18n/messages'
+
+const SOURCE_ROOT = join(process.cwd(), 'packages/client/src')
+
+function walkFiles(dir: string, files: string[] = []): string[] {
+  for (const entry of readdirSync(dir, { withFileTypes: true })) {
+    const path = join(dir, entry.name)
+    if (entry.isDirectory()) {
+      walkFiles(path, files)
+    } else if (/\.(ts|vue)$/.test(entry.name) && !path.includes('/i18n/locales/')) {
+      files.push(path)
+    }
+  }
+  return files
+}
+
+function collectLiteralTranslationKeys(): string[] {
+  const keys = new Set<string>()
+  const translationCall = /(?:\b|\$)t\(\s*['"]([^'"]+)['"]/g
+
+  for (const file of walkFiles(SOURCE_ROOT)) {
+    const source = readFileSync(file, 'utf8')
+    for (const match of source.matchAll(translationCall)) {
+      keys.add(match[1])
+    }
+  }
+
+  for (const entry of changelog) {
+    for (const change of entry.changes) {
+      keys.add(change)
+    }
+  }
+
+  return [...keys].sort()
+}
+
+function hasPath(messages: Record<string, unknown>, key: string): boolean {
+  let current: unknown = messages
+  for (const part of key.split('.')) {
+    if (!current || typeof current !== 'object' || !(part in current)) return false
+    current = (current as Record<string, unknown>)[part]
+  }
+  return typeof current !== 'undefined'
+}
+
+describe('i18n locale coverage', () => {
+  it('defines every statically referenced translation key in the English source locale', () => {
+    const missing = collectLiteralTranslationKeys().filter((key) => !hasPath(rawMessages.en, key))
+
+    expect(missing).toEqual([])
+  })
+
+  it('defines every statically referenced translation key in effective runtime messages', () => {
+    const requiredKeys = collectLiteralTranslationKeys()
+    const missing = Object.entries(messages).flatMap(([locale, localeMessages]) =>
+      requiredKeys
+        .filter((key) => !hasPath(localeMessages, key))
+        .map((key) => `${locale}: ${key}`),
+    )
+
+    expect(missing).toEqual([])
+  })
+
+  it('keeps the coverage scanner rooted in client source files', () => {
+    expect(relative(process.cwd(), SOURCE_ROOT)).toBe('packages/client/src')
+  })
+})