diff --git a/Makefile b/Makefile
index b0bc1b99f6..86cdaa1711 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,7 @@
 .PHONY: build build-backend build-frontend test test-backend test-frontend test-frontend-critical
 
 FRONTEND_CRITICAL_VITEST := \
+	src/i18n/__tests__/localeKeyCompleteness.spec.ts \
 	src/api/__tests__/client.spec.ts \
 	src/api/__tests__/tokenRefresh.spec.ts \
 	src/api/__tests__/channelMonitorV2.spec.ts \
diff --git a/frontend/package.json b/frontend/package.json
index 8af7a4668b..ea14f61962 100644
--- a/frontend/package.json
+++ b/frontend/package.json
@@ -5,7 +5,8 @@
   "type": "module",
   "scripts": {
     "dev": "vite",
-    "build": "vue-tsc -b && vite build",
+    "check:i18n": "vitest run src/i18n/__tests__/localeKeyCompleteness.spec.ts",
+    "build": "pnpm run check:i18n && vue-tsc -b && vite build",
     "preview": "vite preview",
     "lint": "eslint . --ext .vue,.js,.jsx,.cjs,.mjs,.ts,.tsx,.cts,.mts --fix",
     "lint:check": "eslint . --ext .vue,.js,.jsx,.cjs,.mjs,.ts,.tsx,.cts,.mts",
diff --git a/frontend/src/components/account/CreateAccountModal.vue b/frontend/src/components/account/CreateAccountModal.vue
index 451ac2a1ef..87af79dd5a 100644
--- a/frontend/src/components/account/CreateAccountModal.vue
+++ b/frontend/src/components/account/CreateAccountModal.vue
@@ -6368,7 +6368,7 @@ const handleOpenAIImportCodexPAT = async (accessToken: string) => {
       extra: withUpstreamRequestIdHeader(extra)
     })
 
-    appStore.showSuccess(t('admin.accounts.messages.accountCreated'))
+    appStore.showSuccess(t('admin.accounts.accountCreated'))
     emit('created')
     handleClose()
   } catch (error: any) {
diff --git a/frontend/src/i18n/__tests__/localeKeyCompleteness.spec.ts b/frontend/src/i18n/__tests__/localeKeyCompleteness.spec.ts
new file mode 100644
index 0000000000..c6a08b8b8d
--- /dev/null
+++ b/frontend/src/i18n/__tests__/localeKeyCompleteness.spec.ts
@@ -0,0 +1,90 @@
+import { describe, expect, it } from 'vitest'
+
+import en from '../locales/en'
+import zh from '../locales/zh'
+
+type LocaleValue = Record<string, unknown>
+
+function flattenLeafKeys(value: unknown, prefix = ''): string[] {
+  if (value === null || typeof value !== 'object' || Array.isArray(value)) {
+    return prefix ? [prefix] : []
+  }
+
+  return Object.entries(value as LocaleValue).flatMap(([key, child]) => {
+    const path = prefix ? `${prefix}.${key}` : key
+    return flattenLeafKeys(child, path)
+  })
+}
+
+function collectStaticSourceKeys(source: string): string[] {
+  const keys = new Set<string>()
+
+  // Covers useI18n().t(), the global $t(), and direct i18n.t() calls in both
+  // TypeScript and Vue script/template source. Dynamic suffixes are checked by
+  // the runtime type of the value and cannot be proven from source text alone.
+  const translationCalls = /(?:\bi18n\.t|\$t|\bt)\s*\(\s*(['"])([^'"\r\n]+)\1/g
+  for (const match of source.matchAll(translationCalls)) {
+    const key = match[2]
+    if (!key.endsWith('.')) {
+      keys.add(key)
+    }
+  }
+
+  // Router metadata and i18n-t are key references without a t() call.
+  const keyReferences = /(?:keypath|titleKey|descriptionKey)\s*[:=]\s*(['"])([^'"\r\n]+)\1/g
+  for (const match of source.matchAll(keyReferences)) {
+    keys.add(match[2])
+  }
+
+  const i18nTKeypaths = /<i18n-t\b[^>]*\bkeypath\s*=\s*(['"])([^'"\r\n]+)\1/gi
+  for (const match of source.matchAll(i18nTKeypaths)) {
+    keys.add(match[2])
+  }
+
+  return [...keys]
+}
+
+function sourceKeys(): string[] {
+  const sourceFiles = import.meta.glob('../../**/*.{ts,vue}', {
+    query: '?raw',
+    import: 'default',
+    eager: true
+  }) as Record<string, string>
+
+  return Object.entries(sourceFiles)
+    .filter(([path]) => !path.includes('/__tests__/') && !/\.(spec|test)\.ts$/.test(path))
+    .flatMap(([, source]) => collectStaticSourceKeys(source))
+}
+
+function missingKeys(usedKeys: string[], availableKeys: Set<string>): string[] {
+  return usedKeys.filter((key) => !availableKeys.has(key)).sort()
+}
+
+describe('locale key completeness', () => {
+  const enKeys = new Set(flattenLeafKeys(en))
+  const zhKeys = new Set(flattenLeafKeys(zh))
+  const usedKeys = [...new Set(sourceKeys())].sort()
+
+  it('keeps English and Chinese locale schemas identical', () => {
+    expect([...enKeys].filter((key) => !zhKeys.has(key)).sort()).toEqual([])
+    expect([...zhKeys].filter((key) => !enKeys.has(key)).sort()).toEqual([])
+  })
+
+  it('contains a non-empty message for every locale leaf', () => {
+    for (const [locale, messages] of Object.entries({ en, zh })) {
+      const emptyKeys = flattenLeafKeys(messages).filter((key) => {
+        let current: unknown = messages
+        for (const segment of key.split('.')) {
+          current = (current as LocaleValue)[segment]
+        }
+        return typeof current !== 'string' || current.trim() === ''
+      })
+      expect(emptyKeys, `${locale} has empty or non-string messages`).toEqual([])
+    }
+  })
+
+  it('contains every statically referenced production key', () => {
+    expect(missingKeys(usedKeys, enKeys), 'English locale is missing referenced keys').toEqual([])
+    expect(missingKeys(usedKeys, zhKeys), 'Chinese locale is missing referenced keys').toEqual([])
+  })
+})
diff --git a/frontend/src/i18n/locales/en/admin/accounts.ts b/frontend/src/i18n/locales/en/admin/accounts.ts
index 601accc20d..fb7a81a330 100644
--- a/frontend/src/i18n/locales/en/admin/accounts.ts
+++ b/frontend/src/i18n/locales/en/admin/accounts.ts
@@ -748,6 +748,8 @@ export default {
       modelRestriction: 'Model Restriction (Optional)',
       modelWhitelist: 'Model Whitelist',
       modelMapping: 'Model Mapping',
+      fromModel: 'Request model',
+      toModel: 'Target model',
       selectAllowedModels: 'Select allowed models. Leave empty to support all models.',
       mapRequestModels:
         'Map request models to actual models. Left is the requested model, right is the actual model sent to API.',
diff --git a/frontend/src/i18n/locales/en/admin/channels.ts b/frontend/src/i18n/locales/en/admin/channels.ts
index ff8648cdf2..280597f7dc 100644
--- a/frontend/src/i18n/locales/en/admin/channels.ts
+++ b/frontend/src/i18n/locales/en/admin/channels.ts
@@ -64,6 +64,8 @@ export default {
       updateError: 'Failed to update channel',
       deleteError: 'Failed to delete channel',
       nameRequired: 'Please enter a channel name',
+      noGroupsSelected: 'Select at least one group for {platform}',
+      emptyModelsInPricing: 'Add at least one model to the {platform} pricing rule',
       duplicateModels: 'Model "{0}" appears in multiple pricing entries',
       modelConflict: "Model patterns '{model1}' and '{model2}' conflict: overlapping match range. Model names are matched case-insensitively, so an existing entry already covers all case variants — no need to add the variant separately.",
       mappingConflict: "Mapping source patterns '{model1}' and '{model2}' conflict: overlapping match range. Source patterns are matched case-insensitively, so an existing entry already covers all case variants.",
diff --git a/frontend/src/i18n/locales/en/admin/ops.ts b/frontend/src/i18n/locales/en/admin/ops.ts
index 4bb48c64da..46cd922b6b 100644
--- a/frontend/src/i18n/locales/en/admin/ops.ts
+++ b/frontend/src/i18n/locales/en/admin/ops.ts
@@ -579,6 +579,16 @@ export default {
         alertTitle: 'Alert Evaluator',
         groupAvailabilityTitle: 'Group Availability Monitor',
         evalIntervalSeconds: 'Evaluation Interval (seconds)',
+        metricThresholds: 'Metric Thresholds',
+        metricThresholdsHint: 'Configure alert thresholds for metrics, values exceeding thresholds will be displayed in red',
+        slaMinPercent: 'SLA Minimum Percentage',
+        slaMinPercentHint: 'SLA below this value will be displayed in red (default: 99.5%)',
+        ttftP99MaxMs: 'TTFT P99 Maximum (ms)',
+        ttftP99MaxMsHint: 'TTFT P99 above this value will be displayed in red (default: 500ms)',
+        requestErrorRateMaxPercent: 'Request Error Rate Maximum (%)',
+        requestErrorRateMaxPercentHint: 'Request error rate above this value will be displayed in red (default: 5%)',
+        upstreamErrorRateMaxPercent: 'Upstream Error Rate Maximum (%)',
+        upstreamErrorRateMaxPercentHint: 'Upstream error rate above this value will be displayed in red (default: 5%)',
         silencing: {
           title: 'Alert Silencing (Maintenance Mode)',
           enabled: 'Enable silencing',
diff --git a/frontend/src/i18n/locales/en/admin/overview.ts b/frontend/src/i18n/locales/en/admin/overview.ts
index b0b7ba8e74..bb43695a11 100644
--- a/frontend/src/i18n/locales/en/admin/overview.ts
+++ b/frontend/src/i18n/locales/en/admin/overview.ts
@@ -494,6 +494,7 @@ export default {
       leaveEmptyToKeep: 'Leave empty to keep current password',
       generatePassword: 'Generate random password',
       copyPassword: 'Copy password',
+      passwordCopied: 'Password copied',
       creating: 'Creating...',
       updating: 'Updating...',
       form: {
@@ -829,7 +830,7 @@ export default {
       accountsAvailable: 'Avail:',
       accountsRateLimited: 'Limited:',
       accountsTotal: 'Total:',
-      accountsUnit: '',
+      accountsUnit: 'accounts',
       rateAndAccounts: '{rate}x rate · {count} accounts',
       accountsCount: '{count} accounts',
       rateLabel: 'rate',
@@ -1220,12 +1221,6 @@ export default {
         searchAccountPlaceholder: 'Search accounts...',
         accountsHint: 'Select accounts to prioritize for this model pattern'
       },
-      mcpXml: {
-        title: 'MCP XML Protocol Injection',
-        tooltip: 'When enabled, if the request contains MCP tools, an XML format call protocol prompt will be injected into the system prompt. Disable this to avoid interference with certain clients.',
-        enabled: 'Enabled',
-        disabled: 'Disabled'
-      },
       claudeMaxSimulation: {
         title: 'Claude Max Usage Simulation',
         tooltip:
@@ -1234,6 +1229,12 @@ export default {
         disabled: 'Disabled',
         hint: 'Only token categories in usage billing logs are adjusted. No per-request mapping state is persisted.'
       },
+      mcpXml: {
+        title: 'MCP XML Protocol Injection',
+        tooltip: 'When enabled, if the request contains MCP tools, an XML format call protocol prompt will be injected into the system prompt. Disable this to avoid interference with certain clients.',
+        enabled: 'Enabled',
+        disabled: 'Disabled'
+      },
       supportedScopes: {
         title: 'Supported Model Families',
         tooltip: 'Select the model families this group supports. Unchecked families will not be routed to this group.',
diff --git a/frontend/src/i18n/locales/en/common.ts b/frontend/src/i18n/locales/en/common.ts
index d0afbee551..dffb64e0a3 100644
--- a/frontend/src/i18n/locales/en/common.ts
+++ b/frontend/src/i18n/locales/en/common.ts
@@ -12,6 +12,12 @@ export default {
     delete: 'Delete',
     edit: 'Edit',
     create: 'Create',
+    apply: 'Apply',
+    clear: 'Clear',
+    creating: 'Creating...',
+    required: 'Required',
+    sending: 'Sending...',
+    tryAgain: 'Please try again',
     update: 'Update',
     confirm: 'Confirm',
     reset: 'Reset',
diff --git a/frontend/src/i18n/locales/zh/admin/accounts.ts b/frontend/src/i18n/locales/zh/admin/accounts.ts
index ad5cf05d3c..64f5e96e5f 100644
--- a/frontend/src/i18n/locales/zh/admin/accounts.ts
+++ b/frontend/src/i18n/locales/zh/admin/accounts.ts
@@ -825,6 +825,8 @@ export default {
       modelRestriction: '模型限制（可选）',
       modelWhitelist: '模型白名单',
       modelMapping: '模型映射',
+      fromModel: '请求模型',
+      toModel: '目标模型',
       selectAllowedModels: '选择允许的模型。留空则支持所有模型。',
       mapRequestModels: '将请求模型映射到实际模型。左边是请求的模型，右边是发送到 API 的实际模型。',
       selectedModels: '已选择 {count} 个模型',
diff --git a/frontend/src/i18n/locales/zh/admin/channels.ts b/frontend/src/i18n/locales/zh/admin/channels.ts
index d4a5145676..db3045f9a0 100644
--- a/frontend/src/i18n/locales/zh/admin/channels.ts
+++ b/frontend/src/i18n/locales/zh/admin/channels.ts
@@ -64,6 +64,8 @@ export default {
       updateError: '更新渠道失败',
       deleteError: '删除渠道失败',
       nameRequired: '请输入渠道名称',
+      noGroupsSelected: '请为 {platform} 至少选择一个分组',
+      emptyModelsInPricing: '请为 {platform} 定价规则至少添加一个模型',
       duplicateModels: '模型「{0}」在多个定价条目中重复',
       modelConflict: "模型模式 '{model1}' 和 '{model2}' 冲突：匹配范围重叠。模型名称按大小写不敏感匹配，已有条目已覆盖其所有大小写变体，无需重复添加。",
       mappingConflict: "模型映射源 '{model1}' 和 '{model2}' 冲突：匹配范围重叠。源模式按大小写不敏感匹配，已有条目已覆盖其所有大小写变体。",
diff --git a/frontend/src/i18n/locales/zh/admin/ops.ts b/frontend/src/i18n/locales/zh/admin/ops.ts
index 3e568e1dd7..c95ea7feee 100644
--- a/frontend/src/i18n/locales/zh/admin/ops.ts
+++ b/frontend/src/i18n/locales/zh/admin/ops.ts
@@ -579,6 +579,16 @@ export default {
         alertTitle: '告警评估器',
         groupAvailabilityTitle: '分组可用性监控',
         evalIntervalSeconds: '评估间隔（秒）',
+        metricThresholds: '指标阈值配置',
+        metricThresholdsHint: '配置各项指标的告警阈值，超出阈值时将以红色显示',
+        slaMinPercent: 'SLA 最低百分比',
+        slaMinPercentHint: 'SLA 低于此值时显示为红色（默认：99.5%）',
+        ttftP99MaxMs: 'TTFT P99 最大值（毫秒）',
+        ttftP99MaxMsHint: 'TTFT P99 高于此值时显示为红色（默认：500ms）',
+        requestErrorRateMaxPercent: '请求错误率最大值（%）',
+        requestErrorRateMaxPercentHint: '请求错误率高于此值时显示为红色（默认：5%）',
+        upstreamErrorRateMaxPercent: '上游错误率最大值（%）',
+        upstreamErrorRateMaxPercentHint: '上游错误率高于此值时显示为红色（默认：5%）',
         silencing: {
           title: '告警静默（维护模式）',
           enabled: '启用静默',
diff --git a/frontend/src/i18n/locales/zh/admin/overview.ts b/frontend/src/i18n/locales/zh/admin/overview.ts
index a06abf9784..a9e0fb31f6 100644
--- a/frontend/src/i18n/locales/zh/admin/overview.ts
+++ b/frontend/src/i18n/locales/zh/admin/overview.ts
@@ -494,6 +494,7 @@ export default {
       leaveEmptyToKeep: '留空则保持原密码不变',
       generatePassword: '生成随机密码',
       copyPassword: '复制密码',
+      passwordCopied: '密码已复制',
       creating: '创建中...',
       updating: '更新中...',
       columns: {
@@ -1213,6 +1214,12 @@ export default {
         selectAccounts: '选择账号',
         noAccounts: '此分组暂无账号',
         loadingAccounts: '加载账号中...',
+        removeRule: '删除规则',
+        noRules: '暂无路由规则',
+        noRulesHint: '添加路由规则以将特定模型请求优先路由到指定账号',
+        searchAccountPlaceholder: '搜索账号...',
+        accountsHint: '选择此模型模式优先使用的账号'
+      },
       claudeMaxSimulation: {
         title: 'Claude Max 用量模拟',
         tooltip:
@@ -1220,12 +1227,6 @@ export default {
         enabled: '已启用（模拟 1h 缓存）',
         disabled: '已禁用',
         hint: '仅调整用量计费日志中的 token 类别。不会持久化每个请求的映射状态。'
-      },
-        removeRule: '删除规则',
-        noRules: '暂无路由规则',
-        noRulesHint: '添加路由规则以将特定模型请求优先路由到指定账号',
-        searchAccountPlaceholder: '搜索账号...',
-        accountsHint: '选择此模型模式优先使用的账号'
       },
       mcpXml: {
         title: 'MCP XML 协议注入',
diff --git a/frontend/src/i18n/locales/zh/common.ts b/frontend/src/i18n/locales/zh/common.ts
index c5b2c4002e..2c61d3c7d0 100644
--- a/frontend/src/i18n/locales/zh/common.ts
+++ b/frontend/src/i18n/locales/zh/common.ts
@@ -12,6 +12,12 @@ export default {
     delete: '删除',
     edit: '编辑',
     create: '创建',
+    apply: '应用',
+    clear: '清除',
+    creating: '创建中...',
+    required: '必填',
+    sending: '发送中...',
+    tryAgain: '请重试',
     update: '更新',
     confirm: '确认',
     reset: '重置',