diff --git a/src/routes/api.js b/src/routes/api.js
index 8fe0676b..4d298716 100644
--- a/src/routes/api.js
+++ b/src/routes/api.js
@@ -38,6 +38,73 @@ function queueRateLimitUpdate(rateLimitInfo, usageSummary, model, context = '')
     })
 }
 
+/**
+ * 判断是否为旧会话（污染的会话）
+ * Claude Code 发送的请求特点：
+ * - messages 数组通常只有 1 个元素
+ * - 历史对话记录嵌套在单个 message 的 content 数组中
+ * - content 数组中包含 <system-reminder> 开头的系统注入内容
+ *
+ * 污染会话的特征：
+ * 1. messages.length > 1
+ * 2. messages.length === 1 但 content 中有多个用户输入
+ * 3. "warmup" 请求：单条简单消息 + 无 tools（真正新会话会带 tools）
+ *
+ * @param {Object} body - 请求体
+ * @returns {boolean} 是否为旧会话
+ */
+function isOldSession(body) {
+  const messages = body?.messages
+  const tools = body?.tools
+
+  if (!messages || messages.length === 0) {
+    return false
+  }
+
+  // 1. 多条消息 = 旧会话
+  if (messages.length > 1) {
+    return true
+  }
+
+  // 2. 单条消息，分析 content
+  const firstMessage = messages[0]
+  const content = firstMessage?.content
+
+  if (!content) {
+    return false
+  }
+
+  // 如果 content 是字符串，只有一条输入，需要检查 tools
+  if (typeof content === 'string') {
+    // 有 tools = 正常新会话，无 tools = 可疑
+    return !tools || tools.length === 0
+  }
+
+  // 如果 content 是数组，统计非 system-reminder 的元素
+  if (Array.isArray(content)) {
+    const userInputs = content.filter((item) => {
+      if (item.type !== 'text') {
+        return false
+      }
+      const text = item.text || ''
+      // 剔除以 <system-reminder> 开头的
+      return !text.trimStart().startsWith('<system-reminder>')
+    })
+
+    // 多个用户输入 = 旧会话
+    if (userInputs.length > 1) {
+      return true
+    }
+
+    // Warmup 检测：单个消息 + 无 tools = 旧会话
+    if (userInputs.length === 1 && (!tools || tools.length === 0)) {
+      return true
+    }
+  }
+
+  return false
+}
+
 // 🔧 共享的消息处理函数
 async function handleMessagesRequest(req, res) {
   try {
@@ -233,19 +300,18 @@ async function handleMessagesRequest(req, res) {
       }
 
       // 🔗 在成功调度后建立会话绑定（仅 claude-official 类型）
-      // claude-official 只接受：1) 新会话(messages.length=1) 2) 已绑定的会话
+      // claude-official 只接受：1) 新会话 2) 已绑定的会话
       if (
         needSessionBinding &&
         originalSessionIdForBinding &&
         accountId &&
         accountType === 'claude-official'
       ) {
-        // 🚫 新会话必须 messages.length === 1
-        const messages = req.body?.messages
-        if (messages && messages.length > 1) {
+        // 🚫 检测旧会话（污染的会话）
+        if (isOldSession(req.body)) {
           const cfg = await claudeRelayConfigService.getConfig()
           logger.warn(
-            `🚫 New session with messages.length > 1 rejected: sessionId=${originalSessionIdForBinding}, messages.length=${messages.length}`
+            `🚫 Old session rejected: sessionId=${originalSessionIdForBinding}, messages.length=${req.body?.messages?.length}, tools.length=${req.body?.tools?.length || 0}, isOldSession=true`
           )
           return res.status(400).json({
             error: {
@@ -684,19 +750,18 @@ async function handleMessagesRequest(req, res) {
       }
 
       // 🔗 在成功调度后建立会话绑定（非流式，仅 claude-official 类型）
-      // claude-official 只接受：1) 新会话(messages.length=1) 2) 已绑定的会话
+      // claude-official 只接受：1) 新会话 2) 已绑定的会话
       if (
         needSessionBindingNonStream &&
         originalSessionIdForBindingNonStream &&
         accountId &&
         accountType === 'claude-official'
       ) {
-        // 🚫 新会话必须 messages.length === 1
-        const messages = req.body?.messages
-        if (messages && messages.length > 1) {
+        // 🚫 检测旧会话（污染的会话）
+        if (isOldSession(req.body)) {
           const cfg = await claudeRelayConfigService.getConfig()
           logger.warn(
-            `🚫 New session with messages.length > 1 rejected (non-stream): sessionId=${originalSessionIdForBindingNonStream}, messages.length=${messages.length}`
+            `🚫 Old session rejected (non-stream): sessionId=${originalSessionIdForBindingNonStream}, messages.length=${req.body?.messages?.length}, tools.length=${req.body?.tools?.length || 0}, isOldSession=true`
           )
           return res.status(400).json({
             error: {
@@ -1157,6 +1222,41 @@ router.post('/v1/messages/count_tokens', authenticateApiKey, async (req, res) =>
     })
   }
 
+  // 🔗 会话绑定验证（与 messages 端点保持一致）
+  const originalSessionId = claudeRelayConfigService.extractOriginalSessionId(req.body)
+  const sessionValidation = await claudeRelayConfigService.validateNewSession(
+    req.body,
+    originalSessionId
+  )
+
+  if (!sessionValidation.valid) {
+    logger.warn(
+      `🚫 Session binding validation failed (count_tokens): ${sessionValidation.code} for session ${originalSessionId}`
+    )
+    return res.status(400).json({
+      error: {
+        type: 'session_binding_error',
+        message: sessionValidation.error
+      }
+    })
+  }
+
+  // 🔗 检测旧会话（污染的会话）- 仅对需要绑定的新会话检查
+  if (sessionValidation.isNewSession && originalSessionId) {
+    if (isOldSession(req.body)) {
+      const cfg = await claudeRelayConfigService.getConfig()
+      logger.warn(
+        `🚫 Old session rejected (count_tokens): sessionId=${originalSessionId}, messages.length=${req.body?.messages?.length}, tools.length=${req.body?.tools?.length || 0}, isOldSession=true`
+      )
+      return res.status(400).json({
+        error: {
+          type: 'session_binding_error',
+          message: cfg.sessionBindingErrorMessage || '你的本地session已污染，请清理后使用。'
+        }
+      })
+    }
+  }
+
   logger.info(`🔢 Processing token count request for key: ${req.apiKey.name}`)
 
   const sessionHash = sessionHelper.generateSessionHash(req.body)
diff --git a/src/services/claudeRelayConfigService.js b/src/services/claudeRelayConfigService.js
index 3b9790ac..5d4c3bd5 100644
--- a/src/services/claudeRelayConfigService.js
+++ b/src/services/claudeRelayConfigService.js
@@ -283,12 +283,13 @@ class ClaudeRelayConfigService {
 
       const account = await accountService.getAccount(accountId)
 
-      if (!account || !account.success || !account.data) {
+      // getAccount() 直接返回账户数据对象或 null，不是 { success, data } 格式
+      if (!account) {
         logger.warn(`Session binding account not found: ${accountId} (${accountType})`)
         return false
       }
 
-      const accountData = account.data
+      const accountData = account
 
       // 检查账户是否激活
       if (accountData.isActive === false || accountData.isActive === 'false') {
diff --git a/web/admin-spa/package-lock.json b/web/admin-spa/package-lock.json
index 9405609e..481df56a 100644
--- a/web/admin-spa/package-lock.json
+++ b/web/admin-spa/package-lock.json
@@ -1157,7 +1157,6 @@
       "resolved": "https://registry.npmmirror.com/@types/lodash-es/-/lodash-es-4.17.12.tgz",
       "integrity": "sha512-0NgftHUcV4v34VhXm8QBSftKVXtbkBG3ViCjs6+eJ5a6y6Mi/jiFGPc1sC7QK+9BFhWrURE3EOggmWaSxL9OzQ==",
       "license": "MIT",
-      "peer": true,
       "dependencies": {
         "@types/lodash": "*"
       }
@@ -1352,7 +1351,6 @@
       "integrity": "sha512-NZyJarBfL7nWwIq+FDL6Zp/yHEhePMNnnJ0y3qfieCrmNvYct8uvtiV41UvlSe6apAfk0fY1FbWx+NwfmpvtTg==",
       "dev": true,
       "license": "MIT",
-      "peer": true,
       "bin": {
         "acorn": "bin/acorn"
       },
@@ -1589,7 +1587,6 @@
         }
       ],
       "license": "MIT",
-      "peer": true,
       "dependencies": {
         "caniuse-lite": "^1.0.30001726",
         "electron-to-chromium": "^1.5.173",
@@ -3063,15 +3060,13 @@
       "version": "4.17.21",
       "resolved": "https://registry.npmmirror.com/lodash/-/lodash-4.17.21.tgz",
       "integrity": "sha512-v2kDEe57lecTulaDIuNTPy3Ry4gLGJ6Z1O3vE1krgXZNrsQ+LFTGHVxVjcXPs17LhbZVGedAJv8XZ1tvj5FvSg==",
-      "license": "MIT",
-      "peer": true
+      "license": "MIT"
     },
     "node_modules/lodash-es": {
       "version": "4.17.21",
       "resolved": "https://registry.npmmirror.com/lodash-es/-/lodash-es-4.17.21.tgz",
       "integrity": "sha512-mKnC+QJ9pWVzv+C4/U3rRsHapFfHvQFoFB92e52xeyGMcX6/OlIl78je1u8vePzYZSkkogMPJ2yjxxsb89cxyw==",
-      "license": "MIT",
-      "peer": true
+      "license": "MIT"
     },
     "node_modules/lodash-unified": {
       "version": "1.0.3",
@@ -3623,7 +3618,6 @@
         }
       ],
       "license": "MIT",
-      "peer": true,
       "dependencies": {
         "nanoid": "^3.3.11",
         "picocolors": "^1.1.1",
@@ -3770,7 +3764,6 @@
       "integrity": "sha512-I7AIg5boAr5R0FFtJ6rCfD+LFsWHp81dolrFD8S79U9tb8Az2nGrJncnMSnys+bpQJfRUzqs9hnA81OAA3hCuQ==",
       "dev": true,
       "license": "MIT",
-      "peer": true,
       "bin": {
         "prettier": "bin/prettier.cjs"
       },
@@ -4035,7 +4028,6 @@
       "integrity": "sha512-33xGNBsDJAkzt0PvninskHlWnTIPgDtTwhg0U38CUoNP/7H6wI2Cz6dUeoNPbjdTdsYTGuiFFASuUOWovH0SyQ==",
       "dev": true,
       "license": "MIT",
-      "peer": true,
       "dependencies": {
         "@types/estree": "1.0.8"
       },
@@ -4533,7 +4525,6 @@
       "integrity": "sha512-5gTmgEY/sqK6gFXLIsQNH19lWb4ebPDLA4SdLP7dsWkIXHWlG66oPuVvXSGFPppYZz8ZDZq0dYYrbHfBCVUb1Q==",
       "dev": true,
       "license": "MIT",
-      "peer": true,
       "engines": {
         "node": ">=12"
       },
@@ -4924,7 +4915,6 @@
       "integrity": "sha512-qO3aKv3HoQC8QKiNSTuUM1l9o/XX3+c+VTgLHbJWHZGeTPVAg2XwazI9UWzoxjIJCGCV2zU60uqMzjeLZuULqA==",
       "dev": true,
       "license": "MIT",
-      "peer": true,
       "dependencies": {
         "esbuild": "^0.21.3",
         "postcss": "^8.4.43",
@@ -5125,7 +5115,6 @@
       "resolved": "https://registry.npmmirror.com/vue/-/vue-3.5.18.tgz",
       "integrity": "sha512-7W4Y4ZbMiQ3SEo+m9lnoNpV9xG7QVMLa+/0RFwwiAVkeYoyGXqWE85jabU4pllJNUzqfLShJ5YLptewhCWUgNA==",
       "license": "MIT",
-      "peer": true,
       "dependencies": {
         "@vue/compiler-dom": "3.5.18",
         "@vue/compiler-sfc": "3.5.18",
diff --git a/web/admin-spa/src/views/SettingsView.vue b/web/admin-spa/src/views/SettingsView.vue
index a42ce79b..c60651e6 100644
--- a/web/admin-spa/src/views/SettingsView.vue
+++ b/web/admin-spa/src/views/SettingsView.vue
@@ -720,7 +720,7 @@
                     </div>
                     <div>
                       <h2 class="text-lg font-semibold text-gray-800 dark:text-gray-200">
-                        全局会话绑定
+                        强制会话绑定
                       </h2>
                       <p class="mt-1 text-sm text-gray-600 dark:text-gray-400">
                         启用后，系统会将原始会话 ID 绑定到首次使用的账户，确保上下文的一致性
@@ -777,7 +777,7 @@
                     @change="saveClaudeConfig"
                   ></textarea>
                   <p class="mt-1 text-xs text-gray-500 dark:text-gray-400">
-                    当绑定的账户不可用（状态异常、过载等）时，返回给客户端的错误消息
+                    当检测到为旧的sessionId且未在系统中有调度记录时提示，返回给客户端的错误消息
                   </p>
                 </div>
               </div>
@@ -794,7 +794,7 @@
                       的请求将自动路由到同一账户。
                     </p>
                     <p class="mt-2 text-sm text-purple-700 dark:text-purple-300">
-                      <strong>新会话识别：</strong>如果是已存在的绑定会话但请求中
+                      <strong>新会话识别：</strong>如果绑定会话历史中没有该sessionId但请求中
                       <code class="rounded bg-purple-100 px-1 dark:bg-purple-800"
                         >messages.length > 1</code
                       >， 系统会认为这是一个污染的会话并拒绝请求。