diff --git a/scripts/validate_message_codes.py b/scripts/validate_message_codes.py
new file mode 100644
index 0000000..2998055
--- /dev/null
+++ b/scripts/validate_message_codes.py
@@ -0,0 +1,202 @@
+#!/usr/bin/env python3
+"""
+訊息代碼驗證腳本
+
+驗證後端訊息代碼、前端常量和翻譯文件的一致性。
+確保所有訊息代碼都有對應的定義和翻譯。
+
+使用方式：
+    python scripts/validate_message_codes.py
+"""
+
+import json
+import re
+import sys
+from pathlib import Path
+
+
+def extract_backend_codes():
+    """從後端 Python 文件中提取所有訊息代碼"""
+    codes = set()
+
+    # 讀取 MessageCodes 類別
+    message_codes_file = Path(
+        "src/mcp_feedback_enhanced/web/constants/message_codes.py"
+    )
+    if message_codes_file.exists():
+        content = message_codes_file.read_text(encoding="utf-8")
+        # 匹配形如 SESSION_FEEDBACK_SUBMITTED = "session.feedbackSubmitted"
+        pattern = r'([A-Z_]+)\s*=\s*"([^"]+)"'
+        matches = re.findall(pattern, content)
+        for constant_name, code in matches:
+            codes.add(code)
+
+    return codes
+
+
+def extract_frontend_codes():
+    """從前端 JavaScript 文件中提取所有訊息代碼"""
+    codes = set()
+
+    # 讀取 message-codes.js
+    message_codes_js = Path(
+        "src/mcp_feedback_enhanced/web/static/js/modules/constants/message-codes.js"
+    )
+    if message_codes_js.exists():
+        content = message_codes_js.read_text(encoding="utf-8")
+        # 匹配形如 FEEDBACK_SUBMITTED: 'session.feedbackSubmitted'
+        pattern = r'[A-Z_]+:\s*[\'"]([^\'"]+)[\'"]'
+        matches = re.findall(pattern, content)
+        codes.update(matches)
+
+    # 讀取 utils.js 中的 fallback 訊息
+    utils_js = Path("src/mcp_feedback_enhanced/web/static/js/modules/utils.js")
+    if utils_js.exists():
+        content = utils_js.read_text(encoding="utf-8")
+        # 匹配 fallbackMessages 物件中的 key
+        fallback_section = re.search(
+            r"fallbackMessages\s*=\s*\{([^}]+)\}", content, re.DOTALL
+        )
+        if fallback_section:
+            pattern = r'[\'"]([^\'"]+)[\'"]:\s*[\'"][^\'"]+[\'"]'
+            matches = re.findall(pattern, fallback_section.group(1))
+            codes.update(matches)
+
+    return codes
+
+
+def extract_translation_keys(locale="zh-TW"):
+    """從翻譯文件中提取所有 key"""
+    keys = set()
+
+    translation_file = Path(
+        f"src/mcp_feedback_enhanced/web/locales/{locale}/translation.json"
+    )
+    if translation_file.exists():
+        try:
+            data = json.loads(translation_file.read_text(encoding="utf-8"))
+
+            def extract_keys_recursive(obj, prefix=""):
+                """遞迴提取所有 key"""
+                if isinstance(obj, dict):
+                    for key, value in obj.items():
+                        full_key = f"{prefix}.{key}" if prefix else key
+                        if isinstance(value, dict):
+                            extract_keys_recursive(value, full_key)
+                        else:
+                            keys.add(full_key)
+
+            extract_keys_recursive(data)
+        except json.JSONDecodeError as e:
+            print(f"❌ 無法解析翻譯文件 {translation_file}: {e}")
+
+    return keys
+
+
+def validate_message_codes():
+    """執行驗證"""
+    print("🔍 開始驗證訊息代碼一致性...\n")
+
+    # 提取所有代碼
+    backend_codes = extract_backend_codes()
+    frontend_codes = extract_frontend_codes()
+
+    # 提取所有語言的翻譯 key
+    locales = ["zh-TW", "en", "zh-CN"]
+    translation_keys = {}
+    for locale in locales:
+        translation_keys[locale] = extract_translation_keys(locale)
+
+    # 統計資訊
+    print("📊 統計資訊：")
+    print(f"  - 後端訊息代碼數量: {len(backend_codes)}")
+    print(f"  - 前端訊息代碼數量: {len(frontend_codes)}")
+    for locale in locales:
+        print(f"  - {locale} 翻譯 key 數量: {len(translation_keys[locale])}")
+    print()
+
+    # 驗證後端代碼是否都有前端定義
+    print("🔍 檢查後端代碼是否都有前端定義...")
+    missing_in_frontend = backend_codes - frontend_codes
+    if missing_in_frontend:
+        print("❌ 以下後端代碼在前端沒有定義:")
+        for code in sorted(missing_in_frontend):
+            print(f"   - {code}")
+    else:
+        print("✅ 所有後端代碼都有前端定義")
+    print()
+
+    # 驗證前端代碼是否都有翻譯
+    print("🔍 檢查前端代碼是否都有翻譯...")
+    all_frontend_codes = backend_codes | frontend_codes
+
+    for locale in locales:
+        print(f"\n  檢查 {locale} 翻譯:")
+        missing_translations = set()
+
+        for code in all_frontend_codes:
+            if code not in translation_keys[locale]:
+                missing_translations.add(code)
+
+        if missing_translations:
+            print("  ❌ 缺少以下翻譯:")
+            for code in sorted(missing_translations):
+                print(f"     - {code}")
+        else:
+            print("  ✅ 所有代碼都有翻譯")
+
+    # 檢查是否有多餘的翻譯
+    print("\n🔍 檢查是否有多餘的翻譯...")
+    for locale in locales:
+        # 過濾掉非訊息代碼的 key（如 buttons, labels 等）
+        message_keys = {
+            k
+            for k in translation_keys[locale]
+            if any(
+                k.startswith(prefix)
+                for prefix in [
+                    "system.",
+                    "session.",
+                    "settings.",
+                    "error.",
+                    "command.",
+                    "file.",
+                    "prompt.",
+                    "notification.",
+                ]
+            )
+        }
+
+        extra_translations = message_keys - all_frontend_codes
+        if extra_translations:
+            print(f"\n  {locale} 有多餘的翻譯:")
+            for key in sorted(extra_translations):
+                print(f"     - {key}")
+
+    print("\n✅ 驗證完成！")
+
+    # 返回是否有錯誤
+    return len(missing_in_frontend) == 0 and all(
+        len(
+            [
+                code
+                for code in all_frontend_codes
+                if code not in translation_keys[locale]
+            ]
+        )
+        == 0
+        for locale in locales
+    )
+
+
+if __name__ == "__main__":
+    # 切換到專案根目錄
+    script_dir = Path(__file__).parent
+    project_root = script_dir.parent
+    import os
+
+    os.chdir(project_root)
+
+    # 執行驗證
+    success = validate_message_codes()
+    sys.exit(0 if success else 1)
diff --git a/src/mcp_feedback_enhanced/web/constants/__init__.py b/src/mcp_feedback_enhanced/web/constants/__init__.py
new file mode 100644
index 0000000..550b401
--- /dev/null
+++ b/src/mcp_feedback_enhanced/web/constants/__init__.py
@@ -0,0 +1,8 @@
+"""
+Web 常量模組
+"""
+
+from .message_codes import MessageCodes, get_message_code
+
+
+__all__ = ["MessageCodes", "get_message_code"]
diff --git a/src/mcp_feedback_enhanced/web/constants/message_codes.py b/src/mcp_feedback_enhanced/web/constants/message_codes.py
new file mode 100644
index 0000000..28df091
--- /dev/null
+++ b/src/mcp_feedback_enhanced/web/constants/message_codes.py
@@ -0,0 +1,173 @@
+"""
+統一的訊息代碼定義
+
+這個模組定義了所有後端使用的訊息代碼常量。
+前端會根據這些代碼顯示對應的本地化訊息。
+
+使用方式：
+    from ..constants import MessageCodes, get_message_code
+
+    # 使用常量
+    code = MessageCodes.SESSION_FEEDBACK_SUBMITTED
+
+    # 或使用輔助函數
+    code = get_message_code("SESSION_FEEDBACK_SUBMITTED")
+"""
+
+
+class MessageCodes:
+    """訊息代碼常量類"""
+
+    # ========== 系統相關 ==========
+    SYSTEM_CONNECTION_ESTABLISHED = "system.connectionEstablished"
+    SYSTEM_CONNECTION_LOST = "system.connectionLost"
+    SYSTEM_CONNECTION_RECONNECTING = "system.connectionReconnecting"
+    SYSTEM_CONNECTION_RECONNECTED = "system.connectionReconnected"
+    SYSTEM_CONNECTION_FAILED = "system.connectionFailed"
+    SYSTEM_WEBSOCKET_ERROR = "system.websocketError"
+    SYSTEM_WEBSOCKET_READY = "system.websocketReady"
+    SYSTEM_MEMORY_PRESSURE = "system.memoryPressure"
+    SYSTEM_SHUTDOWN = "system.shutdown"
+    SYSTEM_PROCESS_KILLED = "system.processKilled"
+    SYSTEM_HEARTBEAT_STOPPED = "system.heartbeatStopped"
+
+    # ========== 會話相關 ==========
+    SESSION_NO_ACTIVE = "session.noActiveSession"
+    SESSION_CREATED = "session.created"
+    SESSION_UPDATED = "session.updated"
+    SESSION_EXPIRED = "session.expired"
+    SESSION_TIMEOUT = "session.timeout"
+    SESSION_CLEANED = "session.cleaned"
+    SESSION_FEEDBACK_SUBMITTED = "session.feedbackSubmitted"
+    SESSION_USER_MESSAGE_RECORDED = "session.userMessageRecorded"
+    SESSION_HISTORY_SAVED = "session.historySaved"
+    SESSION_HISTORY_LOADED = "session.historyLoaded"
+    SESSION_MANUAL_CLEANUP = "session.manualCleanup"
+    SESSION_ERROR_CLEANUP = "session.errorCleanup"
+
+    # ========== 設定相關 ==========
+    SETTINGS_SAVED = "settingsAPI.saved"
+    SETTINGS_LOADED = "settingsAPI.loaded"
+    SETTINGS_CLEARED = "settingsAPI.cleared"
+    SETTINGS_SAVE_FAILED = "settingsAPI.saveFailed"
+    SETTINGS_LOAD_FAILED = "settingsAPI.loadFailed"
+    SETTINGS_CLEAR_FAILED = "settingsAPI.clearFailed"
+    SETTINGS_SET_FAILED = "settingsAPI.setFailed"
+    SETTINGS_INVALID_VALUE = "settingsAPI.invalidValue"
+    SETTINGS_LOG_LEVEL_UPDATED = "settingsAPI.logLevelUpdated"
+    SETTINGS_INVALID_LOG_LEVEL = "settingsAPI.invalidLogLevel"
+
+    # ========== 命令執行相關 ==========
+    COMMAND_EXECUTING = "commandStatus.executing"
+    COMMAND_COMPLETED = "commandStatus.completed"
+    COMMAND_FAILED = "commandStatus.failed"
+    COMMAND_INVALID = "commandStatus.invalid"
+    COMMAND_OUTPUT_RECEIVED = "commandStatus.outputReceived"
+    COMMAND_ERROR = "commandStatus.error"
+
+    # ========== 錯誤相關 ==========
+    ERROR_GENERIC = "error.generic"
+    ERROR_NETWORK = "error.network"
+    ERROR_SERVER = "error.server"
+    ERROR_TIMEOUT = "error.timeout"
+    ERROR_INVALID_INPUT = "error.invalidInput"
+    ERROR_OPERATION_FAILED = "error.operationFailed"
+    ERROR_USER_MESSAGE_FAILED = "error.userMessageFailed"
+    ERROR_GET_SESSIONS_FAILED = "error.getSessionsFailed"
+    ERROR_GET_LOG_LEVEL_FAILED = "error.getLogLevelFailed"
+    ERROR_RESOURCE_CLEANUP = "error.resourceCleanup"
+    ERROR_PROCESSING = "error.processing"
+
+    # ========== 檔案相關 ==========
+    FILE_UPLOAD_SUCCESS = "file.uploadSuccess"
+    FILE_UPLOAD_FAILED = "file.uploadFailed"
+    FILE_SIZE_TOO_LARGE = "file.sizeTooLarge"
+    FILE_TYPE_NOT_SUPPORTED = "file.typeNotSupported"
+    FILE_PROCESSING = "file.processing"
+    FILE_REMOVED = "file.removed"
+
+    # ========== 提示詞相關 ==========
+    PROMPT_SAVED = "prompt.saved"
+    PROMPT_DELETED = "prompt.deleted"
+    PROMPT_APPLIED = "prompt.applied"
+    PROMPT_IMPORT_SUCCESS = "prompt.importSuccess"
+    PROMPT_IMPORT_FAILED = "prompt.importFailed"
+    PROMPT_EXPORT_SUCCESS = "prompt.exportSuccess"
+    PROMPT_VALIDATION_FAILED = "prompt.validationFailed"
+
+
+# 向後兼容的映射表（從舊的 key 到新的常量名稱）
+LEGACY_KEY_MAPPING = {
+    # feedback_session.py 的舊 key
+    "FEEDBACK_SUBMITTED": "SESSION_FEEDBACK_SUBMITTED",
+    "SESSION_CLEANUP": "SESSION_CLEANED",
+    "TIMEOUT_CLEANUP": "SESSION_TIMEOUT",
+    "EXPIRED_CLEANUP": "SESSION_EXPIRED",
+    "MEMORY_PRESSURE_CLEANUP": "SYSTEM_MEMORY_PRESSURE",
+    "MANUAL_CLEANUP": "SESSION_MANUAL_CLEANUP",
+    "ERROR_CLEANUP": "SESSION_ERROR_CLEANUP",
+    "SHUTDOWN_CLEANUP": "SYSTEM_SHUTDOWN",
+    "COMMAND_EXECUTING": "COMMAND_EXECUTING",
+    "COMMAND_COMPLETED": "COMMAND_COMPLETED",
+    "COMMAND_FAILED": "COMMAND_FAILED",
+    "COMMAND_INVALID": "COMMAND_INVALID",
+    "COMMAND_ERROR": "COMMAND_ERROR",
+    "PROCESS_KILLED": "SYSTEM_PROCESS_KILLED",
+    "RESOURCE_CLEANUP_ERROR": "ERROR_RESOURCE_CLEANUP",
+    "HEARTBEAT_STOPPED": "SYSTEM_HEARTBEAT_STOPPED",
+    "PROCESSING_ERROR": "ERROR_PROCESSING",
+    "WEBSOCKET_READY": "SYSTEM_WEBSOCKET_READY",
+    # main_routes.py 的舊 key
+    "no_active_session": "SESSION_NO_ACTIVE",
+    "websocket_connected": "SYSTEM_CONNECTION_ESTABLISHED",
+    "new_session_created": "SESSION_CREATED",
+    "user_message_recorded": "SESSION_USER_MESSAGE_RECORDED",
+    "add_user_message_failed": "ERROR_USER_MESSAGE_FAILED",
+    "settings_saved": "SETTINGS_SAVED",
+    "save_failed": "SETTINGS_SAVE_FAILED",
+    "load_failed": "SETTINGS_LOAD_FAILED",
+    "settings_cleared": "SETTINGS_CLEARED",
+    "clear_failed": "SETTINGS_CLEAR_FAILED",
+    "session_history_saved": "SESSION_HISTORY_SAVED",
+    "get_sessions_failed": "ERROR_GET_SESSIONS_FAILED",
+    "get_log_level_failed": "ERROR_GET_LOG_LEVEL_FAILED",
+    "invalid_log_level": "SETTINGS_INVALID_LOG_LEVEL",
+    "log_level_updated": "SETTINGS_LOG_LEVEL_UPDATED",
+    "set_failed": "SETTINGS_SET_FAILED",
+}
+
+
+def get_message_code(key: str) -> str:
+    """
+    獲取訊息代碼
+
+    支援三種輸入方式：
+    1. 直接使用常量名稱：get_message_code("SESSION_FEEDBACK_SUBMITTED")
+    2. 使用舊的 key（向後兼容）：get_message_code("FEEDBACK_SUBMITTED")
+    3. 使用小寫的舊 key（向後兼容）：get_message_code("feedback_submitted")
+
+    Args:
+        key: 訊息 key 或常量名稱
+
+    Returns:
+        訊息代碼字串（例如："session.feedbackSubmitted"）
+    """
+    # 嘗試直接從 MessageCodes 獲取
+    if hasattr(MessageCodes, key):
+        return str(getattr(MessageCodes, key))
+
+    # 嘗試從映射表獲取（支援大寫和小寫）
+    upper_key = key.upper()
+    if upper_key in LEGACY_KEY_MAPPING:
+        constant_name = LEGACY_KEY_MAPPING[upper_key]
+        if hasattr(MessageCodes, constant_name):
+            return str(getattr(MessageCodes, constant_name))
+
+    # 如果是小寫的 key，也嘗試映射
+    if key in LEGACY_KEY_MAPPING:
+        constant_name = LEGACY_KEY_MAPPING[key]
+        if hasattr(MessageCodes, constant_name):
+            return str(getattr(MessageCodes, constant_name))
+
+    # 如果都找不到，返回一個預設格式
+    return f"unknown.{key}"
diff --git a/src/mcp_feedback_enhanced/web/locales/en/translation.json b/src/mcp_feedback_enhanced/web/locales/en/translation.json
index fbfb975..55454cf 100644
--- a/src/mcp_feedback_enhanced/web/locales/en/translation.json
+++ b/src/mcp_feedback_enhanced/web/locales/en/translation.json
@@ -50,7 +50,8 @@
         "sendFailed": "Send failed, please retry",
         "noContent": "No content to copy",
         "copySuccess": "Content copied to clipboard",
-        "copyFailed": "Failed to copy"
+        "copyFailed": "Failed to copy",
+        "provideTextOrImage": "Please provide feedback text or upload an image"
     },
     "summary": {
         "title": "📋 AI Work Summary",
@@ -96,7 +97,7 @@
         "summaryTitle": "📋 AI Work Summary",
         "feedbackTitle": "💬 Provide Feedback"
     },
-    "settings": {
+    "settingsUI": {
         "title": "⚙️ Settings",
         "language": "🌍 Language",
         "currentLanguage": "Current Language",
@@ -195,7 +196,7 @@
         "upload": "Upload",
         "download": "Download"
     },
-    "session": {
+    "sessionTimeout": {
         "timeout": "⏰ Session has timed out, interface will close automatically",
         "timeoutWarning": "Session is about to timeout",
         "timeoutDescription": "Due to prolonged inactivity, the session has timed out. The interface will automatically close in 3 seconds.",
@@ -261,7 +262,10 @@
             "clearSuccess": "Session history cleared successfully",
             "clearTitle": "Clear all session history records",
             "description": "Manage locally stored session history records, including retention period settings and data export functionality",
-            "exportDescription": "Export or clear locally stored session history records"
+            "exportDescription": "Export or clear locally stored session history records",
+            "exportFailed": "Export failed: {error}",
+            "clearFailed": "Clear failed: {error}",
+            "clearFailedGeneric": "Clear failed"
         },
         "retention": {
             "24hours": "24 hours",
@@ -296,6 +300,14 @@
             "clearAllTitle": "Clear all user message records from all sessions",
             "confirmClearAll": "Are you sure you want to clear all user message records from all sessions? This action cannot be undone.",
             "clearSuccess": "User message records cleared successfully"
+        },
+        "noActiveSession": "No active session data",
+        "sessionNotFound": "Session data not found",
+        "currentSession": {
+            "noData": "No current session data",
+            "noUserMessages": "Current session has no user message records",
+            "copyFailed": "Copy failed, please try again",
+            "dataManagerNotInit": "Data manager not initialized"
         }
     },
     "connectionMonitor": {
@@ -440,7 +452,8 @@
         "countdownLabel": "Submit Countdown",
         "pauseCountdown": "Pause Countdown",
         "resumeCountdown": "Resume Countdown",
-        "paused": "Auto submit paused"
+        "paused": "Auto submit paused",
+        "autoCommitNoPrompt": "Please select a prompt as auto-submit content first"
     },
     "audio": {
         "notification": {
@@ -514,5 +527,95 @@
             "permissionRequired": "Please grant notification permission first",
             "criticalTitle": "MCP Feedback - Warning"
         }
+    },
+    "system": {
+        "connectionEstablished": "WebSocket connection established",
+        "connectionLost": "WebSocket connection lost",
+        "connectionReconnecting": "Reconnecting...",
+        "connectionReconnected": "Reconnected",
+        "connectionFailed": "Connection failed",
+        "websocketError": "WebSocket error",
+        "memoryPressure": "Memory pressure cleanup",
+        "shutdown": "System shutdown",
+        "processKilled": "Process killed",
+        "heartbeatStopped": "Heartbeat stopped",
+        "websocketReady": "WebSocket ready"
+    },
+    "session": {
+        "noActiveSession": "No active session",
+        "created": "New MCP session created, page will refresh automatically",
+        "updated": "Session updated",
+        "expired": "Session expired",
+        "timeout": "Session timed out",
+        "cleaned": "Session cleaned",
+        "feedbackSubmitted": "Feedback submitted successfully",
+        "userMessageRecorded": "User message recorded",
+        "historySaved": "Session history saved ({{count}} sessions)",
+        "historyLoaded": "Session history loaded"
+    },
+    "settingsAPI": {
+        "saved": "Settings saved",
+        "loaded": "Settings loaded",
+        "cleared": "Settings cleared",
+        "saveFailed": "Save failed",
+        "loadFailed": "Load failed",
+        "clearFailed": "Clear failed",
+        "setFailed": "Set failed",
+        "invalidValue": "Invalid setting value",
+        "logLevelUpdated": "Log level updated",
+        "invalidLogLevel": "Invalid log level, must be one of DEBUG, INFO, WARN, ERROR"
+    },
+    "file": {
+        "uploadSuccess": "File uploaded successfully",
+        "uploadFailed": "File upload failed",
+        "sizeTooLarge": "File size exceeds limit",
+        "typeNotSupported": "File type not supported",
+        "processing": "Processing file...",
+        "removed": "File removed"
+    },
+    "prompt": {
+        "saved": "Prompt saved",
+        "deleted": "Prompt deleted",
+        "applied": "Prompt applied: {{name}}",
+        "importSuccess": "Prompts imported successfully",
+        "importFailed": "Prompts import failed",
+        "exportSuccess": "Prompts exported successfully",
+        "validationFailed": "Prompt validation failed"
+    },
+    "error": {
+        "generic": "An error occurred: {{error}}",
+        "network": "Network error",
+        "server": "Server error",
+        "timeout": "Operation timed out",
+        "invalidInput": "Invalid input",
+        "operationFailed": "Operation failed",
+        "userMessageFailed": "Failed to add user message",
+        "getSessionsFailed": "Failed to get sessions",
+        "getLogLevelFailed": "Failed to get log level",
+        "command": "Command execution error",
+        "resourceCleanup": "Resource cleanup error",
+        "processing": "Processing error"
+    },
+    "commandStatus": {
+        "executing": "Executing command...",
+        "completed": "Command completed",
+        "failed": "Command failed",
+        "outputReceived": "Output received",
+        "invalid": "Invalid command",
+        "error": "Command execution error"
+    },
+    "utils": {
+        "copySuccess": "Copied to clipboard",
+        "copyError": "Copy failed"
+    },
+    "fileUpload": {
+        "fileSizeExceeded": "Image size exceeds limit ({limit}): {filename}",
+        "maxFilesExceeded": "Maximum {maxFiles} files can be uploaded",
+        "processingFailed": "File processing failed, please retry"
+    },
+    "aria": {
+        "toggleAutoSubmit": "Toggle auto submit",
+        "toggleNotification": "Toggle notification",
+        "toggleAudioNotification": "Toggle audio notification"
     }
 }
diff --git a/src/mcp_feedback_enhanced/web/locales/zh-CN/translation.json b/src/mcp_feedback_enhanced/web/locales/zh-CN/translation.json
index ae68858..c4b90a4 100644
--- a/src/mcp_feedback_enhanced/web/locales/zh-CN/translation.json
+++ b/src/mcp_feedback_enhanced/web/locales/zh-CN/translation.json
@@ -50,7 +50,8 @@
         "sendFailed": "发送失败，请重试",
         "noContent": "没有可复制的内容",
         "copySuccess": "内容已复制到剪贴板",
-        "copyFailed": "复制失败"
+        "copyFailed": "复制失败",
+        "provideTextOrImage": "请提供反馈文字或上传图片"
     },
     "summary": {
         "title": "📋 AI 工作摘要",
@@ -96,7 +97,7 @@
         "summaryTitle": "📋 AI 工作摘要",
         "feedbackTitle": "💬 提供反馈"
     },
-    "settings": {
+    "settingsUI": {
         "title": "⚙️ 设定",
         "language": "🌍 语言",
         "currentLanguage": "当前语言",
@@ -121,7 +122,8 @@
         "resetError": "重置设定时发生错误",
         "timeout": "连线逾时 (秒)",
         "autorefresh": "自动重新整理",
-        "debug": "除错模式"
+        "debug": "除错模式",
+        "autoCommitNoPrompt": "请先选择一个提示词作为自动提交内容"
     },
     "languages": {
         "zh-TW": "繁體中文",
@@ -195,7 +197,7 @@
         "upload": "上传",
         "download": "下载"
     },
-    "session": {
+    "sessionTimeout": {
         "timeout": "⏰ 会话已超时，界面将自动关闭",
         "timeoutWarning": "会话即将超时",
         "timeoutDescription": "由于长时间无响应，会话已超时。界面将在 3 秒后自动关闭。",
@@ -261,7 +263,10 @@
             "clearSuccess": "会话历史已清空",
             "clearTitle": "清空所有会话历史记录",
             "description": "管理本地存储的会话历史记录，包括保存期限设定和数据导出功能",
-            "exportDescription": "导出或清空本地存储的会话历史记录"
+            "exportDescription": "导出或清空本地存储的会话历史记录",
+            "exportFailed": "导出失败: {error}",
+            "clearFailed": "清空失败: {error}",
+            "clearFailedGeneric": "清空失败"
         },
         "retention": {
             "24hours": "24 小时",
@@ -296,6 +301,14 @@
             "clearAllTitle": "清空所有会话的用户消息记录",
             "confirmClearAll": "确定要清空所有会话的用户消息记录吗？此操作无法撤销。",
             "clearSuccess": "用户消息记录已清空"
+        },
+        "noActiveSession": "目前没有活跃的会话数据",
+        "sessionNotFound": "找不到会话资料",
+        "currentSession": {
+            "noData": "没有当前会话数据",
+            "noUserMessages": "当前会话没有用户消息记录",
+            "copyFailed": "复制失败，请重试",
+            "dataManagerNotInit": "数据管理器未初始化"
         }
     },
     "connectionMonitor": {
@@ -513,5 +526,82 @@
             "permissionRequired": "请先授权通知权限",
             "criticalTitle": "MCP Feedback - 警告"
         }
+    },
+    "system": {
+        "connectionEstablished": "WebSocket 连接已建立",
+        "connectionLost": "WebSocket 连接已断开",
+        "connectionReconnecting": "正在重新连接...",
+        "connectionReconnected": "已重新连接",
+        "connectionFailed": "连接失败",
+        "websocketError": "WebSocket 错误"
+    },
+    "session": {
+        "noActiveSession": "没有活跃会话",
+        "created": "新的 MCP 会话已创建，页面将自动刷新",
+        "updated": "会话已更新",
+        "expired": "会话已过期",
+        "timeout": "会话已超时",
+        "cleaned": "会话已清理",
+        "feedbackSubmitted": "反馈已成功提交",
+        "userMessageRecorded": "用户消息已记录",
+        "historySaved": "会话历史已保存（{{count}} 个会话）",
+        "historyLoaded": "会话历史已载入"
+    },
+    "settingsAPI": {
+        "saved": "设置已保存",
+        "loaded": "设置已载入",
+        "cleared": "设置已清除",
+        "saveFailed": "保存失败",
+        "loadFailed": "加载失败",
+        "clearFailed": "清除失败",
+        "invalidValue": "无效的设置值",
+        "logLevelUpdated": "日志等级已更新",
+        "invalidLogLevel": "无效的日志等级，必须是 DEBUG, INFO, WARN, ERROR 之一"
+    },
+    "file": {
+        "uploadSuccess": "文件上传成功",
+        "uploadFailed": "文件上传失败",
+        "sizeTooLarge": "文件大小超过限制",
+        "typeNotSupported": "不支持的文件类型",
+        "processing": "正在处理文件...",
+        "removed": "文件已移除"
+    },
+    "prompt": {
+        "saved": "提示词已保存",
+        "deleted": "提示词已删除",
+        "applied": "已套用提示词：{{name}}",
+        "importSuccess": "提示词导入成功",
+        "importFailed": "提示词导入失败",
+        "exportSuccess": "提示词导出成功",
+        "validationFailed": "提示词验证失败"
+    },
+    "error": {
+        "generic": "发生错误：{{error}}",
+        "network": "网络错误",
+        "server": "服务器错误",
+        "timeout": "操作超时",
+        "invalidInput": "输入无效",
+        "operationFailed": "操作失败"
+    },
+    "commandStatus": {
+        "executing": "正在执行命令...",
+        "completed": "命令执行完成",
+        "failed": "命令执行失败",
+        "outputReceived": "已接收输出",
+        "invalid": "无效的命令"
+    },
+    "utils": {
+        "copySuccess": "已复制到剪贴板",
+        "copyError": "复制失败"
+    },
+    "fileUpload": {
+        "fileSizeExceeded": "图片大小超过限制 ({limit}): {filename}",
+        "maxFilesExceeded": "最多只能上传 {maxFiles} 个文件",
+        "processingFailed": "文件处理失败，请重试"
+    },
+    "aria": {
+        "toggleAutoSubmit": "切换自动提交",
+        "toggleNotification": "切换通知",
+        "toggleAudioNotification": "切换音效通知"
     }
 }
diff --git a/src/mcp_feedback_enhanced/web/locales/zh-TW/translation.json b/src/mcp_feedback_enhanced/web/locales/zh-TW/translation.json
index 0d8073b..694a433 100644
--- a/src/mcp_feedback_enhanced/web/locales/zh-TW/translation.json
+++ b/src/mcp_feedback_enhanced/web/locales/zh-TW/translation.json
@@ -55,7 +55,8 @@
         "sendFailed": "發送失敗，請重試",
         "noContent": "沒有可複製的內容",
         "copySuccess": "內容已複製到剪貼板",
-        "copyFailed": "複製失敗"
+        "copyFailed": "複製失敗",
+        "provideTextOrImage": "請提供回饋文字或上傳圖片"
     },
     "summary": {
         "title": "📋 AI 工作摘要",
@@ -101,7 +102,7 @@
         "summaryTitle": "📋 AI 工作摘要",
         "feedbackTitle": "💬 提供回饋"
     },
-    "settings": {
+    "settingsUI": {
         "title": "⚙️ 設定",
         "language": "🌍 語言",
         "currentLanguage": "當前語言",
@@ -126,7 +127,8 @@
         "resetError": "重置設定時發生錯誤",
         "timeout": "連線逾時 (秒)",
         "autorefresh": "自動重新整理",
-        "debug": "除錯模式"
+        "debug": "除錯模式",
+        "autoCommitNoPrompt": "請先選擇一個提示詞作為自動提交內容"
     },
     "languages": {
         "zh-TW": "繁體中文",
@@ -200,7 +202,7 @@
         "upload": "上傳",
         "download": "下載"
     },
-    "session": {
+    "sessionTimeout": {
         "timeout": "⏰ 會話已超時，介面將自動關閉",
         "timeoutWarning": "會話即將超時",
         "timeoutDescription": "由於長時間無回應，會話已超時。介面將在 3 秒後自動關閉。",
@@ -266,7 +268,10 @@
             "clearSuccess": "會話歷史已清空",
             "clearTitle": "清空所有會話歷史記錄",
             "description": "管理本地儲存的會話歷史記錄，包括保存期限設定和資料匯出功能",
-            "exportDescription": "匯出或清空本地儲存的會話歷史記錄"
+            "exportDescription": "匯出或清空本地儲存的會話歷史記錄",
+            "exportFailed": "匯出失敗: {error}",
+            "clearFailed": "清空失敗: {error}",
+            "clearFailedGeneric": "清空失敗"
         },
         "retention": {
             "24hours": "24 小時",
@@ -301,6 +306,14 @@
             "clearAllTitle": "清空所有會話的用戶訊息記錄",
             "confirmClearAll": "確定要清空所有會話的用戶訊息記錄嗎？此操作無法復原。",
             "clearSuccess": "用戶訊息記錄已清空"
+        },
+        "noActiveSession": "目前沒有活躍的會話數據",
+        "sessionNotFound": "找不到會話資料",
+        "currentSession": {
+            "noData": "沒有當前會話數據",
+            "noUserMessages": "當前會話沒有用戶消息記錄",
+            "copyFailed": "複製失敗，請重試",
+            "dataManagerNotInit": "數據管理器未初始化"
         }
     },
     "connectionMonitor": {
@@ -518,5 +531,95 @@
             "permissionRequired": "請先授權通知權限",
             "criticalTitle": "MCP Feedback - 警告"
         }
+    },
+    "system": {
+        "connectionEstablished": "WebSocket 連接已建立",
+        "connectionLost": "WebSocket 連接已斷開",
+        "connectionReconnecting": "正在重新連接...",
+        "connectionReconnected": "已重新連接",
+        "connectionFailed": "連接失敗",
+        "websocketError": "WebSocket 錯誤",
+        "memoryPressure": "記憶體壓力清理",
+        "shutdown": "系統關閉",
+        "processKilled": "進程已終止",
+        "heartbeatStopped": "心跳已停止",
+        "websocketReady": "WebSocket 已就緒"
+    },
+    "session": {
+        "noActiveSession": "沒有活躍會話",
+        "created": "新的 MCP 會話已創建，頁面將自動刷新",
+        "updated": "會話已更新",
+        "expired": "會話已過期",
+        "timeout": "會話已超時",
+        "cleaned": "會話已清理",
+        "feedbackSubmitted": "反饋已成功提交",
+        "userMessageRecorded": "用戶消息已記錄",
+        "historySaved": "會話歷史已保存（{{count}} 個會話）",
+        "historyLoaded": "會話歷史已載入"
+    },
+    "settingsAPI": {
+        "saved": "設定已保存",
+        "loaded": "設定已載入",
+        "cleared": "設定已清除",
+        "saveFailed": "保存失敗",
+        "loadFailed": "載入失敗",
+        "clearFailed": "清除失敗",
+        "setFailed": "設定失敗",
+        "invalidValue": "無效的設定值",
+        "logLevelUpdated": "日誌等級已更新",
+        "invalidLogLevel": "無效的日誌等級，必須是 DEBUG, INFO, WARN, ERROR 之一"
+    },
+    "file": {
+        "uploadSuccess": "檔案上傳成功",
+        "uploadFailed": "檔案上傳失敗",
+        "sizeTooLarge": "檔案大小超過限制",
+        "typeNotSupported": "不支援的檔案類型",
+        "processing": "正在處理檔案...",
+        "removed": "檔案已移除"
+    },
+    "prompt": {
+        "saved": "提示詞已保存",
+        "deleted": "提示詞已刪除",
+        "applied": "已套用提示詞：{{name}}",
+        "importSuccess": "提示詞匯入成功",
+        "importFailed": "提示詞匯入失敗",
+        "exportSuccess": "提示詞匯出成功",
+        "validationFailed": "提示詞驗證失敗"
+    },
+    "error": {
+        "generic": "發生錯誤：{{error}}",
+        "network": "網絡錯誤",
+        "server": "伺服器錯誤",
+        "timeout": "操作超時",
+        "invalidInput": "輸入無效",
+        "operationFailed": "操作失敗",
+        "userMessageFailed": "添加用戶消息失敗",
+        "getSessionsFailed": "獲取會話列表失敗",
+        "getLogLevelFailed": "獲取日誌等級失敗",
+        "command": "命令執行錯誤",
+        "resourceCleanup": "資源清理錯誤",
+        "processing": "處理過程錯誤"
+    },
+    "commandStatus": {
+        "executing": "正在執行命令...",
+        "completed": "命令執行完成",
+        "failed": "命令執行失敗",
+        "outputReceived": "已接收輸出",
+        "invalid": "無效的命令",
+        "error": "命令執行錯誤"
+    },
+    "utils": {
+        "copySuccess": "已複製到剪貼板",
+        "copyError": "複製失敗"
+    },
+    "fileUpload": {
+        "fileSizeExceeded": "圖片大小超過限制 ({limit}): {filename}",
+        "maxFilesExceeded": "最多只能上傳 {maxFiles} 個檔案",
+        "processingFailed": "檔案處理失敗，請重試"
+    },
+    "aria": {
+        "toggleAutoSubmit": "切換自動提交",
+        "toggleNotification": "切換通知",
+        "toggleAudioNotification": "切換音效通知"
     }
 }
diff --git a/src/mcp_feedback_enhanced/web/main.py b/src/mcp_feedback_enhanced/web/main.py
index 90111c2..5e3161b 100644
--- a/src/mcp_feedback_enhanced/web/main.py
+++ b/src/mcp_feedback_enhanced/web/main.py
@@ -23,7 +23,6 @@ from fastapi.staticfiles import StaticFiles
 from fastapi.templating import Jinja2Templates
 
 from ..debug import web_debug_log as debug_log
-from ..i18n import get_i18n_manager
 from ..utils.error_handler import ErrorHandler, ErrorType
 from ..utils.memory_monitor import get_memory_monitor
 from .models import CleanupReason, SessionStatus, WebFeedbackSession
@@ -137,7 +136,7 @@ class WebUIManager:
     def _init_basic_components(self):
         """同步初始化基本組件"""
         # 基本組件初始化（必須同步）
-        self.i18n = get_i18n_manager()
+        # 移除 i18n 管理器，因為翻譯已移至前端
 
         # 設置靜態文件和模板（必須同步）
         self._setup_static_files()
@@ -181,9 +180,8 @@ class WebUIManager:
 
         def preload_i18n():
             try:
-                # 觸發翻譯載入（如果尚未載入）
-                self.i18n.get_supported_languages()
-                debug_log("I18N 資源預載入完成")
+                # I18N 在前端處理，這裡只記錄預載入完成
+                debug_log("I18N 資源預載入完成（前端處理）")
                 return True
             except Exception as e:
                 debug_log(f"I18N 資源預載入失敗: {e}")
@@ -733,7 +731,7 @@ class WebUIManager:
             refresh_message = {
                 "type": "session_updated",
                 "action": "new_session_created",
-                "message": "新的 MCP 會話已創建，頁面將自動刷新",
+                "messageCode": "session.created",
                 "session_info": {
                     "session_id": self.current_session.session_id,
                     "project_directory": self.current_session.project_directory,
diff --git a/src/mcp_feedback_enhanced/web/models/feedback_session.py b/src/mcp_feedback_enhanced/web/models/feedback_session.py
index d1ac589..19de970 100644
--- a/src/mcp_feedback_enhanced/web/models/feedback_session.py
+++ b/src/mcp_feedback_enhanced/web/models/feedback_session.py
@@ -26,6 +26,7 @@ from fastapi import WebSocket
 from ...debug import web_debug_log as debug_log
 from ...utils.error_handler import ErrorHandler, ErrorType
 from ...utils.resource_manager import get_resource_manager, register_process
+from ..constants import get_message_code
 
 
 class SessionStatus(Enum):
@@ -63,6 +64,9 @@ SUPPORTED_IMAGE_TYPES = {
 }
 TEMP_DIR = Path.home() / ".cache" / "interactive-feedback-mcp-web"
 
+# 訊息代碼現在從統一的常量文件導入
+# 使用 get_message_code 函數來獲取訊息代碼
+
 
 def _safe_parse_command(command: str) -> list[str]:
     """
@@ -135,6 +139,7 @@ class WebFeedbackSession:
         self.command_logs: list[str] = []
         self.user_messages: list[dict] = []  # 用戶消息記錄
         self._cleanup_done = False  # 防止重複清理
+        # 移除語言設定，改由前端處理
 
         # 新增：會話狀態管理
         self.status = SessionStatus.WAITING
@@ -176,6 +181,18 @@ class WebFeedbackSession:
             f"會話 {self.session_id} 初始化完成，自動清理延遲: {auto_cleanup_delay}秒，最大空閒: {max_idle_time}秒"
         )
 
+    def get_message_code(self, key: str) -> str:
+        """
+        獲取訊息代碼
+
+        Args:
+            key: 訊息 key
+
+        Returns:
+            訊息代碼（用於前端 i18n）
+        """
+        return get_message_code(key)
+
     def next_step(self, message: str | None = None) -> bool:
         """進入下一個狀態 - 單向流轉，不可倒退"""
         old_status = self.status
@@ -484,8 +501,9 @@ class WebFeedbackSession:
             try:
                 await self.websocket.send_json(
                     {
-                        "type": "feedback_received",
-                        "message": "反饋已成功提交",
+                        "type": "notification",
+                        "code": self.get_message_code("FEEDBACK_SUBMITTED"),
+                        "severity": "success",
                         "status": self.status.value,
                     }
                 )
@@ -738,21 +756,24 @@ class WebFeedbackSession:
             # 2. 關閉 WebSocket 連接
             if self.websocket:
                 try:
-                    # 根據清理原因發送不同的通知消息
-                    message_map = {
-                        CleanupReason.TIMEOUT: "會話已超時，介面將自動關閉",
-                        CleanupReason.EXPIRED: "會話已過期，介面將自動關閉",
-                        CleanupReason.MEMORY_PRESSURE: "系統內存不足，會話將被清理",
-                        CleanupReason.MANUAL: "會話已被手動清理",
-                        CleanupReason.ERROR: "會話發生錯誤，將被清理",
-                        CleanupReason.SHUTDOWN: "系統正在關閉，會話將被清理",
+                    # 根據清理原因獲取訊息代碼
+                    code_key_map = {
+                        CleanupReason.TIMEOUT: "TIMEOUT_CLEANUP",
+                        CleanupReason.EXPIRED: "EXPIRED_CLEANUP",
+                        CleanupReason.MEMORY_PRESSURE: "MEMORY_PRESSURE_CLEANUP",
+                        CleanupReason.MANUAL: "MANUAL_CLEANUP",
+                        CleanupReason.ERROR: "ERROR_CLEANUP",
+                        CleanupReason.SHUTDOWN: "SHUTDOWN_CLEANUP",
                     }
 
+                    code_key = code_key_map.get(reason, "SESSION_CLEANUP")
+
                     await self.websocket.send_json(
                         {
-                            "type": "session_cleanup",
+                            "type": "notification",
+                            "code": self.get_message_code(code_key),
+                            "severity": "warning",
                             "reason": reason.value,
-                            "message": message_map.get(reason, "會話將被清理"),
                         }
                     )
                     await asyncio.sleep(0.1)  # 給前端一點時間處理消息
diff --git a/src/mcp_feedback_enhanced/web/routes/main_routes.py b/src/mcp_feedback_enhanced/web/routes/main_routes.py
index 2e7ebdd..c3b56e4 100644
--- a/src/mcp_feedback_enhanced/web/routes/main_routes.py
+++ b/src/mcp_feedback_enhanced/web/routes/main_routes.py
@@ -16,6 +16,7 @@ from fastapi.responses import HTMLResponse, JSONResponse
 
 from ... import __version__
 from ...debug import web_debug_log as debug_log
+from ..constants import get_message_code as get_msg_code
 
 
 if TYPE_CHECKING:
@@ -44,6 +45,11 @@ def load_user_layout_settings() -> str:
         return "combined-vertical"
 
 
+# 使用統一的訊息代碼系統
+# 從 ..constants 導入的 get_msg_code 函數會處理所有訊息代碼
+# 舊的 key 會自動映射到新的常量
+
+
 def setup_routes(manager: "WebUIManager"):
     """設置路由"""
 
@@ -79,7 +85,6 @@ def setup_routes(manager: "WebUIManager"):
                 "version": __version__,
                 "has_session": True,
                 "layout_mode": layout_mode,
-                "i18n": manager.i18n,
             },
         )
 
@@ -113,16 +118,23 @@ def setup_routes(manager: "WebUIManager"):
         return JSONResponse(content=translations)
 
     @manager.app.get("/api/session-status")
-    async def get_session_status():
+    async def get_session_status(request: Request):
         """獲取當前會話狀態"""
         current_session = manager.get_current_session()
 
+        # 從請求頭獲取客戶端語言
+        lang = (
+            request.headers.get("Accept-Language", "zh-TW").split(",")[0].split("-")[0]
+        )
+        if lang == "zh":
+            lang = "zh-TW"
+
         if not current_session:
             return JSONResponse(
                 content={
                     "has_session": False,
                     "status": "no_session",
-                    "message": "沒有活躍會話",
+                    "messageCode": get_msg_code("no_active_session"),
                 }
             )
 
@@ -139,12 +151,20 @@ def setup_routes(manager: "WebUIManager"):
         )
 
     @manager.app.get("/api/current-session")
-    async def get_current_session():
+    async def get_current_session(request: Request):
         """獲取當前會話詳細信息"""
         current_session = manager.get_current_session()
 
+        # 從查詢參數獲取語言，如果沒有則從會話獲取，最後使用默認值
+
         if not current_session:
-            return JSONResponse(status_code=404, content={"error": "沒有活躍會話"})
+            return JSONResponse(
+                status_code=404,
+                content={
+                    "error": "No active session",
+                    "messageCode": get_msg_code("no_active_session"),
+                },
+            )
 
         return JSONResponse(
             content={
@@ -158,8 +178,9 @@ def setup_routes(manager: "WebUIManager"):
         )
 
     @manager.app.get("/api/all-sessions")
-    async def get_all_sessions():
+    async def get_all_sessions(request: Request):
         """獲取所有會話的實時狀態"""
+
         try:
             sessions_data = []
 
@@ -189,44 +210,65 @@ def setup_routes(manager: "WebUIManager"):
         except Exception as e:
             debug_log(f"獲取所有會話狀態失敗: {e}")
             return JSONResponse(
-                status_code=500, content={"error": f"獲取會話狀態失敗: {e!s}"}
+                status_code=500,
+                content={
+                    "error": f"Failed to get sessions: {e!s}",
+                    "messageCode": get_msg_code("get_sessions_failed"),
+                },
             )
 
     @manager.app.post("/api/add-user-message")
     async def add_user_message(request: Request):
         """添加用戶消息到當前會話"""
+
         try:
             data = await request.json()
             current_session = manager.get_current_session()
 
             if not current_session:
-                return JSONResponse(status_code=404, content={"error": "沒有活躍會話"})
+                return JSONResponse(
+                    status_code=404,
+                    content={
+                        "error": "No active session",
+                        "messageCode": get_msg_code("no_active_session"),
+                    },
+                )
 
             # 添加用戶消息到會話
             current_session.add_user_message(data)
 
             debug_log(f"用戶消息已添加到會話 {current_session.session_id}")
             return JSONResponse(
-                content={"status": "success", "message": "用戶消息已記錄"}
+                content={
+                    "status": "success",
+                    "messageCode": get_msg_code("user_message_recorded"),
+                }
             )
 
         except Exception as e:
             debug_log(f"添加用戶消息失敗: {e}")
             return JSONResponse(
-                status_code=500, content={"error": f"添加用戶消息失敗: {e!s}"}
+                status_code=500,
+                content={
+                    "error": f"Failed to add user message: {e!s}",
+                    "messageCode": get_msg_code("add_user_message_failed"),
+                },
             )
 
     @manager.app.websocket("/ws")
-    async def websocket_endpoint(websocket: WebSocket):
+    async def websocket_endpoint(websocket: WebSocket, lang: str = "zh-TW"):
         """WebSocket 端點 - 重構後移除 session_id 依賴"""
         # 獲取當前活躍會話
         session = manager.get_current_session()
         if not session:
-            await websocket.close(code=4004, reason="沒有活躍會話")
+            await websocket.close(code=4004, reason="No active session")
             return
 
         await websocket.accept()
 
+        # 語言由前端處理，不需要在後端設置
+        debug_log(f"WebSocket 連接建立，語言由前端處理: {lang}")
+
         # 檢查會話是否已有 WebSocket 連接
         if session.websocket and session.websocket != websocket:
             debug_log("會話已有 WebSocket 連接，替換為新連接")
@@ -237,7 +279,10 @@ def setup_routes(manager: "WebUIManager"):
         # 發送連接成功消息
         try:
             await websocket.send_json(
-                {"type": "connection_established", "message": "WebSocket 連接已建立"}
+                {
+                    "type": "connection_established",
+                    "messageCode": get_msg_code("websocket_connected"),
+                }
             )
 
             # 檢查是否有待發送的會話更新
@@ -247,7 +292,7 @@ def setup_routes(manager: "WebUIManager"):
                     {
                         "type": "session_updated",
                         "action": "new_session_created",
-                        "message": "新會話已創建，正在更新頁面內容",
+                        "messageCode": get_msg_code("new_session_created"),
                         "session_info": {
                             "project_directory": session.project_directory,
                             "summary": session.summary,
@@ -296,6 +341,7 @@ def setup_routes(manager: "WebUIManager"):
     @manager.app.post("/api/save-settings")
     async def save_settings(request: Request):
         """保存設定到檔案"""
+
         try:
             data = await request.json()
 
@@ -310,18 +356,28 @@ def setup_routes(manager: "WebUIManager"):
 
             debug_log(f"設定已保存到: {settings_file}")
 
-            return JSONResponse(content={"status": "success", "message": "設定已保存"})
+            return JSONResponse(
+                content={
+                    "status": "success",
+                    "messageCode": get_msg_code("settings_saved"),
+                }
+            )
 
         except Exception as e:
             debug_log(f"保存設定失敗: {e}")
             return JSONResponse(
                 status_code=500,
-                content={"status": "error", "message": f"保存失敗: {e!s}"},
+                content={
+                    "status": "error",
+                    "message": f"Save failed: {e!s}",
+                    "messageCode": get_msg_code("save_failed"),
+                },
             )
 
     @manager.app.get("/api/load-settings")
-    async def load_settings():
+    async def load_settings(request: Request):
         """從檔案載入設定"""
+
         try:
             # 使用統一的設定檔案路徑
             config_dir = Path.home() / ".config" / "mcp-feedback-enhanced"
@@ -340,12 +396,17 @@ def setup_routes(manager: "WebUIManager"):
             debug_log(f"載入設定失敗: {e}")
             return JSONResponse(
                 status_code=500,
-                content={"status": "error", "message": f"載入失敗: {e!s}"},
+                content={
+                    "status": "error",
+                    "message": f"Load failed: {e!s}",
+                    "messageCode": get_msg_code("load_failed"),
+                },
             )
 
     @manager.app.post("/api/clear-settings")
-    async def clear_settings():
+    async def clear_settings(request: Request):
         """清除設定檔案"""
+
         try:
             # 使用統一的設定檔案路徑
             config_dir = Path.home() / ".config" / "mcp-feedback-enhanced"
@@ -357,18 +418,28 @@ def setup_routes(manager: "WebUIManager"):
             else:
                 debug_log("設定檔案不存在，無需刪除")
 
-            return JSONResponse(content={"status": "success", "message": "設定已清除"})
+            return JSONResponse(
+                content={
+                    "status": "success",
+                    "messageCode": get_msg_code("settings_cleared"),
+                }
+            )
 
         except Exception as e:
             debug_log(f"清除設定失敗: {e}")
             return JSONResponse(
                 status_code=500,
-                content={"status": "error", "message": f"清除失敗: {e!s}"},
+                content={
+                    "status": "error",
+                    "message": f"Clear failed: {e!s}",
+                    "messageCode": get_msg_code("clear_failed"),
+                },
             )
 
     @manager.app.get("/api/load-session-history")
-    async def load_session_history():
+    async def load_session_history(request: Request):
         """從檔案載入會話歷史"""
+
         try:
             # 使用統一的設定檔案路徑
             config_dir = Path.home() / ".config" / "mcp-feedback-enhanced"
@@ -402,12 +473,17 @@ def setup_routes(manager: "WebUIManager"):
             debug_log(f"載入會話歷史失敗: {e}")
             return JSONResponse(
                 status_code=500,
-                content={"status": "error", "message": f"載入失敗: {e!s}"},
+                content={
+                    "status": "error",
+                    "message": f"Load failed: {e!s}",
+                    "messageCode": get_msg_code("load_failed"),
+                },
             )
 
     @manager.app.post("/api/save-session-history")
     async def save_session_history(request: Request):
         """保存會話歷史到檔案"""
+
         try:
             data = await request.json()
 
@@ -435,7 +511,8 @@ def setup_routes(manager: "WebUIManager"):
             return JSONResponse(
                 content={
                     "status": "success",
-                    "message": f"會話歷史已保存（{session_count} 個會話）",
+                    "messageCode": get_msg_code("session_history_saved"),
+                    "params": {"count": session_count},
                 }
             )
 
@@ -443,12 +520,17 @@ def setup_routes(manager: "WebUIManager"):
             debug_log(f"保存會話歷史失敗: {e}")
             return JSONResponse(
                 status_code=500,
-                content={"status": "error", "message": f"保存失敗: {e!s}"},
+                content={
+                    "status": "error",
+                    "message": f"Save failed: {e!s}",
+                    "messageCode": get_msg_code("save_failed"),
+                },
             )
 
     @manager.app.get("/api/log-level")
-    async def get_log_level():
+    async def get_log_level(request: Request):
         """獲取日誌等級設定"""
+
         try:
             # 使用統一的設定檔案路徑
             config_dir = Path.home() / ".config" / "mcp-feedback-enhanced"
@@ -470,12 +552,16 @@ def setup_routes(manager: "WebUIManager"):
             debug_log(f"獲取日誌等級失敗: {e}")
             return JSONResponse(
                 status_code=500,
-                content={"error": f"獲取日誌等級失敗: {e!s}"},
+                content={
+                    "error": f"Failed to get log level: {e!s}",
+                    "messageCode": get_msg_code("get_log_level_failed"),
+                },
             )
 
     @manager.app.post("/api/log-level")
     async def set_log_level(request: Request):
         """設定日誌等級"""
+
         try:
             data = await request.json()
             log_level = data.get("logLevel")
@@ -484,7 +570,8 @@ def setup_routes(manager: "WebUIManager"):
                 return JSONResponse(
                     status_code=400,
                     content={
-                        "error": "無效的日誌等級，必須是 DEBUG, INFO, WARN, ERROR 之一"
+                        "error": "Invalid log level",
+                        "messageCode": get_msg_code("invalid_log_level"),
                     },
                 )
 
@@ -512,7 +599,7 @@ def setup_routes(manager: "WebUIManager"):
                 content={
                     "status": "success",
                     "logLevel": log_level,
-                    "message": "日誌等級已更新",
+                    "messageCode": get_msg_code("log_level_updated"),
                 }
             )
 
@@ -520,7 +607,11 @@ def setup_routes(manager: "WebUIManager"):
             debug_log(f"設定日誌等級失敗: {e}")
             return JSONResponse(
                 status_code=500,
-                content={"status": "error", "message": f"設定失敗: {e!s}"},
+                content={
+                    "status": "error",
+                    "message": f"Set failed: {e!s}",
+                    "messageCode": get_msg_code("set_failed"),
+                },
             )
 
 
diff --git a/src/mcp_feedback_enhanced/web/static/js/app.js b/src/mcp_feedback_enhanced/web/static/js/app.js
index 55f098c..1d07f3b 100644
--- a/src/mcp_feedback_enhanced/web/static/js/app.js
+++ b/src/mcp_feedback_enhanced/web/static/js/app.js
@@ -670,6 +670,11 @@
                 break;
             case 'session_updated':
                 console.log('🔄 收到會話更新訊息:', data.session_info);
+                // 處理訊息代碼
+                if (data.messageCode && window.i18nManager) {
+                    const message = window.i18nManager.t(data.messageCode);
+                    window.MCPFeedback.Utils.showMessage(message, window.MCPFeedback.Utils.CONSTANTS.MESSAGE_SUCCESS);
+                }
                 this._originalHandleSessionUpdated(data);
                 break;
             case 'desktop_close_request':
@@ -712,9 +717,20 @@
         this.uiManager.setFeedbackState(window.MCPFeedback.Utils.CONSTANTS.FEEDBACK_SUBMITTED);
         this.uiManager.setLastSubmissionTime(Date.now());
 
+        // 停止自動提交計時器（如果正在運行）
+        if (this.autoSubmitManager && this.autoSubmitManager.isEnabled) {
+            console.log('⏸️ 反饋已成功提交，停止自動提交倒數計時器');
+            this.autoSubmitManager.stop();
+        }
+
         // 顯示成功訊息
-        const successMessage = window.i18nManager ? window.i18nManager.t('feedback.submitSuccess') : '回饋提交成功！';
-        window.MCPFeedback.Utils.showMessage(data.message || successMessage, window.MCPFeedback.Utils.CONSTANTS.MESSAGE_SUCCESS);
+        if (data.messageCode && window.i18nManager) {
+            const message = window.i18nManager.t(data.messageCode, data.params);
+            window.MCPFeedback.Utils.showMessage(message, window.MCPFeedback.Utils.CONSTANTS.MESSAGE_SUCCESS);
+        } else {
+            const successMessage = window.i18nManager ? window.i18nManager.t('feedback.submitSuccess') : '回饋提交成功！';
+            window.MCPFeedback.Utils.showMessage(data.message || successMessage, window.MCPFeedback.Utils.CONSTANTS.MESSAGE_SUCCESS);
+        }
 
         // 更新 AI 摘要區域顯示「已送出反饋」狀態
         const submittedMessage = window.i18nManager ? window.i18nManager.t('feedback.submittedWaiting') : '已送出反饋，等待下次 MCP 調用...';
@@ -793,8 +809,11 @@
             }
 
             // 顯示新會話通知
+            const defaultMessage = window.i18nManager ? 
+                window.i18nManager.t('session.created') : 
+                'New MCP session created, page will refresh automatically';
             window.MCPFeedback.Utils.showMessage(
-                data.message || '新的 MCP 會話已創建，正在更新內容...',
+                data.message || defaultMessage,
                 window.MCPFeedback.Utils.CONSTANTS.MESSAGE_SUCCESS
             );
 
@@ -1101,7 +1120,10 @@
         const images = this.imageHandler ? this.imageHandler.getImages() : [];
 
         if (!feedback && images.length === 0) {
-            window.MCPFeedback.Utils.showMessage('請提供回饋文字或上傳圖片', window.MCPFeedback.Utils.CONSTANTS.MESSAGE_WARNING);
+            const message = window.i18nManager ? 
+                window.i18nManager.t('feedback.provideTextOrImage', '請提供回饋文字或上傳圖片') : 
+                '請提供回饋文字或上傳圖片';
+            window.MCPFeedback.Utils.showMessage(message, window.MCPFeedback.Utils.CONSTANTS.MESSAGE_WARNING);
             return null;
         }
 
@@ -1130,6 +1152,12 @@
                 this.uiManager.setFeedbackState(window.MCPFeedback.Utils.CONSTANTS.FEEDBACK_PROCESSING);
             }
 
+            // 停止自動提交計時器（如果正在運行）
+            if (this.autoSubmitManager && this.autoSubmitManager.isEnabled) {
+                console.log('⏸️ 手動提交反饋，停止自動提交倒數計時器');
+                this.autoSubmitManager.stop();
+            }
+
             // 3. 發送回饋到 AI 助手
             const success = this.webSocketManager.send({
                 type: 'submit_feedback',
diff --git a/src/mcp_feedback_enhanced/web/static/js/i18n.js b/src/mcp_feedback_enhanced/web/static/js/i18n.js
index e723ee5..2b5d754 100644
--- a/src/mcp_feedback_enhanced/web/static/js/i18n.js
+++ b/src/mcp_feedback_enhanced/web/static/js/i18n.js
@@ -8,10 +8,40 @@
 
 class I18nManager {
     constructor() {
-        this.currentLanguage = 'zh-CN';
+        this.currentLanguage = this.getDefaultLanguage();
         this.translations = {};
         this.loadingPromise = null;
     }
+    
+    getDefaultLanguage() {
+        // 1. 先檢查本地儲存的設定
+        const savedLanguage = localStorage.getItem('language');
+        if (savedLanguage && ['zh-TW', 'zh-CN', 'en'].includes(savedLanguage)) {
+            console.log('🌐 使用儲存的語言設定:', savedLanguage);
+            return savedLanguage;
+        }
+        
+        // 2. 檢查瀏覽器語言
+        const browserLang = navigator.language || navigator.userLanguage;
+        console.log('🌐 瀏覽器語言:', browserLang);
+        
+        if (browserLang.startsWith('zh-TW') || browserLang.includes('Hant')) {
+            console.log('🌐 偵測到繁體中文環境');
+            return 'zh-TW';
+        }
+        if (browserLang.startsWith('zh') || browserLang.includes('Hans')) {
+            console.log('🌐 偵測到簡體中文環境');
+            return 'zh-CN';
+        }
+        if (browserLang.startsWith('en')) {
+            console.log('🌐 偵測到英文環境');
+            return 'en';
+        }
+        
+        // 3. 預設使用繁體中文
+        console.log('🌐 使用預設語言: zh-TW');
+        return 'zh-TW';
+    }
 
     async init() {
         console.log(`i18nManager 使用預設語言: ${this.currentLanguage}`);
@@ -163,6 +193,16 @@ class I18nManager {
             }
         });
 
+        // 翻譯有 data-i18n-aria-label 屬性的元素
+        const ariaLabelElements = document.querySelectorAll('[data-i18n-aria-label]');
+        ariaLabelElements.forEach(element => {
+            const key = element.getAttribute('data-i18n-aria-label');
+            const translation = this.t(key);
+            if (translation && translation !== key) {
+                element.setAttribute('aria-label', translation);
+            }
+        });
+
         // 更新動態內容
         this.updateDynamicContent();
 
@@ -290,31 +330,18 @@ class I18nManager {
         // 設定頁籤的下拉選擇器
         const selector = document.getElementById('settingsLanguageSelect');
         if (selector) {
-            // 設置當前值
+            // 只設置當前值，不綁定事件（讓 SettingsManager 統一處理）
             selector.value = this.currentLanguage;
             console.log(`🔧 setupLanguageSelectors: 設置 select.value = ${this.currentLanguage}`);
-
-            // 移除舊的事件監聽器（如果存在）
-            if (selector._i18nChangeHandler) {
-                selector.removeEventListener('change', selector._i18nChangeHandler);
-            }
-
-            // 添加新的事件監聽器 - 通過 SettingsManager 統一管理
-            selector._i18nChangeHandler = (e) => {
-                console.log(`🔄 i18n select change event: ${e.target.value}`);
-                if (window.feedbackApp && window.feedbackApp.settingsManager) {
-                    window.feedbackApp.settingsManager.set('language', e.target.value);
-                } else {
-                    this.setLanguage(e.target.value);
-                }
-            };
-            selector.addEventListener('change', selector._i18nChangeHandler);
+            
+            // 不再綁定事件監聽器，避免與 SettingsManager 衝突
+            // 事件處理完全交由 SettingsManager 負責
         }
 
         // 新版現代化語言選擇器
         const languageOptions = document.querySelectorAll('.language-option');
         if (languageOptions.length > 0) {
-            // 設置當前語言的活躍狀態和點擊事件
+            // 只設置當前語言的活躍狀態，不綁定事件
             languageOptions.forEach(option => {
                 const lang = option.getAttribute('data-lang');
                 if (lang === this.currentLanguage) {
@@ -322,20 +349,8 @@ class I18nManager {
                 } else {
                     option.classList.remove('active');
                 }
-
-                // 移除舊的事件監聽器（如果存在）
-                option.removeEventListener('click', option._languageClickHandler);
-
-                // 添加新的點擊事件監聽器 - 通過 SettingsManager 統一管理
-                option._languageClickHandler = () => {
-                    if (window.feedbackApp && window.feedbackApp.settingsManager) {
-                        window.feedbackApp.settingsManager.set('language', lang);
-                    } else {
-                        this.setLanguage(lang);
-                    }
-                };
-                option.addEventListener('click', option._languageClickHandler);
             });
+            // 事件監聽器由 SettingsManager 統一處理，避免重複綁定
         }
     }
 
diff --git a/src/mcp_feedback_enhanced/web/static/js/modules/audio/audio-manager.js b/src/mcp_feedback_enhanced/web/static/js/modules/audio/audio-manager.js
index dd6f988..2112f92 100644
--- a/src/mcp_feedback_enhanced/web/static/js/modules/audio/audio-manager.js
+++ b/src/mcp_feedback_enhanced/web/static/js/modules/audio/audio-manager.js
@@ -591,7 +591,7 @@
         // 可以在這裡添加 UI 通知邏輯
         if (window.MCPFeedback && window.MCPFeedback.Utils && window.MCPFeedback.Utils.showMessage) {
             const message = window.i18nManager ?
-                window.i18nManager.t('audio.autoplayBlocked', '瀏覽器阻止音效自動播放，請點擊頁面以啟用音效通知') :
+                window.i18nManager.t('notification.autoplayBlocked', '瀏覽器阻止音效自動播放，請點擊頁面以啟用音效通知') :
                 '瀏覽器阻止音效自動播放，請點擊頁面以啟用音效通知';
             window.MCPFeedback.Utils.showMessage(message, 'info');
         }
diff --git a/src/mcp_feedback_enhanced/web/static/js/modules/audio/audio-settings-ui.js b/src/mcp_feedback_enhanced/web/static/js/modules/audio/audio-settings-ui.js
index 587a95d..cb10e17 100644
--- a/src/mcp_feedback_enhanced/web/static/js/modules/audio/audio-settings-ui.js
+++ b/src/mcp_feedback_enhanced/web/static/js/modules/audio/audio-settings-ui.js
@@ -85,13 +85,11 @@
                     <!-- 啟用開關 -->
                     <div class="setting-item">
                         <div class="setting-info">
-                            <div class="setting-label" data-i18n="audio.notification.enabled">啟用音效通知</div>
-                            <div class="setting-description" data-i18n="audio.notification.enabledDesc">
-                                啟用後將在有新會話更新時播放音效通知
-                            </div>
+                            <div class="setting-label" data-i18n="audio.notification.enabled"></div>
+                            <div class="setting-description" data-i18n="audio.notification.enabledDesc"></div>
                         </div>
                         <div class="setting-control">
-                            <button type="button" id="audioNotificationEnabled" class="toggle-btn" aria-label="切換音效通知">
+                            <button type="button" id="audioNotificationEnabled" class="toggle-btn" data-i18n-aria-label="aria.toggleAudioNotification">
                                 <span class="toggle-slider"></span>
                             </button>
                         </div>
@@ -668,6 +666,16 @@
             }
         });
 
+        // 對有 data-i18n-aria-label 屬性的元素應用翻譯
+        const ariaLabelElements = this.container.querySelectorAll('[data-i18n-aria-label]');
+        ariaLabelElements.forEach(element => {
+            const key = element.getAttribute('data-i18n-aria-label');
+            const translation = this.t(key);
+            if (translation && translation !== key) {
+                element.setAttribute('aria-label', translation);
+            }
+        });
+
         console.log('🌐 AudioSettingsUI 初始翻譯已應用');
     };
 
diff --git a/src/mcp_feedback_enhanced/web/static/js/modules/constants/message-codes.js b/src/mcp_feedback_enhanced/web/static/js/modules/constants/message-codes.js
new file mode 100644
index 0000000..daf2937
--- /dev/null
+++ b/src/mcp_feedback_enhanced/web/static/js/modules/constants/message-codes.js
@@ -0,0 +1,168 @@
+/**
+ * MCP Feedback Enhanced - 訊息代碼常量
+ * ====================================
+ * 
+ * 定義所有系統訊息的標準代碼，用於國際化支援
+ */
+
+(function() {
+    'use strict';
+
+    // 確保命名空間存在
+    window.MCPFeedback = window.MCPFeedback || {};
+    window.MCPFeedback.Constants = window.MCPFeedback.Constants || {};
+
+    /**
+     * 訊息代碼枚舉
+     * 所有系統訊息都應該使用這些代碼，而非硬編碼字串
+     */
+    const MessageCodes = {
+        // 系統狀態訊息
+        SYSTEM: {
+            CONNECTION_ESTABLISHED: 'system.connectionEstablished',
+            CONNECTION_LOST: 'system.connectionLost',
+            CONNECTION_RECONNECTING: 'system.connectionReconnecting',
+            CONNECTION_RECONNECTED: 'system.connectionReconnected',
+            CONNECTION_FAILED: 'system.connectionFailed',
+            WEBSOCKET_ERROR: 'system.websocketError'
+        },
+
+        // 會話相關訊息
+        SESSION: {
+            NO_ACTIVE_SESSION: 'session.noActiveSession',
+            SESSION_CREATED: 'session.created',
+            SESSION_UPDATED: 'session.updated',
+            SESSION_EXPIRED: 'session.expired',
+            SESSION_TIMEOUT: 'session.timeout',
+            SESSION_CLEANED: 'session.cleaned',
+            FEEDBACK_SUBMITTED: 'session.feedbackSubmitted',
+            USER_MESSAGE_RECORDED: 'session.userMessageRecorded',
+            HISTORY_SAVED: 'session.historySaved',
+            HISTORY_LOADED: 'session.historyLoaded',
+            MANUAL_CLEANUP: 'session.manualCleanup',
+            ERROR_CLEANUP: 'session.errorCleanup'
+        },
+
+        // 設定相關訊息
+        SETTINGS: {
+            SAVED: 'settings.saved',
+            LOADED: 'settings.loaded',
+            CLEARED: 'settings.cleared',
+            SAVE_FAILED: 'settings.saveFailed',
+            LOAD_FAILED: 'settings.loadFailed',
+            CLEAR_FAILED: 'settings.clearFailed',
+            INVALID_VALUE: 'settings.invalidValue',
+            LOG_LEVEL_UPDATED: 'settings.logLevelUpdated',
+            INVALID_LOG_LEVEL: 'settings.invalidLogLevel'
+        },
+
+        // 通知相關訊息
+        NOTIFICATION: {
+            AUTOPLAY_BLOCKED: 'notification.autoplayBlocked',
+            PERMISSION_DENIED: 'notification.permissionDenied',
+            PERMISSION_GRANTED: 'notification.permissionGranted',
+            TEST_SENT: 'notification.testSent',
+            SOUND_ENABLED: 'notification.soundEnabled',
+            SOUND_DISABLED: 'notification.soundDisabled'
+        },
+
+        // 檔案上傳訊息
+        FILE: {
+            UPLOAD_SUCCESS: 'file.uploadSuccess',
+            UPLOAD_FAILED: 'file.uploadFailed',
+            SIZE_TOO_LARGE: 'file.sizeTooLarge',
+            TYPE_NOT_SUPPORTED: 'file.typeNotSupported',
+            PROCESSING: 'file.processing',
+            REMOVED: 'file.removed'
+        },
+
+        // 提示詞相關訊息
+        PROMPT: {
+            SAVED: 'prompt.saved',
+            DELETED: 'prompt.deleted',
+            APPLIED: 'prompt.applied',
+            IMPORT_SUCCESS: 'prompt.importSuccess',
+            IMPORT_FAILED: 'prompt.importFailed',
+            EXPORT_SUCCESS: 'prompt.exportSuccess',
+            VALIDATION_FAILED: 'prompt.validationFailed'
+        },
+
+        // 錯誤訊息
+        ERROR: {
+            GENERIC: 'error.generic',
+            NETWORK: 'error.network',
+            SERVER: 'error.server',
+            TIMEOUT: 'error.timeout',
+            INVALID_INPUT: 'error.invalidInput',
+            OPERATION_FAILED: 'error.operationFailed'
+        },
+
+        // 命令執行訊息
+        COMMAND: {
+            EXECUTING: 'commandStatus.executing',
+            COMPLETED: 'commandStatus.completed',
+            FAILED: 'commandStatus.failed',
+            OUTPUT_RECEIVED: 'commandStatus.outputReceived',
+            INVALID_COMMAND: 'commandStatus.invalid',
+            ERROR: 'commandStatus.error'
+        }
+    };
+
+    /**
+     * 訊息嚴重程度
+     */
+    const MessageSeverity = {
+        INFO: 'info',
+        SUCCESS: 'success',
+        WARNING: 'warning',
+        ERROR: 'error'
+    };
+
+    /**
+     * 建立標準訊息物件
+     * @param {string} code - 訊息代碼
+     * @param {Object} params - 動態參數
+     * @param {string} severity - 嚴重程度
+     * @returns {Object} 標準訊息物件
+     */
+    function createMessage(code, params = {}, severity = MessageSeverity.INFO) {
+        return {
+            type: 'notification',
+            code: code,
+            params: params,
+            severity: severity,
+            timestamp: Date.now()
+        };
+    }
+
+    /**
+     * 快捷方法：建立成功訊息
+     */
+    function createSuccessMessage(code, params = {}) {
+        return createMessage(code, params, MessageSeverity.SUCCESS);
+    }
+
+    /**
+     * 快捷方法：建立錯誤訊息
+     */
+    function createErrorMessage(code, params = {}) {
+        return createMessage(code, params, MessageSeverity.ERROR);
+    }
+
+    /**
+     * 快捷方法：建立警告訊息
+     */
+    function createWarningMessage(code, params = {}) {
+        return createMessage(code, params, MessageSeverity.WARNING);
+    }
+
+    // 匯出到全域命名空間
+    window.MCPFeedback.Constants.MessageCodes = MessageCodes;
+    window.MCPFeedback.Constants.MessageSeverity = MessageSeverity;
+    window.MCPFeedback.Constants.createMessage = createMessage;
+    window.MCPFeedback.Constants.createSuccessMessage = createSuccessMessage;
+    window.MCPFeedback.Constants.createErrorMessage = createErrorMessage;
+    window.MCPFeedback.Constants.createWarningMessage = createWarningMessage;
+
+    console.log('📋 訊息代碼常量載入完成');
+})();
\ No newline at end of file
diff --git a/src/mcp_feedback_enhanced/web/static/js/modules/file-upload-manager.js b/src/mcp_feedback_enhanced/web/static/js/modules/file-upload-manager.js
index a7b3159..c765286 100644
--- a/src/mcp_feedback_enhanced/web/static/js/modules/file-upload-manager.js
+++ b/src/mcp_feedback_enhanced/web/static/js/modules/file-upload-manager.js
@@ -289,14 +289,23 @@
             if (this.maxFileSize > 0 && file.size > this.maxFileSize) {
                 const sizeLimit = this.formatFileSize(this.maxFileSize);
                 console.warn('⚠️ 檔案過大:', file.name, '超過限制', sizeLimit);
-                this.showMessage('圖片大小超過限制 (' + sizeLimit + '): ' + file.name, 'warning');
+                const message = window.i18nManager ?
+                    window.i18nManager.t('fileUpload.fileSizeExceeded', {
+                        limit: sizeLimit,
+                        filename: file.name
+                    }) :
+                    '圖片大小超過限制 (' + sizeLimit + '): ' + file.name;
+                this.showMessage(message, 'warning');
                 continue;
             }
 
             // 檢查檔案數量限制
             if (this.files.length + validFiles.length >= this.maxFiles) {
                 console.warn('⚠️ 檔案數量超過限制:', this.maxFiles);
-                this.showMessage('最多只能上傳 ' + this.maxFiles + ' 個檔案', 'warning');
+                const message = window.i18nManager ?
+                    window.i18nManager.t('fileUpload.maxFilesExceeded', { maxFiles: this.maxFiles }) :
+                    '最多只能上傳 ' + this.maxFiles + ' 個檔案';
+                this.showMessage(message, 'warning');
                 break;
             }
 
@@ -340,7 +349,10 @@
             })
             .catch(function(error) {
                 console.error('❌ 檔案處理失敗:', error);
-                self.showMessage('檔案處理失敗，請重試', 'error');
+                const message = window.i18nManager ?
+                    window.i18nManager.t('fileUpload.processingFailed', '檔案處理失敗，請重試') :
+                    '檔案處理失敗，請重試';
+                self.showMessage(message, 'error');
             });
     };
 
diff --git a/src/mcp_feedback_enhanced/web/static/js/modules/logger.js b/src/mcp_feedback_enhanced/web/static/js/modules/logger.js
index 4ea9dc6..8af2ed9 100644
--- a/src/mcp_feedback_enhanced/web/static/js/modules/logger.js
+++ b/src/mcp_feedback_enhanced/web/static/js/modules/logger.js
@@ -322,7 +322,8 @@
 
     // 從 API 載入日誌等級
     function loadLogLevelFromAPI() {
-        fetch('/api/log-level')
+        const lang = window.i18nManager ? window.i18nManager.getCurrentLanguage() : 'zh-TW';
+        fetch('/api/log-level?lang=' + lang)
             .then(function(response) {
                 if (response.ok) {
                     return response.json();
@@ -343,7 +344,8 @@
 
     // 保存日誌等級到 API
     function saveLogLevelToAPI(logLevel) {
-        fetch('/api/log-level', {
+        const lang = window.i18nManager ? window.i18nManager.getCurrentLanguage() : 'zh-TW';
+        fetch('/api/log-level?lang=' + lang, {
             method: 'POST',
             headers: {
                 'Content-Type': 'application/json',
@@ -360,6 +362,11 @@
         })
         .then(function(data) {
             console.log('📋 日誌等級已保存:', data.logLevel);
+            // 處理訊息代碼
+            if (data.messageCode && window.i18nManager) {
+                const message = window.i18nManager.t(data.messageCode, data.params);
+                console.log('伺服器回應:', message);
+            }
         })
         .catch(function(error) {
             console.warn('⚠️ 保存日誌等級失敗:', error);
diff --git a/src/mcp_feedback_enhanced/web/static/js/modules/notification/notification-settings.js b/src/mcp_feedback_enhanced/web/static/js/modules/notification/notification-settings.js
index 9656cb5..099f54c 100644
--- a/src/mcp_feedback_enhanced/web/static/js/modules/notification/notification-settings.js
+++ b/src/mcp_feedback_enhanced/web/static/js/modules/notification/notification-settings.js
@@ -55,6 +55,11 @@
         this.setupEventListeners();
         this.updateUI();
 
+        // 應用翻譯到動態生成的內容
+        if (window.i18nManager) {
+            window.i18nManager.applyTranslations();
+        }
+
         console.log('✅ NotificationSettings 初始化完成');
     };
 
@@ -66,17 +71,15 @@
             <!-- 啟用開關 -->
             <div class="setting-item">
                 <div class="setting-info">
-                    <div class="setting-label" data-i18n="notification.settingLabel">瀏覽器通知</div>
-                    <div class="setting-description" data-i18n="notification.description">
-                        新會話建立時通知（僅在背景執行時）
-                    </div>
+                    <div class="setting-label" data-i18n="notification.settingLabel"></div>
+                    <div class="setting-description" data-i18n="notification.description"></div>
                     <!-- 權限狀態 -->
                     <div id="permissionStatus" class="permission-status">
                         <!-- 動態更新 -->
                     </div>
                 </div>
                 <div class="setting-control">
-                    <button type="button" id="notificationToggle" class="toggle-btn" aria-label="切換通知">
+                    <button type="button" id="notificationToggle" class="toggle-btn" data-i18n-aria-label="aria.toggleNotification">
                         <span class="toggle-slider"></span>
                     </button>
                 </div>
@@ -85,25 +88,25 @@
             <!-- 通知觸發情境 -->
             <div class="setting-item notification-trigger" style="display: none;">
                 <div class="setting-info">
-                    <div class="setting-label" data-i18n="notification.triggerTitle">通知觸發情境</div>
-                    <div class="setting-description" data-i18n="notification.triggerDescription">選擇何時接收通知</div>
+                    <div class="setting-label" data-i18n="notification.triggerTitle"></div>
+                    <div class="setting-description" data-i18n="notification.triggerDescription"></div>
                 </div>
                 <div class="trigger-options">
                     <label class="radio-option">
                         <input type="radio" name="notificationTrigger" value="focusLost" checked>
-                        <span data-i18n="notification.trigger.focusLost">視窗失去焦點時（切換到其他應用程式）</span>
+                        <span data-i18n="notification.trigger.focusLost"></span>
                     </label>
                     <label class="radio-option">
                         <input type="radio" name="notificationTrigger" value="tabSwitch">
-                        <span data-i18n="notification.trigger.tabSwitch">切換到其他標籤頁時</span>
+                        <span data-i18n="notification.trigger.tabSwitch"></span>
                     </label>
                     <label class="radio-option">
                         <input type="radio" name="notificationTrigger" value="background">
-                        <span data-i18n="notification.trigger.background">視窗最小化或隱藏時</span>
+                        <span data-i18n="notification.trigger.background"></span>
                     </label>
                     <label class="radio-option">
                         <input type="radio" name="notificationTrigger" value="always">
-                        <span data-i18n="notification.trigger.always">總是通知（包括前景）</span>
+                        <span data-i18n="notification.trigger.always"></span>
                     </label>
                 </div>
             </div>
@@ -111,12 +114,12 @@
             <!-- 測試按鈕 -->
             <div class="setting-item notification-actions" style="display: none;">
                 <div class="setting-info">
-                    <div class="setting-label" data-i18n="notification.testTitle">測試通知</div>
-                    <div class="setting-description" data-i18n="notification.testDescription">發送測試通知以確認功能正常</div>
+                    <div class="setting-label" data-i18n="notification.testTitle"></div>
+                    <div class="setting-description" data-i18n="notification.testDescription"></div>
                 </div>
                 <div class="setting-control">
                     <button type="button" id="testNotification" class="btn-primary">
-                        <span data-i18n="notification.test">發送測試通知</span>
+                        <span data-i18n="notification.test"></span>
                     </button>
                 </div>
             </div>
@@ -261,7 +264,7 @@
         const settings = this.notificationManager.getSettings();
         
         if (!settings.browserSupported) {
-            this.statusDiv.innerHTML = `<span data-i18n="notification.notSupported">⚠️ 您的瀏覽器不支援通知功能</span>`;
+            this.statusDiv.innerHTML = `<span data-i18n="notification.notSupported"></span>`;
             this.statusDiv.className = 'permission-status status-unsupported';
             this.toggle.disabled = true;
             return;
diff --git a/src/mcp_feedback_enhanced/web/static/js/modules/session-manager.js b/src/mcp_feedback_enhanced/web/static/js/modules/session-manager.js
index d8a2c6b..cb3f115 100644
--- a/src/mcp_feedback_enhanced/web/static/js/modules/session-manager.js
+++ b/src/mcp_feedback_enhanced/web/static/js/modules/session-manager.js
@@ -370,7 +370,10 @@
         const currentSession = this.dataManager.getCurrentSession();
 
         if (!currentSession) {
-            this.showMessage('目前沒有活躍的會話數據', 'warning');
+            const message = window.i18nManager ? 
+                window.i18nManager.t('sessionHistory.noActiveSession', '目前沒有活躍的會話數據') : 
+                '目前沒有活躍的會話數據';
+            this.showMessage(message, 'warning');
             return;
         }
 
@@ -390,7 +393,10 @@
         if (sessionData) {
             this.detailsModal.showSessionDetails(sessionData);
         } else {
-            this.showMessage('找不到會話資料', 'error');
+            const message = window.i18nManager ? 
+                window.i18nManager.t('sessionHistory.sessionNotFound', '找不到會話資料') : 
+                '找不到會話資料';
+            this.showMessage(message, 'error');
         }
     };
 
@@ -595,7 +601,10 @@
         } catch (error) {
             console.error('📋 匯出會話歷史失敗:', error);
             if (window.MCPFeedback && window.MCPFeedback.Utils && window.MCPFeedback.Utils.showMessage) {
-                window.MCPFeedback.Utils.showMessage('匯出失敗: ' + error.message, 'error');
+                const message = window.i18nManager ?
+                    window.i18nManager.t('sessionHistory.management.exportFailed', { error: error.message }) :
+                    '匯出失敗: ' + error.message;
+                window.MCPFeedback.Utils.showMessage(message, 'error');
             }
         }
     };
@@ -623,7 +632,10 @@
         } catch (error) {
             console.error('📋 匯出單一會話失敗:', error);
             if (window.MCPFeedback && window.MCPFeedback.Utils && window.MCPFeedback.Utils.showMessage) {
-                window.MCPFeedback.Utils.showMessage('匯出失敗: ' + error.message, 'error');
+                const message = window.i18nManager ?
+                    window.i18nManager.t('sessionHistory.management.exportFailed', { error: error.message }) :
+                    '匯出失敗: ' + error.message;
+                window.MCPFeedback.Utils.showMessage(message, 'error');
             }
         }
     };
@@ -659,7 +671,10 @@
         } catch (error) {
             console.error('📋 清空會話歷史失敗:', error);
             if (window.MCPFeedback && window.MCPFeedback.Utils && window.MCPFeedback.Utils.showMessage) {
-                window.MCPFeedback.Utils.showMessage('清空失敗: ' + error.message, 'error');
+                const errorMessage = window.i18nManager ?
+                    window.i18nManager.t('sessionHistory.management.clearFailed', { error: error.message }) :
+                    '清空失敗: ' + error.message;
+                window.MCPFeedback.Utils.showMessage(errorMessage, 'error');
             }
         }
     };
@@ -690,11 +705,17 @@
                     '用戶訊息記錄已清空';
                 this.showMessage(successMessage, 'success');
             } else {
-                this.showMessage('清空失敗', 'error');
+                const errorMessage = window.i18nManager ?
+                    window.i18nManager.t('sessionHistory.management.clearFailedGeneric', '清空失敗') :
+                    '清空失敗';
+                this.showMessage(errorMessage, 'error');
             }
         } catch (error) {
             console.error('📋 清空用戶訊息記錄失敗:', error);
-            this.showMessage('清空失敗: ' + error.message, 'error');
+            const errorMessage = window.i18nManager ?
+                window.i18nManager.t('sessionHistory.management.clearFailed', { error: error.message }) :
+                '清空失敗: ' + error.message;
+            this.showMessage(errorMessage, 'error');
         }
     };
 
@@ -752,15 +773,24 @@
         try {
             const currentSession = this.dataManager.getCurrentSession();
             if (!currentSession) {
-                this.showMessage('没有当前会话数据', 'error');
+                const message = window.i18nManager ?
+                    window.i18nManager.t('sessionHistory.currentSession.noData', '沒有當前會話數據') :
+                    '沒有當前會話數據';
+                this.showMessage(message, 'error');
                 return;
             }
 
             const content = this.formatCurrentSessionContent(currentSession);
-            this.copyToClipboard(content, '当前会话内容已复制到剪贴板');
+            const successMessage = window.i18nManager ?
+                window.i18nManager.t('sessionHistory.currentSession.copySuccess', '當前會話內容已複製到剪貼板') :
+                '當前會話內容已複製到剪貼板';
+            this.copyToClipboard(content, successMessage);
         } catch (error) {
             console.error('复制当前会话内容失败:', error);
-            this.showMessage('复制失败，请重试', 'error');
+            const message = window.i18nManager ?
+                window.i18nManager.t('sessionHistory.currentSession.copyFailed', '複製失敗，請重試') :
+                '複製失敗，請重試';
+            this.showMessage(message, 'error');
         }
     };
 
@@ -774,7 +804,10 @@
         try {
             if (!this.dataManager) {
                 console.log('📝 dataManager 不存在，尝试其他方式获取数据');
-                this.showMessage('数据管理器未初始化', 'error');
+                const message = window.i18nManager ?
+                    window.i18nManager.t('sessionHistory.currentSession.dataManagerNotInit', '數據管理器未初始化') :
+                    '數據管理器未初始化';
+                this.showMessage(message, 'error');
                 return;
             }
 
@@ -783,7 +816,10 @@
 
             if (!currentSession) {
                 console.log('📝 没有当前会话数据');
-                this.showMessage('当前会话没有数据', 'warning');
+                const message = window.i18nManager ?
+                    window.i18nManager.t('sessionHistory.currentSession.noData', '當前會話沒有數據') :
+                    '當前會話沒有數據';
+                this.showMessage(message, 'warning');
                 return;
             }
 
@@ -792,7 +828,10 @@
 
             if (!currentSession.user_messages || currentSession.user_messages.length === 0) {
                 console.log('📝 没有用户消息记录');
-                this.showMessage('当前会话没有用户消息记录', 'warning');
+                const message = window.i18nManager ?
+                    window.i18nManager.t('sessionHistory.currentSession.noUserMessages', '當前會話沒有用戶消息記錄') :
+                    '當前會話沒有用戶消息記錄';
+                this.showMessage(message, 'warning');
                 return;
             }
 
@@ -804,11 +843,17 @@
             console.log('📝 格式化后的内容长度:', content.length);
             console.log('📝 格式化后的内容预览:', content.substring(0, 200));
 
-            this.copyToClipboard(content, '当前用户内容已复制到剪贴板');
+            const successMessage = window.i18nManager ?
+                window.i18nManager.t('sessionHistory.currentSession.userContentCopySuccess', '當前用戶內容已複製到剪貼板') :
+                '當前用戶內容已複製到剪貼板';
+            this.copyToClipboard(content, successMessage);
         } catch (error) {
             console.error('📝 复制当前用户内容失败:', error);
             console.error('📝 错误堆栈:', error.stack);
-            this.showMessage('复制失败，请重试', 'error');
+            const message = window.i18nManager ?
+                window.i18nManager.t('sessionHistory.currentSession.copyFailed', '複製失敗，請重試') :
+                '複製失敗，請重試';
+            this.showMessage(message, 'error');
         }
     };
 
@@ -959,7 +1004,10 @@
             this.showMessage(successMessage, 'success');
         } catch (err) {
             console.error('降级复制失败:', err);
-            this.showMessage('复制失败，请手动复制', 'error');
+            const message = window.i18nManager ?
+                window.i18nManager.t('sessionHistory.currentSession.copyFailedManual', '複製失敗，請手動複製') :
+                '複製失敗，請手動複製';
+            this.showMessage(message, 'error');
         } finally {
             document.body.removeChild(textArea);
         }
diff --git a/src/mcp_feedback_enhanced/web/static/js/modules/session/session-data-manager.js b/src/mcp_feedback_enhanced/web/static/js/modules/session/session-data-manager.js
index 61b1906..e14bec1 100644
--- a/src/mcp_feedback_enhanced/web/static/js/modules/session/session-data-manager.js
+++ b/src/mcp_feedback_enhanced/web/static/js/modules/session/session-data-manager.js
@@ -327,7 +327,8 @@
      * 發送用戶消息到服務器端
      */
     SessionDataManager.prototype.sendUserMessageToServer = function(userMessage) {
-        fetch('/api/add-user-message', {
+        const lang = window.i18nManager ? window.i18nManager.getCurrentLanguage() : 'zh-TW';
+        fetch('/api/add-user-message?lang=' + lang, {
             method: 'POST',
             headers: {
                 'Content-Type': 'application/json'
@@ -633,7 +634,8 @@
         const self = this;
 
         // 首先嘗試獲取實時會話狀態
-        fetch('/api/all-sessions')
+        const lang = window.i18nManager ? window.i18nManager.getCurrentLanguage() : 'zh-TW';
+        fetch('/api/all-sessions?lang=' + lang)
             .then(function(response) {
                 if (response.ok) {
                     return response.json();
@@ -677,7 +679,8 @@
     SessionDataManager.prototype.loadFromHistoryFile = function() {
         const self = this;
 
-        fetch('/api/load-session-history')
+        const lang = window.i18nManager ? window.i18nManager.getCurrentLanguage() : 'zh-TW';
+        fetch('/api/load-session-history?lang=' + lang)
             .then(function(response) {
                 if (response.ok) {
                     return response.json();
@@ -775,7 +778,8 @@
             lastCleanup: TimeUtils.getCurrentTimestamp()
         };
 
-        fetch('/api/save-session-history', {
+        const lang = window.i18nManager ? window.i18nManager.getCurrentLanguage() : 'zh-TW';
+        fetch('/api/save-session-history?lang=' + lang, {
             method: 'POST',
             headers: {
                 'Content-Type': 'application/json',
@@ -791,7 +795,12 @@
             }
         })
         .then(function(result) {
-            console.log('📊 會話快照保存回應:', result.message);
+            if (result.messageCode && window.i18nManager) {
+                const message = window.i18nManager.t(result.messageCode, result.params);
+                console.log('📊 會話快照保存回應:', message);
+            } else {
+                console.log('📊 會話快照保存回應:', result.message);
+            }
         })
         .catch(function(error) {
             console.error('📊 保存會話快照到伺服器失敗:', error);
@@ -807,7 +816,8 @@
             lastCleanup: TimeUtils.getCurrentTimestamp()
         };
 
-        fetch('/api/save-session-history', {
+        const lang = window.i18nManager ? window.i18nManager.getCurrentLanguage() : 'zh-TW';
+        fetch('/api/save-session-history?lang=' + lang, {
             method: 'POST',
             headers: {
                 'Content-Type': 'application/json',
@@ -823,7 +833,12 @@
             }
         })
         .then(function(result) {
-            console.log('📊 伺服器保存回應:', result.message);
+            if (result.messageCode && window.i18nManager) {
+                const message = window.i18nManager.t(result.messageCode, result.params);
+                console.log('📊 伺服器保存回應:', message);
+            } else {
+                console.log('📊 伺服器保存回應:', result.message);
+            }
         })
         .catch(function(error) {
             console.error('📊 保存會話歷史到伺服器失敗:', error);
diff --git a/src/mcp_feedback_enhanced/web/static/js/modules/settings-manager.js b/src/mcp_feedback_enhanced/web/static/js/modules/settings-manager.js
index ce26c06..5077116 100644
--- a/src/mcp_feedback_enhanced/web/static/js/modules/settings-manager.js
+++ b/src/mcp_feedback_enhanced/web/static/js/modules/settings-manager.js
@@ -23,11 +23,14 @@
     function SettingsManager(options) {
         options = options || {};
         
+        // 從 i18nManager 獲取當前語言作為預設值
+        const defaultLanguage = window.i18nManager ? window.i18nManager.getCurrentLanguage() : 'zh-TW';
+        
         // 預設設定
         this.defaultSettings = {
             layoutMode: 'combined-vertical',
             autoClose: false,
-            language: 'zh-TW',
+            language: defaultLanguage,  // 使用 i18nManager 的當前語言
             imageSizeLimit: 0,
             enableBase64Detail: false,
             // 移除 activeTab - 頁籤切換無需持久化
@@ -80,6 +83,17 @@
                         console.log('沒有找到設定，使用預設值');
                         self.currentSettings = Utils.deepClone(self.defaultSettings);
                     }
+                    
+                    // 同步語言設定到 i18nManager
+                    if (self.currentSettings.language && window.i18nManager) {
+                        const currentI18nLanguage = window.i18nManager.getCurrentLanguage();
+                        if (self.currentSettings.language !== currentI18nLanguage) {
+                            console.log('🔧 SettingsManager.loadSettings: 同步語言設定到 i18nManager');
+                            console.log('  從:', currentI18nLanguage, '到:', self.currentSettings.language);
+                            window.i18nManager.setLanguage(self.currentSettings.language);
+                        }
+                    }
+                    
                     resolve(self.currentSettings);
                 })
                 .catch(function(error) {
@@ -94,7 +108,8 @@
      * 從伺服器載入設定
      */
     SettingsManager.prototype.loadFromServer = function() {
-        return fetch('/api/load-settings')
+        const lang = window.i18nManager ? window.i18nManager.getCurrentLanguage() : 'zh-TW';
+        return fetch('/api/load-settings?lang=' + lang)
             .then(function(response) {
                 if (response.ok) {
                     return response.json();
@@ -146,7 +161,8 @@
     SettingsManager.prototype._performServerSave = function() {
         const self = this;
 
-        fetch('/api/save-settings', {
+        const lang = window.i18nManager ? window.i18nManager.getCurrentLanguage() : 'zh-TW';
+        fetch('/api/save-settings?lang=' + lang, {
             method: 'POST',
             headers: {
                 'Content-Type': 'application/json',
@@ -154,10 +170,18 @@
             body: JSON.stringify(self.currentSettings)
         })
         .then(function(response) {
-            if (response.ok) {
+            return response.json();
+        })
+        .then(function(data) {
+            if (data.status === 'success') {
                 console.log('設定已即時同步到伺服器端');
+                // 處理訊息代碼
+                if (data.messageCode && window.i18nManager) {
+                    const message = window.i18nManager.t(data.messageCode, data.params);
+                    console.log('伺服器回應:', message);
+                }
             } else {
-                console.warn('同步設定到伺服器端失敗:', response.status);
+                console.warn('同步設定到伺服器端失敗:', data);
             }
         })
         .catch(function(error) {
@@ -239,15 +263,12 @@
      * 處理語言變更
      */
     SettingsManager.prototype.handleLanguageChange = function(newLanguage) {
-        console.log('語言設定變更: ' + newLanguage);
+        console.log('🔄 SettingsManager.handleLanguageChange: ' + newLanguage);
 
         // 通知國際化系統（統一由 SettingsManager 管理）
         if (window.i18nManager) {
-            // 直接設定語言，不觸發 i18nManager 的保存邏輯
-            window.i18nManager.currentLanguage = newLanguage;
-            window.i18nManager.applyTranslations();
-            window.i18nManager.setupLanguageSelectors();
-            document.documentElement.lang = newLanguage;
+            // 使用 setLanguage 方法確保正確更新
+            window.i18nManager.setLanguage(newLanguage);
         }
 
         // 延遲更新動態文字，確保 i18n 已經載入新語言
@@ -688,7 +709,10 @@
                 try {
                     // 如果要啟用自動提交，檢查是否已選擇提示詞
                     if (newValue && (!currentPromptId || currentPromptId === '')) {
-                        Utils.showMessage('請先選擇一個提示詞作為自動提交內容', Utils.CONSTANTS.MESSAGE_WARNING);
+                        const message = window.i18nManager ? 
+                            window.i18nManager.t('settingsUI.autoCommitNoPrompt', '請先選擇一個提示詞作為自動提交內容') : 
+                            '請先選擇一個提示詞作為自動提交內容';
+                        Utils.showMessage(message, Utils.CONSTANTS.MESSAGE_WARNING);
                         return;
                     }
 
diff --git a/src/mcp_feedback_enhanced/web/static/js/modules/ui-manager.js b/src/mcp_feedback_enhanced/web/static/js/modules/ui-manager.js
index 534b55d..d32c052 100644
--- a/src/mcp_feedback_enhanced/web/static/js/modules/ui-manager.js
+++ b/src/mcp_feedback_enhanced/web/static/js/modules/ui-manager.js
@@ -494,7 +494,9 @@
                 feedbackInput.value = '';
                 console.log('📝 已清空文字內容');
             }
-            feedbackInput.disabled = false;
+            // 只有在等待狀態才啟用輸入框
+            const canInput = this.feedbackState === Utils.CONSTANTS.FEEDBACK_WAITING;
+            feedbackInput.disabled = !canInput;
         }
 
         // 重新啟用提交按鈕
diff --git a/src/mcp_feedback_enhanced/web/static/js/modules/utils.js b/src/mcp_feedback_enhanced/web/static/js/modules/utils.js
index 00ef3ee..33baf5d 100644
--- a/src/mcp_feedback_enhanced/web/static/js/modules/utils.js
+++ b/src/mcp_feedback_enhanced/web/static/js/modules/utils.js
@@ -169,8 +169,12 @@
          * @returns {Promise<boolean>} 複製是否成功
          */
         copyToClipboard: function(text, successMessage, errorMessage) {
-            successMessage = successMessage || '已複製到剪貼板';
-            errorMessage = errorMessage || '複製失敗';
+            successMessage = successMessage || (window.i18nManager ? 
+                window.i18nManager.t('utils.copySuccess', '已複製到剪貼板') : 
+                '已複製到剪貼板');
+            errorMessage = errorMessage || (window.i18nManager ? 
+                window.i18nManager.t('utils.copyError', '複製失敗') : 
+                '複製失敗');
 
             return new Promise(function(resolve) {
                 if (navigator.clipboard && navigator.clipboard.writeText) {
@@ -262,7 +266,115 @@
          * @param {string} type - 訊息類型 (success, error, warning, info)
          * @param {number} duration - 顯示時間（毫秒）
          */
-        showMessage: function(message, type, duration) {
+        showMessage: function(messageOrCode, type, duration) {
+            // 處理訊息代碼物件
+            let actualMessage = messageOrCode;
+            let actualType = type || 'info';
+            
+            if (typeof messageOrCode === 'object' && messageOrCode.code) {
+                // 使用 i18n 系統翻譯訊息代碼
+                if (window.i18nManager) {
+                    actualMessage = window.i18nManager.t(messageOrCode.code, messageOrCode.params);
+                } else {
+                    // 改善 fallback 機制：提供基本的英文訊息
+                    actualMessage = this.getFallbackMessage(messageOrCode.code, messageOrCode.params);
+                }
+                // 使用訊息物件中的嚴重程度
+                actualType = messageOrCode.severity || type || 'info';
+            }
+            
+            // 呼叫內部顯示方法
+            return this._displayMessage(actualMessage, actualType, duration);
+        },
+        
+        /**
+         * 獲取 fallback 訊息
+         * 當 i18n 系統尚未載入時使用
+         * @param {string} code - 訊息代碼
+         * @param {Object} params - 參數
+         * @returns {string} fallback 訊息
+         */
+        getFallbackMessage: function(code, params) {
+            // 基本的 fallback 訊息對照表
+            const fallbackMessages = {
+                // 系統相關
+                'system.connectionEstablished': 'WebSocket connection established',
+                'system.connectionLost': 'WebSocket connection lost',
+                'system.connectionReconnecting': 'Reconnecting...',
+                'system.connectionReconnected': 'Reconnected',
+                'system.connectionFailed': 'Connection failed',
+                'system.websocketError': 'WebSocket error',
+                'system.websocketReady': 'WebSocket ready',
+                'system.memoryPressure': 'Memory pressure cleanup',
+                'system.shutdown': 'System shutdown',
+                'system.processKilled': 'Process killed',
+                'system.heartbeatStopped': 'Heartbeat stopped',
+                
+                // 會話相關
+                'session.noActiveSession': 'No active session',
+                'session.created': 'New session created',
+                'session.updated': 'Session updated',
+                'session.expired': 'Session expired',
+                'session.timeout': 'Session timed out',
+                'session.cleaned': 'Session cleaned',
+                'session.feedbackSubmitted': 'Feedback submitted successfully',
+                'session.userMessageRecorded': 'User message recorded',
+                'session.historySaved': 'Session history saved',
+                'session.historyLoaded': 'Session history loaded',
+                
+                // 設定相關
+                'settings.saved': 'Settings saved',
+                'settings.loaded': 'Settings loaded',
+                'settings.cleared': 'Settings cleared',
+                'settings.saveFailed': 'Save failed',
+                'settings.loadFailed': 'Load failed',
+                'settings.clearFailed': 'Clear failed',
+                'settings.setFailed': 'Set failed',
+                'settings.logLevelUpdated': 'Log level updated',
+                'settings.invalidLogLevel': 'Invalid log level',
+                
+                // 錯誤相關
+                'error.generic': 'An error occurred',
+                'error.userMessageFailed': 'Failed to add user message',
+                'error.getSessionsFailed': 'Failed to get sessions',
+                'error.getLogLevelFailed': 'Failed to get log level',
+                'error.command': 'Command execution error',
+                'error.resourceCleanup': 'Resource cleanup error',
+                'error.processing': 'Processing error',
+                
+                // 通知相關
+                'notification.autoplayBlocked': 'Browser blocked autoplay, click page to enable sound',
+                
+                // 預設訊息
+                'default': 'System message'
+            };
+            
+            // 嘗試獲取對應的 fallback 訊息
+            let message = fallbackMessages[code] || fallbackMessages['default'];
+            
+            // 處理參數替換（簡單版本）
+            if (params && typeof params === 'object') {
+                for (const key in params) {
+                    if (params.hasOwnProperty(key)) {
+                        const placeholder = '{{' + key + '}}';
+                        message = message.replace(placeholder, params[key]);
+                    }
+                }
+            }
+            
+            // 在開發模式下顯示警告
+            if (window.location.hostname === 'localhost' || window.location.hostname === '127.0.0.1') {
+                console.warn('[i18n] Fallback message used for:', code, '→', message);
+            }
+            
+            return message;
+        },
+        
+        /**
+         * 內部方法：實際顯示訊息
+         * @private
+         */
+        _displayMessage: function(message, type, duration) {
             type = type || 'info';
             duration = duration || 3000;
 
diff --git a/src/mcp_feedback_enhanced/web/static/js/modules/websocket-manager.js b/src/mcp_feedback_enhanced/web/static/js/modules/websocket-manager.js
index 703062e..c48d8c0 100644
--- a/src/mcp_feedback_enhanced/web/static/js/modules/websocket-manager.js
+++ b/src/mcp_feedback_enhanced/web/static/js/modules/websocket-manager.js
@@ -74,7 +74,10 @@
                 this.websocket = null;
             }
 
-            this.websocket = new WebSocket(wsUrl);
+            // 添加語言參數到 WebSocket URL
+            const language = window.i18nManager ? window.i18nManager.getCurrentLanguage() : 'zh-TW';
+            const wsUrlWithLang = wsUrl + (wsUrl.includes('?') ? '&' : '?') + 'lang=' + language;
+            this.websocket = new WebSocket(wsUrlWithLang);
             this.setupWebSocketEvents();
 
         } catch (error) {
@@ -261,6 +264,11 @@
                 console.log('WebSocket 連接確認');
                 this.connectionReady = true;
                 this.handleConnectionReady();
+                // 處理訊息代碼
+                if (data.messageCode && window.i18nManager) {
+                    const message = window.i18nManager.t(data.messageCode);
+                    Utils.showMessage(message, Utils.CONSTANTS.MESSAGE_SUCCESS);
+                }
                 break;
             case 'heartbeat_response':
                 this.handleHeartbeatResponse();
diff --git a/src/mcp_feedback_enhanced/web/templates/feedback.html b/src/mcp_feedback_enhanced/web/templates/feedback.html
index 18783df..eec4258 100644
--- a/src/mcp_feedback_enhanced/web/templates/feedback.html
+++ b/src/mcp_feedback_enhanced/web/templates/feedback.html
@@ -693,13 +693,13 @@
                 <!-- 介面設定卡片 -->
                 <div class="settings-card">
                     <div class="settings-card-header">
-                        <h3 class="settings-card-title" data-i18n="settings.interface">🎨 介面設定</h3>
+                        <h3 class="settings-card-title" data-i18n="settingsUI.interface">🎨 介面設定</h3>
                     </div>
                     <div class="settings-card-body">
                         <div class="setting-item">
                             <div class="setting-info">
-                                <div class="setting-label" data-i18n="settings.layoutMode">界面佈局模式</div>
-                                <div class="setting-description" data-i18n="settings.layoutModeDesc">
+                                <div class="setting-label" data-i18n="settingsUI.layoutMode">界面佈局模式</div>
+                                <div class="setting-description" data-i18n="settingsUI.layoutModeDesc">
                                     選擇 AI 摘要和回饋輸入的顯示方式
                                 </div>
                             </div>
@@ -707,15 +707,15 @@
                                 <div class="layout-option">
                                     <input type="radio" id="combinedVertical" name="layoutMode" value="combined-vertical" checked>
                                     <label for="combinedVertical">
-                                        <div class="layout-option-title" data-i18n="settings.combinedVertical">垂直布局</div>
-                                        <div class="layout-option-desc" data-i18n="settings.combinedVerticalDesc">AI 摘要在上，回饋輸入在下，摘要和回饋在同一頁面</div>
+                                        <div class="layout-option-title" data-i18n="settingsUI.combinedVertical">垂直布局</div>
+                                        <div class="layout-option-desc" data-i18n="settingsUI.combinedVerticalDesc">AI 摘要在上，回饋輸入在下，摘要和回饋在同一頁面</div>
                                     </label>
                                 </div>
                                 <div class="layout-option">
                                     <input type="radio" id="combinedHorizontal" name="layoutMode" value="combined-horizontal">
                                     <label for="combinedHorizontal">
-                                        <div class="layout-option-title" data-i18n="settings.combinedHorizontal">水平布局</div>
-                                        <div class="layout-option-desc" data-i18n="settings.combinedHorizontalDesc">AI 摘要在左，回饋輸入在右，增大摘要可視區域</div>
+                                        <div class="layout-option-title" data-i18n="settingsUI.combinedHorizontal">水平布局</div>
+                                        <div class="layout-option-desc" data-i18n="settingsUI.combinedHorizontalDesc">AI 摘要在左，回饋輸入在右，增大摘要可視區域</div>
                                     </label>
                                 </div>
                             </div>
@@ -729,13 +729,13 @@
                 <!-- 語言設定卡片 -->
                 <div class="settings-card">
                     <div class="settings-card-header">
-                        <h3 class="settings-card-title" data-i18n="settings.language">🌍 語言設定</h3>
+                        <h3 class="settings-card-title" data-i18n="settingsUI.language">🌍 語言設定</h3>
                     </div>
                     <div class="settings-card-body">
                         <div class="setting-item">
                             <div class="setting-info">
-                                <div class="setting-label" data-i18n="settings.currentLanguage">當前語言</div>
-                                <div class="setting-description" data-i18n="settings.languageDesc">
+                                <div class="setting-label" data-i18n="settingsUI.currentLanguage">當前語言</div>
+                                <div class="setting-description" data-i18n="settingsUI.languageDesc">
                                     選擇界面顯示語言
                                 </div>
                             </div>
@@ -804,7 +804,7 @@
                                 </div>
                             </div>
                             <div class="setting-control">
-                                <button type="button" id="autoSubmitToggle" class="toggle-btn" aria-label="切換自動提交">
+                                <button type="button" id="autoSubmitToggle" class="toggle-btn" data-i18n-aria-label="aria.toggleAutoSubmit">
                                     <span class="toggle-slider"></span>
                                 </button>
                             </div>
@@ -962,18 +962,18 @@
                 <!-- 重置設定卡片 -->
                 <div class="settings-card">
                     <div class="settings-card-header">
-                        <h3 class="settings-card-title" data-i18n="settings.advanced">🔧 進階設定</h3>
+                        <h3 class="settings-card-title" data-i18n="settingsUI.advanced">🔧 進階設定</h3>
                     </div>
                     <div class="settings-card-body">
                         <div class="setting-item" style="border-bottom: none;">
                             <div class="setting-info">
-                                <div class="setting-label" data-i18n="settings.reset">重置設定</div>
-                                <div class="setting-description" data-i18n="settings.resetDesc">
+                                <div class="setting-label" data-i18n="settingsUI.reset">重置設定</div>
+                                <div class="setting-description" data-i18n="settingsUI.resetDesc">
                                     清除所有已保存的設定，恢復到預設狀態
                                 </div>
                             </div>
                             <button id="resetSettingsBtn" class="btn btn-secondary" style="font-size: 12px; padding: 6px 16px;">
-                                <span data-i18n="settings.reset">重置設定</span>
+                                <span data-i18n="settingsUI.reset">重置設定</span>
                             </button>
                         </div>
                     </div>