diff --git a/ProjectVG.Api/Models/Chat/Request/ChatRequest.cs b/ProjectVG.Api/Models/Chat/Request/ChatRequest.cs
index fd73f18..4b6a777 100644
--- a/ProjectVG.Api/Models/Chat/Request/ChatRequest.cs
+++ b/ProjectVG.Api/Models/Chat/Request/ChatRequest.cs
@@ -26,6 +26,9 @@ public class ChatRequest
         [JsonPropertyName("instruction")]
         public string? Instruction { get; set; }
 
+        [JsonPropertyName("use_tts")]
+        public bool UseTTS { get; set; } = true;
+
         public ProcessChatCommand ToProcessChatCommand()
         {
             return new ProcessChatCommand
@@ -36,7 +39,8 @@ public ProcessChatCommand ToProcessChatCommand()
                 RequestedAt = this.RequestedAt,
                 Action = this.Action,
                 Instruction = this.Instruction,
-                UserId = this.UserId
+                UserId = this.UserId,
+                UseTTS = this.UseTTS
             };
         }
     }
diff --git a/ProjectVG.Application/ApplicationServiceCollectionExtensions.cs b/ProjectVG.Application/ApplicationServiceCollectionExtensions.cs
index 5859708..834271d 100644
--- a/ProjectVG.Application/ApplicationServiceCollectionExtensions.cs
+++ b/ProjectVG.Application/ApplicationServiceCollectionExtensions.cs
@@ -2,9 +2,11 @@
 using ProjectVG.Application.Services.Character;
 using ProjectVG.Application.Services.User;
 using ProjectVG.Application.Services.Chat;
+using ProjectVG.Application.Services.Chat.CostTracking;
 using ProjectVG.Application.Services.Chat.Preprocessors;
 using ProjectVG.Application.Services.Chat.Processors;
 using ProjectVG.Application.Services.Chat.Validators;
+using ProjectVG.Application.Services.Chat.Handlers;
 using ProjectVG.Application.Services.WebSocket;
 using ProjectVG.Application.Services.Conversation;
 using ProjectVG.Application.Services.Session;
@@ -27,11 +29,19 @@ public static IServiceCollection AddApplicationServices(this IServiceCollection
             services.AddScoped<UserInputAnalysisProcessor>();
             services.AddScoped<UserInputActionProcessor>();
             services.AddScoped<MemoryContextPreprocessor>();
+            services.AddScoped<ChatFailureHandler>();
 
             services.AddScoped<IWebSocketManager, WebSocketManager>();
             services.AddScoped<IChatService, ChatService>();
             services.AddScoped<IConversationService, ConversationService>();
             services.AddSingleton<IConnectionRegistry, ConnectionRegistry>();
+            
+            services.AddScoped<IChatMetricsService, ChatMetricsService>();
+
+            // 비용 추적 데코레이터 등록
+            services.AddCostTrackingDecorator<ChatLLMProcessor>("LLM_Processing");
+            services.AddCostTrackingDecorator<ChatTTSProcessor>("TTS_Processing");
+            services.AddCostTrackingDecorator<UserInputAnalysisProcessor>("User_Input_Analysis");
 
             return services;
         }
diff --git a/ProjectVG.Application/Models/Chat/ChatMessageSegment.cs b/ProjectVG.Application/Models/Chat/ChatMessageSegment.cs
index 410240d..d520e64 100644
--- a/ProjectVG.Application/Models/Chat/ChatMessageSegment.cs
+++ b/ProjectVG.Application/Models/Chat/ChatMessageSegment.cs
@@ -13,51 +13,6 @@ public class ChatMessageSegment
         public bool HasAudio => AudioData != null && AudioData.Length > 0;
         public bool IsEmpty => !HasText && !HasAudio;
         
-        public override string ToString()
-        {
-            var parts = new List<string>();
-            
-            parts.Add($"Order: {Order}");
-            
-            if (HasText)
-            {
-                parts.Add($"Text: \"{Text}\"");
-            }
-            
-            if (HasAudio)
-            {
-                parts.Add($"Audio: {AudioData!.Length} bytes, {AudioContentType}, {AudioLength:F2}s");
-            }
-            
-            if (!string.IsNullOrEmpty(Emotion))
-            {
-                parts.Add($"Emotion: {Emotion}");
-            }
-            
-            return $"Segment({string.Join(", ", parts)})";
-        }
-        
-        public string ToShortString()
-        {
-            var parts = new List<string>();
-            
-            if (HasText)
-            {
-                parts.Add($"\"{Text}\"");
-            }
-            
-            if (HasAudio)
-            {
-                parts.Add($"[Audio: {AudioLength:F1}s]");
-            }
-            
-            return string.Join(" ", parts);
-        }
-        
-        public string ToDebugString()
-        {
-            return $"Segment[Order={Order}, Text={HasText}, Audio={HasAudio}, Emotion={Emotion ?? "none"}, AudioSize={AudioData?.Length ?? 0} bytes, AudioLength={AudioLength:F2}s]";
-        }
         
         public static ChatMessageSegment CreateTextOnly(string text, int order = 0)
         {
@@ -67,29 +22,14 @@ public static ChatMessageSegment CreateTextOnly(string text, int order = 0)
                 Order = order
             };
         }
-        
-        public static ChatMessageSegment CreateAudioOnly(byte[] audioData, string contentType, float? audioLength, int order = 0)
+
+        public void SetAudioData(byte[]? audioData, string? audioContentType, float? audioLength)
         {
-            return new ChatMessageSegment
-            {
-                AudioData = audioData,
-                AudioContentType = contentType,
-                AudioLength = audioLength,
-                Order = order
-            };
+            AudioData = audioData;
+            AudioContentType = audioContentType;
+            AudioLength = audioLength;
         }
         
-        public static ChatMessageSegment CreateIntegrated(string text, byte[] audioData, string contentType, float? audioLength, string? emotion = null, int order = 0)
-        {
-            return new ChatMessageSegment
-            {
-                Text = text,
-                AudioData = audioData,
-                AudioContentType = contentType,
-                AudioLength = audioLength,
-                Emotion = emotion,
-                Order = order
-            };
-        }
+
     }
 }
diff --git a/ProjectVG.Application/Models/Chat/ChatMetrics.cs b/ProjectVG.Application/Models/Chat/ChatMetrics.cs
new file mode 100644
index 0000000..b353ea5
--- /dev/null
+++ b/ProjectVG.Application/Models/Chat/ChatMetrics.cs
@@ -0,0 +1,25 @@
+namespace ProjectVG.Application.Models.Chat
+{
+    public class ChatMetrics
+    {
+        public string SessionId { get; set; } = string.Empty;
+        public string UserId { get; set; } = string.Empty;
+        public string CharacterId { get; set; } = string.Empty;
+        public DateTime StartTime { get; set; }
+        public DateTime EndTime { get; set; }
+        public List<ProcessMetrics> ProcessMetrics { get; set; } = new();
+        public decimal TotalCost { get; set; }
+        public TimeSpan TotalDuration { get; set; }
+    }
+
+    public class ProcessMetrics
+    {
+        public string ProcessName { get; set; } = string.Empty;
+        public DateTime StartTime { get; set; }
+        public DateTime EndTime { get; set; }
+        public TimeSpan Duration { get; set; }
+        public decimal Cost { get; set; }
+        public string? ErrorMessage { get; set; }
+        public Dictionary<string, object>? AdditionalData { get; set; }
+    }
+}
diff --git a/ProjectVG.Application/Models/Chat/ChatOutputFormatResult.cs b/ProjectVG.Application/Models/Chat/ChatOutputFormatResult.cs
deleted file mode 100644
index 3e6da41..0000000
--- a/ProjectVG.Application/Models/Chat/ChatOutputFormatResult.cs
+++ /dev/null
@@ -1,9 +0,0 @@
-namespace ProjectVG.Application.Models.Chat
-{
-    public class ChatOutputFormatResult
-    {
-        public string Response { get; set; } = string.Empty;
-        public List<string> Emotion { get; set; } = new List<string>();
-        public List<string> Text { get; set; } = new List<string>();
-    }
-}
diff --git a/ProjectVG.Application/Models/Chat/ChatPreprocessContext.cs b/ProjectVG.Application/Models/Chat/ChatPreprocessContext.cs
deleted file mode 100644
index 3458c62..0000000
--- a/ProjectVG.Application/Models/Chat/ChatPreprocessContext.cs
+++ /dev/null
@@ -1,86 +0,0 @@
-using Microsoft.Extensions.Logging;
-using ProjectVG.Application.Models.Character;
-using ProjectVG.Domain.Entities.ConversationHistorys;
-using ProjectVG.Domain.Enums;
-
-namespace ProjectVG.Application.Models.Chat
-{
-    public class ChatPreprocessContext
-    {
-        public string SessionId { get; set; } = string.Empty;
-        public Guid UserId { get; set; }
-        public Guid CharacterId { get; set; }
-        public string UserMessage { get; set; } = string.Empty;
-        
-        public string? Action { get; set; }
-        public List<string> MemoryContext { get; set; } = new();
-        public IEnumerable<ConversationHistory> ConversationHistory { get; set; } = new List<ConversationHistory>();
-
-        public string MemoryStore { get; set; } = string.Empty;
-        public string VoiceName { get; set; } = string.Empty;
-        public CharacterDto? Character { get; set; }
-
-        public ChatPreprocessContext(
-            ProcessChatCommand command,
-            List<string> memoryContext,
-            IEnumerable<ConversationHistory> conversationHistory)
-        {
-            SessionId = command.SessionId;
-            UserId = command.UserId;
-            CharacterId = command.CharacterId;
-            UserMessage = command.Message;
-            MemoryStore = command.UserId.ToString();
-            Action = command.Action;
-            MemoryContext = memoryContext ?? new List<string>();
-            ConversationHistory = conversationHistory ?? new List<ConversationHistory>();
-            
-            Character = command.Character!;
-            VoiceName = command.Character!.VoiceId;
-        }
-
-        public List<string> ParseConversationHistory()
-        {
-            return ConversationHistory?.Select(c => $"{c.Role}: {c.Content}").ToList() ?? new List<string>();
-        }
-
-        public List<string> ParseConversationHistory(int takeCount)
-        {
-            return ConversationHistory?.Take(takeCount).Select(c => $"{c.Role}: {c.Content}").ToList() ?? new List<string>();
-        }
-
-        public override string ToString()
-        {
-            return $"ChatPreprocessContext(SessionId={SessionId}, UserId={UserId}, CharacterId={CharacterId}, UserMessage='{UserMessage}', MemoryContext.Count={MemoryContext.Count}, ConversationHistory.Count={ConversationHistory.Count()})";
-        }
-
-        public string GetDetailedInfo()
-        {
-            var info = new System.Text.StringBuilder();
-            info.AppendLine("=== ChatPreprocessContext ===");
-            info.AppendLine($"SessionId: {SessionId}");
-            info.AppendLine($"UserId: {UserId}");
-            info.AppendLine($"CharacterId: {CharacterId}");
-            info.AppendLine($"Action: {Action ?? "N/A"}");
-            info.AppendLine($"VoiceName: {VoiceName}");
-            info.AppendLine($"MemoryStore: {MemoryStore}");
-            info.AppendLine($"UserMessage: {UserMessage}");
-            info.AppendLine($"Character: {(Character != null ? Character.Name : "Not Loaded")}");
-            
-            info.AppendLine($"MemoryContext ({MemoryContext.Count} items):");
-            for (int i = 0; i < MemoryContext.Count; i++)
-            {
-                info.AppendLine($"  [{i}]: {MemoryContext[i]}");
-            }
-            
-            info.AppendLine($"ConversationHistory ({ConversationHistory.Count()} items):");
-            var parsedHistory = ParseConversationHistory();
-            for (int i = 0; i < parsedHistory.Count; i++)
-            {
-                info.AppendLine($"  [{i}]: {parsedHistory[i]}");
-            }
-            info.AppendLine("=== End ChatPreprocessContext ===");
-            
-            return info.ToString();
-        }
-    }
-}
diff --git a/ProjectVG.Application/Models/Chat/ChatPreprocessResult.cs b/ProjectVG.Application/Models/Chat/ChatPreprocessResult.cs
deleted file mode 100644
index 592bcb3..0000000
--- a/ProjectVG.Application/Models/Chat/ChatPreprocessResult.cs
+++ /dev/null
@@ -1,27 +0,0 @@
-namespace ProjectVG.Application.Models.Chat
-{
-    public class ChatPreprocessResult
-    {
-        public bool IsValid { get; private set; }
-        public ChatRequestResponse? RequestResponse { get; private set; }
-        public ChatPreprocessContext? Context { get; private set; }
-
-        public static ChatPreprocessResult Success(ChatPreprocessContext context)
-        {
-            return new ChatPreprocessResult
-            {
-                IsValid = true,
-                Context = context
-            };
-        }
-
-        public static ChatPreprocessResult Failure(ChatRequestResponse requestResponse)
-        {
-            return new ChatPreprocessResult
-            {
-                IsValid = false,
-                RequestResponse = requestResponse
-            };
-        }
-    }
-}
diff --git a/ProjectVG.Application/Models/Chat/ChatProcessContext.cs b/ProjectVG.Application/Models/Chat/ChatProcessContext.cs
new file mode 100644
index 0000000..d0900ec
--- /dev/null
+++ b/ProjectVG.Application/Models/Chat/ChatProcessContext.cs
@@ -0,0 +1,77 @@
+using ProjectVG.Application.Models.Character;
+using ProjectVG.Domain.Entities.ConversationHistorys;
+
+namespace ProjectVG.Application.Models.Chat
+{
+    public class ChatProcessContext
+    {
+        public string SessionId { get; private set; } = string.Empty;
+        public Guid UserId { get; private set; }
+        public Guid CharacterId { get; private set; }
+        public string UserMessage { get; private set; } = string.Empty;
+        public string MemoryStore { get; private set; } = string.Empty;
+        public bool UseTTS { get; private set; } = true;
+        
+        public CharacterDto? Character { get; private set; }
+        public IEnumerable<string>? MemoryContext { get; private set; }
+        public IEnumerable<ConversationHistory>? ConversationHistory { get; private set; }
+        
+        public string Response { get; private set; } = string.Empty;
+        public double Cost { get; private set; }
+        public List<ChatMessageSegment> Segments { get; private set; } = new List<ChatMessageSegment>();
+        
+        public string FullText => string.Join(" ", Segments.Where(s => s.HasText).Select(s => s.Text));
+        public bool HasAudio => Segments.Any(s => s.HasAudio);
+        public bool HasText => Segments.Any(s => s.HasText);
+
+
+        public ChatProcessContext(ProcessChatCommand command)
+        {
+            SessionId = command.SessionId;
+            UserId = command.UserId;
+            CharacterId = command.CharacterId;
+            UserMessage = command.Message;
+            MemoryStore = command.UserId.ToString();
+            UseTTS = command.UseTTS;
+        }
+
+        public ChatProcessContext(
+            ProcessChatCommand command,
+            CharacterDto character,
+            IEnumerable<ConversationHistory> conversationHistory,
+            IEnumerable<string> memoryContext)
+        {
+            SessionId = command.SessionId;
+            UserId = command.UserId;
+            CharacterId = command.CharacterId;
+            UserMessage = command.Message;
+            MemoryStore = command.UserId.ToString();
+            UseTTS = command.UseTTS;
+            
+            Character = character;
+            ConversationHistory = conversationHistory;
+            MemoryContext = memoryContext;
+        }
+
+        public void SetResponse(string response, List<ChatMessageSegment> segments, double cost)
+        {
+            Response = response;
+            Segments = segments;
+            Cost = cost;
+        }
+
+        public void AddCost(double additionalCost)
+        {
+            Cost += additionalCost;
+        }
+
+        public IEnumerable<string> ParseConversationHistory(int count = 5)
+        {
+            if (ConversationHistory == null) return Enumerable.Empty<string>();
+
+            return ConversationHistory
+                .Take(count)
+                .Select(h => $"{h.Role}: {h.Content}");
+        }
+    }
+}
diff --git a/ProjectVG.Application/Models/Chat/ChatProcessResult.cs b/ProjectVG.Application/Models/Chat/ChatProcessResult.cs
deleted file mode 100644
index 3089f51..0000000
--- a/ProjectVG.Application/Models/Chat/ChatProcessResult.cs
+++ /dev/null
@@ -1,17 +0,0 @@
-namespace ProjectVG.Application.Models.Chat
-{
-    public class ChatProcessResult
-    {
-        public string Response { get; set; } = string.Empty;
-        public int TokensUsed { get; set; }
-        public double Cost { get; set; }
-        
-        public List<ChatMessageSegment> Segments { get; set; } = new List<ChatMessageSegment>();
-        
-        public string FullText => string.Join(" ", Segments.Where(s => s.HasText).Select(s => s.Text));
-        
-        public bool HasAudio => Segments.Any(s => s.HasAudio);
-        
-        public bool HasText => Segments.Any(s => s.HasText);
-    }
-}
diff --git a/ProjectVG.Application/Models/Chat/ProcessChatCommand.cs b/ProjectVG.Application/Models/Chat/ProcessChatCommand.cs
index bb322c6..37c3e75 100644
--- a/ProjectVG.Application/Models/Chat/ProcessChatCommand.cs
+++ b/ProjectVG.Application/Models/Chat/ProcessChatCommand.cs
@@ -18,6 +18,7 @@ public string RequestId
         public DateTime RequestedAt { get; set; }
         public string? Action { get; set; }
         public string? Instruction { get; set; }
+        public bool UseTTS { get; set; } = true;
 
         public CharacterDto? Character { get; private set; }
 
diff --git a/ProjectVG.Application/Models/Chat/UserInputAnalysis.cs b/ProjectVG.Application/Models/Chat/UserInputAnalysis.cs
index 57e98fb..60fe74b 100644
--- a/ProjectVG.Application/Models/Chat/UserInputAnalysis.cs
+++ b/ProjectVG.Application/Models/Chat/UserInputAnalysis.cs
@@ -9,6 +9,7 @@ public class UserInputAnalysis
         public List<string> Keywords { get; set; } = new List<string>();
         public string? EnhancedQuery { get; set; }
         public DateTime? ContextTime { get; set; }
+        public double Cost { get; set; }
 
         private UserInputAnalysis()
         {
@@ -20,7 +21,8 @@ public static UserInputAnalysis CreateValid(
             UserInputAction action,
             List<string> keywords,
             string? enhancedQuery = null,
-            DateTime? contextTime = null)
+            DateTime? contextTime = null,
+            double cost = 0)
         {
             return new UserInputAnalysis
             {
@@ -29,7 +31,8 @@ public static UserInputAnalysis CreateValid(
                 Action = action,
                 Keywords = keywords,
                 EnhancedQuery = enhancedQuery,
-                ContextTime = contextTime
+                ContextTime = contextTime,
+                Cost = cost
             };
         }
 
diff --git a/ProjectVG.Application/Services/Chat/ChatService.cs b/ProjectVG.Application/Services/Chat/ChatService.cs
index 9947bc4..a9def06 100644
--- a/ProjectVG.Application/Services/Chat/ChatService.cs
+++ b/ProjectVG.Application/Services/Chat/ChatService.cs
@@ -1,6 +1,8 @@
 using ProjectVG.Application.Services.Chat.Preprocessors;
 using ProjectVG.Application.Services.Chat.Processors;
 using ProjectVG.Application.Services.Chat.Validators;
+using ProjectVG.Application.Services.Chat.CostTracking;
+using ProjectVG.Application.Services.Chat.Handlers;
 using ProjectVG.Application.Services.Conversation;
 using ProjectVG.Application.Services.Character;
 using Microsoft.Extensions.DependencyInjection;
@@ -18,12 +20,14 @@ public class ChatService : IChatService
 
         private readonly ChatRequestValidator _validator;
         private readonly MemoryContextPreprocessor _memoryPreprocessor;
-        private readonly UserInputAnalysisProcessor _inputProcessor;
+        private readonly ICostTrackingDecorator<UserInputAnalysisProcessor> _inputProcessor;
         private readonly UserInputActionProcessor _actionProcessor;
 
-        private readonly ChatLLMProcessor _llmProcessor;
-        private readonly ChatTTSProcessor _ttsProcessor;
+        private readonly ICostTrackingDecorator<ChatLLMProcessor> _llmProcessor;
+        private readonly ICostTrackingDecorator<ChatTTSProcessor> _ttsProcessor;
         private readonly ChatResultProcessor _resultProcessor;
+        private readonly IChatMetricsService _metricsService;
+        private readonly ChatFailureHandler _failureHandler;
 
         public ChatService(
             IServiceScopeFactory scopeFactory,
@@ -32,11 +36,13 @@ public ChatService(
             ICharacterService characterService,
             ChatRequestValidator validator,
             MemoryContextPreprocessor memoryPreprocessor,
-            UserInputAnalysisProcessor inputProcessor,
+            ICostTrackingDecorator<UserInputAnalysisProcessor> inputProcessor,
             UserInputActionProcessor actionProcessor,
-            ChatLLMProcessor llmProcessor,
-            ChatTTSProcessor ttsProcessor,
-            ChatResultProcessor resultProcessor
+            ICostTrackingDecorator<ChatLLMProcessor> llmProcessor,
+            ICostTrackingDecorator<ChatTTSProcessor> ttsProcessor,
+            ChatResultProcessor resultProcessor,
+            IChatMetricsService metricsService,
+            ChatFailureHandler failureHandler
         ) {
             _scopeFactory = scopeFactory;
             _logger = logger;
@@ -50,16 +56,19 @@ ChatResultProcessor resultProcessor
             _llmProcessor = llmProcessor;
             _ttsProcessor = ttsProcessor;
             _resultProcessor = resultProcessor;
+            _metricsService = metricsService;
+            _failureHandler = failureHandler;
         }
 
         public async Task<ChatRequestResponse> EnqueueChatRequestAsync(ProcessChatCommand command)
         {
+            _metricsService.StartChatMetrics(command.SessionId, command.UserId.ToString(), command.CharacterId.ToString());
+            
             await _validator.ValidateAsync(command);
 
             var preprocessContext = await PrepareChatRequestAsync(command);
 
             _ = Task.Run(async () => {
-                using var processScope = _scopeFactory.CreateScope();
                 await ProcessChatRequestInternalAsync(preprocessContext);
             });
 
@@ -70,11 +79,9 @@ public async Task<ChatRequestResponse> EnqueueChatRequestAsync(ProcessChatComman
         /// <summary>
         /// 채팅 요청 준비
         /// </summary>
-        private async Task<ChatPreprocessContext> PrepareChatRequestAsync(ProcessChatCommand command)
+        private async Task<ChatProcessContext> PrepareChatRequestAsync(ProcessChatCommand command)
         {
             var characterDto = await _characterService.GetCharacterByIdAsync(command.CharacterId);
-            command.SetCharacter(characterDto!);
-            
             var conversationHistory = await _conversationService.GetConversationHistoryAsync(command.UserId, command.CharacterId, 10);
 
             var inputAnalysis = await _inputProcessor.ProcessAsync(command.Message, conversationHistory);
@@ -82,32 +89,30 @@ private async Task<ChatPreprocessContext> PrepareChatRequestAsync(ProcessChatCom
             
             var memoryContext = await _memoryPreprocessor.CollectMemoryContextAsync(command.UserId.ToString(), command.Message, inputAnalysis);
 
-            return new ChatPreprocessContext(
-                command,
-                memoryContext,
-                conversationHistory
-            );
+            return new ChatProcessContext(command, characterDto!, conversationHistory, memoryContext);
         }
 
         /// <summary>
         /// 채팅 요청 처리
         /// </summary>
-        private async Task ProcessChatRequestInternalAsync(ChatPreprocessContext context)
+        private async Task ProcessChatRequestInternalAsync(ChatProcessContext context)
         {
             try {
-                _logger.LogInformation("채팅 요청 처리 시작: {SessionId}", context.SessionId);
-
                 // 작업 처리 단계: LLM -> TTS -> 결과 전송 + 저장
-                var llmResult = await _llmProcessor.ProcessAsync(context);
-                await _ttsProcessor.ProcessAsync(context, llmResult);
-                await _resultProcessor.SendResultsAsync(context, llmResult);
-                await _resultProcessor.PersistResultsAsync(context, llmResult);
-
-                _logger.LogInformation("채팅 요청 처리 완료: {SessionId}, 토큰: {TokensUsed}",
-                    context.SessionId, llmResult.TokensUsed);
+                await _llmProcessor.ProcessAsync(context);
+                await _ttsProcessor.ProcessAsync(context);
+                
+                using var scope = _scopeFactory.CreateScope();
+                var resultProcessor = scope.ServiceProvider.GetRequiredService<ChatResultProcessor>();
+                await resultProcessor.SendResultsAsync(context);
+                await resultProcessor.PersistResultsAsync(context);
             }
             catch (Exception ex) {
-                _logger.LogError(ex, "채팅 요청 처리 중 오류 발생: {SessionId}", context.SessionId);
+                await _failureHandler.HandleFailureAsync(context, ex);
+            }
+            finally {
+                _metricsService.EndChatMetrics();
+                _metricsService.LogChatMetrics();
             }
         }
     }
diff --git a/ProjectVG.Application/Services/Chat/CostTracking/ChatMetricsService.cs b/ProjectVG.Application/Services/Chat/CostTracking/ChatMetricsService.cs
new file mode 100644
index 0000000..0dcc4f5
--- /dev/null
+++ b/ProjectVG.Application/Services/Chat/CostTracking/ChatMetricsService.cs
@@ -0,0 +1,94 @@
+using ProjectVG.Application.Models.Chat;
+using ProjectVG.Application.Services.Chat.CostTracking;
+
+namespace ProjectVG.Application.Services.Chat.CostTracking
+{
+    public class ChatMetricsService : IChatMetricsService
+    {
+        private readonly ILogger<ChatMetricsService> _logger;
+        private readonly AsyncLocal<ChatMetrics?> _currentMetrics = new();
+
+        public ChatMetricsService(ILogger<ChatMetricsService> logger)
+        {
+            _logger = logger;
+        }
+
+        public void StartChatMetrics(string sessionId, string userId, string characterId)
+        {
+            _currentMetrics.Value = new ChatMetrics
+            {
+                SessionId = sessionId,
+                UserId = userId,
+                CharacterId = characterId,
+                StartTime = DateTime.UtcNow
+            };
+            Console.WriteLine($"[METRICS] 채팅 메트릭 시작: {sessionId}");
+        }
+
+        public void StartProcessMetrics(string processName)
+        {
+            if (_currentMetrics.Value == null) return;
+
+            var processMetrics = new ProcessMetrics
+            {
+                ProcessName = processName,
+                StartTime = DateTime.UtcNow
+            };
+
+            _currentMetrics.Value.ProcessMetrics.Add(processMetrics);
+            Console.WriteLine($"[METRICS] 프로세스 시작: {processName}");
+        }
+
+        public void EndProcessMetrics(string processName, decimal cost = 0, string? errorMessage = null, Dictionary<string, object>? additionalData = null)
+        {
+            if (_currentMetrics.Value == null) return;
+
+            var processMetrics = _currentMetrics.Value.ProcessMetrics
+                .FirstOrDefault(p => p.ProcessName == processName && p.EndTime == default);
+
+            if (processMetrics != null)
+            {
+                processMetrics.EndTime = DateTime.UtcNow;
+                processMetrics.Duration = processMetrics.EndTime - processMetrics.StartTime;
+                processMetrics.Cost = cost;
+                processMetrics.ErrorMessage = errorMessage;
+                processMetrics.AdditionalData = additionalData;
+            }
+        }
+
+        public void EndChatMetrics()
+        {
+            if (_currentMetrics.Value == null) return;
+
+            _currentMetrics.Value.EndTime = DateTime.UtcNow;
+            _currentMetrics.Value.TotalDuration = _currentMetrics.Value.EndTime - _currentMetrics.Value.StartTime;
+            _currentMetrics.Value.TotalCost = _currentMetrics.Value.ProcessMetrics.Sum(p => p.Cost);
+        }
+
+        public ChatMetrics? GetCurrentChatMetrics()
+        {
+            return _currentMetrics.Value;
+        }
+
+        public void LogChatMetrics()
+        {
+            var metrics = _currentMetrics.Value;
+            if (metrics == null) return;
+
+            Console.WriteLine($"[METRICS] 채팅 메트릭 로그 시작: {metrics.SessionId}");
+
+            var totalCostInDollars = (double)metrics.TotalCost / 100_000.0;
+            _logger.LogInformation(
+                "채팅 메트릭 - SessionId: {SessionId}, 총 비용: ${TotalCost:F6}, 총 시간: {TotalDuration}",
+                metrics.SessionId, totalCostInDollars, metrics.TotalDuration);
+
+            foreach (var process in metrics.ProcessMetrics)
+            {
+                var processCostInDollars = (double)process.Cost / 100_000.0;
+                _logger.LogInformation(
+                    "  - {ProcessName}: {Duration}ms, 비용: ${Cost:F6}",
+                    process.ProcessName, process.Duration.TotalMilliseconds, processCostInDollars);
+            }
+        }
+    }
+}
diff --git a/ProjectVG.Application/Services/Chat/CostTracking/CostTrackingDecorator.cs b/ProjectVG.Application/Services/Chat/CostTracking/CostTrackingDecorator.cs
new file mode 100644
index 0000000..b2e7779
--- /dev/null
+++ b/ProjectVG.Application/Services/Chat/CostTracking/CostTrackingDecorator.cs
@@ -0,0 +1,114 @@
+using ProjectVG.Application.Models.Chat;
+using ProjectVG.Application.Services.Chat.CostTracking;
+using ProjectVG.Domain.Entities.ConversationHistorys;
+
+namespace ProjectVG.Application.Services.Chat.CostTracking
+{
+    public class CostTrackingDecorator<T> : ICostTrackingDecorator<T> where T : class
+    {
+        private readonly T _service;
+        private readonly IChatMetricsService _metricsService;
+        private readonly string _processName;
+
+        public CostTrackingDecorator(T service, IChatMetricsService metricsService, string processName)
+        {
+            _service = service;
+            _metricsService = metricsService;
+            _processName = processName;
+        }
+
+        public T Service => _service;
+
+        private decimal ExtractCost(object? result)
+        {
+            if (result == null) return 0;
+
+            var resultType = result.GetType();
+            
+            // Cost 속성이 있는 경우
+            var costProperty = resultType.GetProperty("Cost");
+            if (costProperty != null)
+            {
+                var costValue = costProperty.GetValue(result);
+                if (costValue != null)
+                {
+                    // double, decimal, int 등 다양한 타입 지원
+                    return Convert.ToDecimal(costValue);
+                }
+            }
+            
+            return 0;
+        }
+
+        public async Task ProcessAsync(ChatProcessContext context)
+        {
+            _metricsService.StartProcessMetrics(_processName);
+            
+            try
+            {
+                // 리플렉션으로 ProcessAsync 메서드 호출
+                var method = typeof(T).GetMethod("ProcessAsync", new[] { typeof(ChatProcessContext) });
+                
+                if (method == null)
+                    throw new InvalidOperationException($"ProcessAsync 메서드를 찾을 수 없습니다: {typeof(T).Name}");
+
+                var invokeResult = method.Invoke(_service, new object[] { context });
+                if (invokeResult == null)
+                    throw new InvalidOperationException($"ProcessAsync 메서드 호출 결과가 null입니다: {typeof(T).Name}");
+                
+                if (invokeResult is not Task taskResult)
+                    throw new InvalidOperationException($"ProcessAsync 메서드 반환 타입이 올바르지 않습니다: {typeof(T).Name}");
+                
+                await taskResult;
+                
+                // Cost 값만 직접 추출
+                var cost = ExtractCost(context);
+                Console.WriteLine($"[COST_TRACKING] {_processName} - 추출된 비용: {cost:F0} Cost");
+                Console.WriteLine($"[COST_TRACKING] {_processName} - 컨텍스트 타입: {context?.GetType().Name}, Cost 속성 값: {context?.GetType().GetProperty("Cost")?.GetValue(context)}");
+                _metricsService.EndProcessMetrics(_processName, cost);
+            }
+            catch (Exception ex)
+            {
+                _metricsService.EndProcessMetrics(_processName, 0, ex.Message);
+                throw;
+            }
+        }
+
+
+
+        public async Task<UserInputAnalysis> ProcessAsync(string userInput, IEnumerable<ConversationHistory> conversationHistory)
+        {
+            _metricsService.StartProcessMetrics(_processName);
+            
+            try
+            {
+                // 리플렉션으로 ProcessAsync 메서드 호출
+                var method = typeof(T).GetMethod("ProcessAsync", new[] { typeof(string), typeof(IEnumerable<ConversationHistory>) });
+                
+                if (method == null)
+                    throw new InvalidOperationException($"ProcessAsync 메서드를 찾을 수 없습니다: {typeof(T).Name}");
+
+                var invokeResult = method.Invoke(_service, new object[] { userInput, conversationHistory });
+                if (invokeResult == null)
+                    throw new InvalidOperationException($"ProcessAsync 메서드 호출 결과가 null입니다: {typeof(T).Name}");
+                
+                if (invokeResult is not Task<UserInputAnalysis> taskResult)
+                    throw new InvalidOperationException($"ProcessAsync 메서드 반환 타입이 올바르지 않습니다: {typeof(T).Name}");
+                
+                var result = await taskResult!;
+                
+                // Cost 값만 직접 추출
+                var cost = ExtractCost(result);
+                Console.WriteLine($"[COST_TRACKING] {_processName} - 추출된 비용: {cost:F0} Cost");
+                Console.WriteLine($"[COST_TRACKING] {_processName} - 원본 결과 타입: {result?.GetType().Name}, Cost 속성 값: {result?.GetType().GetProperty("Cost")?.GetValue(result)}");
+                _metricsService.EndProcessMetrics(_processName, cost);
+                return result;
+            }
+            catch (Exception ex)
+            {
+                _metricsService.EndProcessMetrics(_processName, 0, ex.Message);
+                throw;
+            }
+        }
+    }
+}
diff --git a/ProjectVG.Application/Services/Chat/CostTracking/CostTrackingDecoratorFactory.cs b/ProjectVG.Application/Services/Chat/CostTracking/CostTrackingDecoratorFactory.cs
new file mode 100644
index 0000000..ed152b6
--- /dev/null
+++ b/ProjectVG.Application/Services/Chat/CostTracking/CostTrackingDecoratorFactory.cs
@@ -0,0 +1,32 @@
+using Microsoft.Extensions.DependencyInjection;
+using ProjectVG.Application.Models.Chat;
+using ProjectVG.Application.Services.Chat.CostTracking;
+
+namespace ProjectVG.Application.Services.Chat.CostTracking
+{
+    public static class CostTrackingDecoratorFactory
+    {
+        public static IServiceCollection AddCostTrackingDecorator<T>(
+            this IServiceCollection services,
+            string processName,
+            ServiceLifetime lifetime = ServiceLifetime.Scoped)
+            where T : class
+        {
+            // 원본 서비스 등록
+            services.Add(new ServiceDescriptor(typeof(T), typeof(T), lifetime));
+
+            // 비용 추적 데코레이터 등록
+            services.Add(new ServiceDescriptor(
+                typeof(ICostTrackingDecorator<T>),
+                provider =>
+                {
+                    var service = provider.GetRequiredService<T>();
+                    var metricsService = provider.GetRequiredService<IChatMetricsService>();
+                    return new CostTrackingDecorator<T>(service, metricsService, processName);
+                },
+                lifetime));
+
+            return services;
+        }
+    }
+}
diff --git a/ProjectVG.Application/Services/Chat/CostTracking/IChatMetricsService.cs b/ProjectVG.Application/Services/Chat/CostTracking/IChatMetricsService.cs
new file mode 100644
index 0000000..67c9e8d
--- /dev/null
+++ b/ProjectVG.Application/Services/Chat/CostTracking/IChatMetricsService.cs
@@ -0,0 +1,14 @@
+using ProjectVG.Application.Models.Chat;
+
+namespace ProjectVG.Application.Services.Chat.CostTracking
+{
+    public interface IChatMetricsService
+    {
+        void StartChatMetrics(string sessionId, string userId, string characterId);
+        void StartProcessMetrics(string processName);
+        void EndProcessMetrics(string processName, decimal cost = 0, string? errorMessage = null, Dictionary<string, object>? additionalData = null);
+        void EndChatMetrics();
+        ChatMetrics? GetCurrentChatMetrics();
+        void LogChatMetrics();
+    }
+}
diff --git a/ProjectVG.Application/Services/Chat/CostTracking/ICostTrackingDecorator.cs b/ProjectVG.Application/Services/Chat/CostTracking/ICostTrackingDecorator.cs
new file mode 100644
index 0000000..61b1e66
--- /dev/null
+++ b/ProjectVG.Application/Services/Chat/CostTracking/ICostTrackingDecorator.cs
@@ -0,0 +1,12 @@
+using ProjectVG.Application.Models.Chat;
+using ProjectVG.Domain.Entities.ConversationHistorys;
+
+namespace ProjectVG.Application.Services.Chat.CostTracking
+{
+    public interface ICostTrackingDecorator<T> where T : class
+    {
+        T Service { get; }
+        Task ProcessAsync(ChatProcessContext context);
+        Task<UserInputAnalysis> ProcessAsync(string userInput, IEnumerable<ConversationHistory> conversationHistory);
+    }
+}
diff --git a/ProjectVG.Application/Services/Chat/Factories/ChatLLMFormat.cs b/ProjectVG.Application/Services/Chat/Factories/ChatLLMFormat.cs
index 207b267..1a390d7 100644
--- a/ProjectVG.Application/Services/Chat/Factories/ChatLLMFormat.cs
+++ b/ProjectVG.Application/Services/Chat/Factories/ChatLLMFormat.cs
@@ -5,13 +5,13 @@
 
 namespace ProjectVG.Application.Services.Chat.Factories
 {
-    public class ChatLLMFormat : ILLMFormat<ChatPreprocessContext, ChatOutputFormatResult>
+    public class ChatLLMFormat : ILLMFormat<ChatProcessContext, List<ChatMessageSegment>>
     {
         public ChatLLMFormat()
         {
         }
 
-        public string GetSystemMessage(ChatPreprocessContext input)
+        public string GetSystemMessage(ChatProcessContext input)
         {
             var character = input.Character ?? throw new InvalidOperationException("캐릭터 정보가 로드되지 않았습니다.");
             
@@ -25,11 +25,10 @@ public string GetSystemMessage(ChatPreprocessContext input)
             return sb.ToString();
         }
 
-        public string GetInstructions(ChatPreprocessContext input)
+        public string GetInstructions(ChatProcessContext input)
         {
             var sb = new StringBuilder();
             
-            // 메모리 컨텍스트 추가
             if (input.MemoryContext?.Any() == true)
             {
                 sb.AppendLine("관련 기억:");
@@ -40,7 +39,6 @@ public string GetInstructions(ChatPreprocessContext input)
                 sb.AppendLine();
             }
             
-            // 대화 기록 추가
             var conversationHistory = input.ParseConversationHistory(5);
             if (conversationHistory.Any())
             {
@@ -52,7 +50,6 @@ public string GetInstructions(ChatPreprocessContext input)
                 sb.AppendLine();
             }
             
-            // 출력 포맷 지침 추가
             sb.AppendLine(GetFormatInstructions());
             
             return sb.ToString();
@@ -62,18 +59,14 @@ public string GetInstructions(ChatPreprocessContext input)
         public float Temperature => 0.7f;
         public int MaxTokens => 1000;
 
-        public ChatOutputFormatResult Parse(string llmResponse, ChatPreprocessContext input)
+        public List<ChatMessageSegment> Parse(string llmResponse, ChatProcessContext input)
         {
-            return ParseChatResponse(llmResponse, input.VoiceName);
+            return ParseChatResponseToSegments(llmResponse, input.Character?.VoiceId);
         }
 
-        public double CalculateCost(int tokensUsed)
+        public double CalculateCost(int promptTokens, int completionTokens)
         {
-            var inputCost = LLMModelInfo.GetInputCost(Model);
-            var outputCost = LLMModelInfo.GetOutputCost(Model);
-            
-            // 토큰 수를 백만 단위로 변환하여 비용 계산
-            return (tokensUsed / 1_000_000.0) * (inputCost + outputCost);
+            return LLMModelInfo.CalculateCost(Model, promptTokens, completionTokens);
         }
 
         private string GetFormatInstructions()
@@ -89,54 +82,63 @@ [neutral] 내가 그런다고 좋아할 것 같아? [shy] 하지만 츄 해준
 ";
         }
 
-        private ChatOutputFormatResult ParseChatResponse(string llmText, string? voiceName = null)
+        private List<ChatMessageSegment> ParseChatResponseToSegments(string llmText, string? voiceId = null)
         {
             if (string.IsNullOrWhiteSpace(llmText))
-                return new ChatOutputFormatResult();
+                return new List<ChatMessageSegment>();
 
             string response = llmText.Trim();
-            var emotions = new List<string>();
-            var texts = new List<string>();
+            var segments = new List<ChatMessageSegment>();
+            var seenTexts = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
 
-            // [감정] 답변 패턴 추출
             var matches = Regex.Matches(response, @"\[(.*?)\]\s*([^\[]+)");
-            
-            // 보이스별 감정 매핑
-            Dictionary<string, string>? emotionMap = null;
-            if (!string.IsNullOrWhiteSpace(voiceName))
-            {
-                var profile = VoiceCatalog.GetProfile(voiceName);
-                if (profile != null && profile.EmotionMap != null)
-                    emotionMap = profile.EmotionMap;
-            }
+            var emotionMap = GetEmotionMap(voiceId);
 
             if (matches.Count > 0)
             {
-                foreach (Match match in matches)
-                {
-                    if (match.Groups.Count >= 3)
-                    {
-                        var originalEmotion = match.Groups[1].Value.Trim();
-                        var mappedEmotion = emotionMap != null && emotionMap.ContainsKey(originalEmotion)
-                            ? emotionMap[originalEmotion]
-                            : originalEmotion;
-                        emotions.Add(mappedEmotion);
-                        texts.Add(match.Groups[2].Value.Trim());
-                    }
-                }
+                ProcessMatches(matches, emotionMap, segments, seenTexts);
             }
             else
             {
-                emotions.Add("neutral");
-                texts.Add(response);
+                var segment = ChatMessageSegment.CreateTextOnly(response, 0);
+                segment.Emotion = "neutral";
+                segments.Add(segment);
             }
 
-            return new ChatOutputFormatResult
+            return segments;
+        }
+
+        private Dictionary<string, string>? GetEmotionMap(string? voiceId)
+        {
+            if (string.IsNullOrWhiteSpace(voiceId))
+                return null;
+
+            var profile = VoiceCatalog.GetProfileById(voiceId);
+            return profile?.EmotionMap;
+        }
+
+        private void ProcessMatches(MatchCollection matches, Dictionary<string, string>? emotionMap, List<ChatMessageSegment> segments, HashSet<string> seenTexts)
+        {
+            for (int i = 0; i < matches.Count; i++)
             {
-                Response = response,
-                Emotion = emotions,
-                Text = texts
-            };
+                var match = matches[i];
+                if (match.Groups.Count >= 3)
+                {
+                    var originalEmotion = match.Groups[1].Value.Trim();
+                    var mappedEmotion = emotionMap != null && emotionMap.ContainsKey(originalEmotion)
+                        ? emotionMap[originalEmotion]
+                        : originalEmotion;
+                    var text = match.Groups[2].Value.Trim();
+                    
+                    if (!seenTexts.Contains(text))
+                    {
+                        seenTexts.Add(text);
+                        var segment = ChatMessageSegment.CreateTextOnly(text, segments.Count);
+                        segment.Emotion = mappedEmotion;
+                        segments.Add(segment);
+                    }
+                }
+            }
         }
     }
 }
diff --git a/ProjectVG.Application/Services/Chat/Factories/ILLMFormat.cs b/ProjectVG.Application/Services/Chat/Factories/ILLMFormat.cs
index 216aa65..3afe36c 100644
--- a/ProjectVG.Application/Services/Chat/Factories/ILLMFormat.cs
+++ b/ProjectVG.Application/Services/Chat/Factories/ILLMFormat.cs
@@ -8,6 +8,6 @@ public interface ILLMFormat<TInput, TOutput>
         float Temperature { get; }
         int MaxTokens { get; }
         TOutput Parse(string llmResponse, TInput input);
-        double CalculateCost(int tokensUsed);
+        double CalculateCost(int promptTokens, int completionTokens);
     }
 }
diff --git a/ProjectVG.Application/Services/Chat/Factories/UserInputAnalysisLLMFormat.cs b/ProjectVG.Application/Services/Chat/Factories/UserInputAnalysisLLMFormat.cs
index bb5af41..3590803 100644
--- a/ProjectVG.Application/Services/Chat/Factories/UserInputAnalysisLLMFormat.cs
+++ b/ProjectVG.Application/Services/Chat/Factories/UserInputAnalysisLLMFormat.cs
@@ -204,13 +204,10 @@ private UserInputAnalysis CreateDefaultValidResponse()
             return UserInputAnalysis.CreateValid("일반적인 대화", "대화", UserInputAction.Chat, new List<string>());
         }
 
-        public double CalculateCost(int tokensUsed)
+        public double CalculateCost(int promptTokens, int completionTokens)
         {
-            var inputCost = LLMModelInfo.GetInputCost(Model);
-            var outputCost = LLMModelInfo.GetOutputCost(Model);
-            
-            // 토큰 수를 백만 단위로 변환하여 비용 계산
-            return (tokensUsed / 1_000_000.0) * (inputCost + outputCost);
+            return LLMModelInfo.CalculateCost(Model, promptTokens, completionTokens);
         }
+
     }
 }
diff --git a/ProjectVG.Application/Services/Chat/Handlers/ChatFailureHandler.cs b/ProjectVG.Application/Services/Chat/Handlers/ChatFailureHandler.cs
new file mode 100644
index 0000000..d02d181
--- /dev/null
+++ b/ProjectVG.Application/Services/Chat/Handlers/ChatFailureHandler.cs
@@ -0,0 +1,48 @@
+using ProjectVG.Application.Models.Chat;
+using ProjectVG.Application.Models.WebSocket;
+using ProjectVG.Application.Services.WebSocket;
+using ProjectVG.Application.Services.Conversation;
+using ProjectVG.Infrastructure.Integrations.MemoryClient;
+using ProjectVG.Domain.Enums;
+
+namespace ProjectVG.Application.Services.Chat.Handlers
+{
+    public class ChatFailureHandler
+    {
+        private readonly ILogger<ChatFailureHandler> _logger;
+        private readonly IWebSocketManager _webSocketService;
+        private readonly IConversationService _conversationService;
+        private readonly IMemoryClient _memoryClient;
+
+        public ChatFailureHandler(
+            ILogger<ChatFailureHandler> logger,
+            IWebSocketManager webSocketService,
+            IConversationService conversationService,
+            IMemoryClient memoryClient)
+        {
+            _logger = logger;
+            _webSocketService = webSocketService;
+            _conversationService = conversationService;
+            _memoryClient = memoryClient;
+        }
+
+        public Task HandleFailureAsync(ChatProcessContext context, Exception exception)
+        {
+            _logger.LogError(exception, "채팅 처리 실패: 세션 {SessionId}", context.SessionId);
+            return SendErrorMessageAsync(context, "요청 처리 중 오류가 발생했습니다. 잠시 후 다시 시도해주세요.");
+        }
+
+        private async Task SendErrorMessageAsync(ChatProcessContext context, string errorMessage)
+        {
+            try
+            {
+                var errorResponse = new WebSocketMessage("error", new { message = errorMessage });
+                await _webSocketService.SendAsync(context.SessionId, errorResponse);
+            }
+            catch (Exception ex)
+            {
+                _logger.LogError(ex, "오류 메시지 전송 실패: 세션 {SessionId}", context.SessionId);
+            }
+        }
+    }
+}
diff --git a/ProjectVG.Application/Services/Chat/Preprocessors/UserInputAnalysisProcessor.cs b/ProjectVG.Application/Services/Chat/Preprocessors/UserInputAnalysisProcessor.cs
index 7266d33..adb69d6 100644
--- a/ProjectVG.Application/Services/Chat/Preprocessors/UserInputAnalysisProcessor.cs
+++ b/ProjectVG.Application/Services/Chat/Preprocessors/UserInputAnalysisProcessor.cs
@@ -41,10 +41,13 @@ public async Task<UserInputAnalysis> ProcessAsync(string userInput, IEnumerable<
                     temperature: format.Temperature
                 );
 
+                var cost = format.CalculateCost(llmResponse.InputTokens, llmResponse.OutputTokens);
                 var analysis = format.Parse(llmResponse.Response, userInput);
+                analysis.Cost = cost;
                 
-                _logger.LogDebug("사용자 입력 분석 완료: '{Input}' -> 맥락: {Context}, 의도: {Intent}, 액션: {Action}", 
-                    userInput, analysis.ConversationContext, analysis.UserIntent, analysis.Action);
+                Console.WriteLine($"[USER_INPUT_ANALYSIS_DEBUG] ID: {llmResponse.Id}, 입력 토큰: {llmResponse.InputTokens}, 출력 토큰: {llmResponse.OutputTokens}, 총 토큰: {llmResponse.TokensUsed}, 계산된 비용: {cost:F0} Cost");
+                _logger.LogDebug("사용자 입력 분석 완료: '{Input}' -> 맥락: {Context}, 의도: {Intent}, 액션: {Action}, 비용: {Cost}", 
+                    userInput, analysis.ConversationContext, analysis.UserIntent, analysis.Action, cost);
 
                 return analysis;
             }
diff --git a/ProjectVG.Application/Services/Chat/Processors/ChatLLMProcessor.cs b/ProjectVG.Application/Services/Chat/Processors/ChatLLMProcessor.cs
index a66c832..009879c 100644
--- a/ProjectVG.Application/Services/Chat/Processors/ChatLLMProcessor.cs
+++ b/ProjectVG.Application/Services/Chat/Processors/ChatLLMProcessor.cs
@@ -17,7 +17,7 @@ public ChatLLMProcessor(
             _logger = logger;
         }
 
-        public async Task<ChatProcessResult> ProcessAsync(ChatPreprocessContext context)
+        public async Task ProcessAsync(ChatProcessContext context)
         {
             var format = LLMFormatFactory.CreateChatFormat();
 
@@ -25,39 +25,21 @@ public async Task<ChatProcessResult> ProcessAsync(ChatPreprocessContext context)
                     format.GetSystemMessage(context),
                     context.UserMessage,
                     format.GetInstructions(context),
-                    context.ParseConversationHistory(),
-                    context.MemoryContext,
+                    context.ParseConversationHistory().ToList(),
+                    context.MemoryContext?.ToList(),
                     model: format.Model,
                     maxTokens: format.MaxTokens,
                     temperature: format.Temperature
                 );
 
-            // 결과 파싱
-            var parsed = format.Parse(llmResponse.Response, context);
-            var cost = format.CalculateCost(llmResponse.TokensUsed);
-            var segments = CreateSegments(parsed);
+            var segments = format.Parse(llmResponse.Response, context);
+            var cost = format.CalculateCost(llmResponse.InputTokens, llmResponse.OutputTokens);
 
-            _logger.LogDebug("LLM 처리 완료: 세션 {SessionId}, 토큰 {TokensUsed}, 비용 {Cost}",
-                context.SessionId, llmResponse.TokensUsed, cost);
+            Console.WriteLine($"[LLM_DEBUG] ID: {llmResponse.Id}, 입력 토큰: {llmResponse.InputTokens}, 출력 토큰: {llmResponse.OutputTokens}, 계산된 비용: {cost:F0} Cost");
+            _logger.LogDebug("LLM 처리 완료: 세션 {SessionId}, ID {Id}, 입력 토큰 {InputTokens}, 출력 토큰 {OutputTokens}, 비용 {Cost}",
+                context.SessionId, llmResponse.Id, llmResponse.InputTokens, llmResponse.OutputTokens, cost);
 
-            return new ChatProcessResult {
-                Response = parsed.Response,
-                Segments = segments,
-                TokensUsed = llmResponse.TokensUsed,
-                Cost = cost
-            };
-        }
-
-        private List<ChatMessageSegment> CreateSegments(ChatOutputFormatResult parsed)
-        {
-            var segments = new List<ChatMessageSegment>();
-            for (int i = 0; i < parsed.Text.Count; i++) {
-                var emotion = parsed.Emotion.Count > i ? parsed.Emotion[i] : "neutral";
-                var segment = ChatMessageSegment.CreateTextOnly(parsed.Text[i], i);
-                segment.Emotion = emotion;
-                segments.Add(segment);
-            }
-            return segments;
+            context.SetResponse(llmResponse.Response, segments, cost);
         }
     }
 }
diff --git a/ProjectVG.Application/Services/Chat/Processors/ChatResultProcessor.cs b/ProjectVG.Application/Services/Chat/Processors/ChatResultProcessor.cs
index 861eeb3..53fe599 100644
--- a/ProjectVG.Application/Services/Chat/Processors/ChatResultProcessor.cs
+++ b/ProjectVG.Application/Services/Chat/Processors/ChatResultProcessor.cs
@@ -26,18 +26,18 @@ public ChatResultProcessor(
             _webSocketService = webSocketService;
         }
 
-        public async Task PersistResultsAsync(ChatPreprocessContext context, ChatProcessResult result)
+        public async Task PersistResultsAsync(ChatProcessContext context)
         {
             await _conversationService.AddMessageAsync(context.UserId, context.CharacterId, ChatRole.User, context.UserMessage);
-            await _conversationService.AddMessageAsync(context.UserId, context.CharacterId, ChatRole.Assistant, result.Response);
-            await _memoryClient.AddMemoryAsync(context.MemoryStore, result.Response);
+            await _conversationService.AddMessageAsync(context.UserId, context.CharacterId, ChatRole.Assistant, context.Response);
+            await _memoryClient.AddMemoryAsync(context.MemoryStore, context.Response);
 
             _logger.LogDebug("채팅 결과 저장 완료: 세션 {SessionId}, 사용자 {UserId}", context.SessionId, context.UserId);
         }
 
-        public async Task SendResultsAsync(ChatPreprocessContext context, ChatProcessResult result)
+        public async Task SendResultsAsync(ChatProcessContext context)
         {
-            foreach (var segment in result.Segments.OrderBy(s => s.Order)) {
+            foreach (var segment in context.Segments.OrderBy(s => s.Order)) {
                 if (segment.IsEmpty) continue;
 
                 var integratedMessage = new IntegratedChatMessage {
@@ -55,7 +55,7 @@ public async Task SendResultsAsync(ChatPreprocessContext context, ChatProcessRes
             }
 
             _logger.LogDebug("채팅 결과 전송 완료: 세션 {SessionId}, 세그먼트 {SegmentCount}개",
-                context.SessionId, result.Segments.Count(s => !s.IsEmpty));
+                context.SessionId, context.Segments.Count(s => !s.IsEmpty));
         }
     }
 }
diff --git a/ProjectVG.Application/Services/Chat/Processors/ChatTTSProcessor.cs b/ProjectVG.Application/Services/Chat/Processors/ChatTTSProcessor.cs
index 3ccf9de..b758d20 100644
--- a/ProjectVG.Application/Services/Chat/Processors/ChatTTSProcessor.cs
+++ b/ProjectVG.Application/Services/Chat/Processors/ChatTTSProcessor.cs
@@ -17,172 +17,98 @@ public ChatTTSProcessor(
             _logger = logger;
         }
 
-        public async Task ProcessAsync(ChatPreprocessContext context, ChatProcessResult result)
+        public async Task ProcessAsync(ChatProcessContext context)
         {
-            if (ShouldSkipProcessing(context, result)) {
+            if (!context.UseTTS || string.IsNullOrWhiteSpace(context.Character?.VoiceId) || context.Segments?.Count == 0) {
+                _logger.LogDebug("TTS 처리 건너뜀: 세션 {SessionId}, TTS사용여부 {UseTTS}, 음성ID {VoiceId}, 세그먼트 수 {SegmentCount}",
+                    context.SessionId, context.UseTTS, context.Character?.VoiceId, context.Segments?.Count ?? 0);
                 return;
             }
 
-            var profile = GetVoiceProfile(context.VoiceName, context.SessionId);
+            var profile = VoiceCatalog.GetProfile(context.Character.VoiceId);
             if (profile == null) {
+                _logger.LogWarning("존재하지 않는 보이스: {VoiceId}, 세션 {SessionId}", context.Character.VoiceId, context.SessionId);
                 return;
             }
 
-            var ttsTasks = CreateTTSProcessingTasks(context, result, profile);
-            var ttsResults = await Task.WhenAll(ttsTasks);
-
-            ApplyTTSResultsToSegments(ttsResults, result);
-
-            LogProcessingCompletion(context.SessionId, ttsResults, result.Cost);
-        }
-
-        private bool ShouldSkipProcessing(ChatPreprocessContext context, ChatProcessResult result)
-        {
-            if (string.IsNullOrWhiteSpace(context.VoiceName) || result.Segments?.Count == 0) {
-                _logger.LogDebug("TTS 처리 건너뜀: 세션 {SessionId}, 음성명 {VoiceName}, 세그먼트 수 {SegmentCount}",
-                    context.SessionId, context.VoiceName, result.Segments?.Count ?? 0);
-                return true;
-            }
-            return false;
-        }
-
-        private VoiceProfile? GetVoiceProfile(string voiceName, string sessionId)
-        {
-            var profile = VoiceCatalog.GetProfile(voiceName);
-            if (profile == null) {
-                _logger.LogWarning("존재하지 않는 보이스: {VoiceName}, 세션 {SessionId}", voiceName, sessionId);
-            }
-            return profile;
-        }
-
-        private List<Task<(int idx, TextToSpeechResponse)>> CreateTTSProcessingTasks(
-            ChatPreprocessContext context,
-            ChatProcessResult result,
-            VoiceProfile profile)
-        {
             var ttsTasks = new List<Task<(int idx, TextToSpeechResponse)>>();
+            for (int i = 0; i < context.Segments.Count; i++) {
+                var segment = context.Segments[i];
+                if (!segment.HasText) continue;
 
-            for (int i = 0; i < result.Segments.Count; i++) {
+                var emotion = NormalizeEmotion(segment.Emotion, profile);
                 int idx = i;
-                var segment = result.Segments[idx];
+                ttsTasks.Add(Task.Run(async () => (idx, await GenerateTTSAsync(profile, segment.Text!, emotion))));
+            }
 
-                if (!segment.HasText) continue;
+            var ttsResults = await Task.WhenAll(ttsTasks);
+            var processedCount = 0;
 
-                var emotion = ValidateAndNormalizeEmotion(segment.Emotion, profile, context.VoiceName);
-                ttsTasks.Add(Task.Run(async () => (idx, await ProcessTTSAsync(profile, segment.Text!, emotion))));
+            foreach (var (idx, ttsResult) in ttsResults.OrderBy(x => x.idx)) {
+                if (ttsResult.Success == true && ttsResult.AudioData != null) {
+                    var segment = context.Segments[idx];
+                    segment.SetAudioData(ttsResult.AudioData, ttsResult.ContentType, ttsResult.AudioLength);
+                    
+                    if (ttsResult.AudioLength.HasValue) {
+                        var ttsCost = TTSCostInfo.CalculateTTSCost(ttsResult.AudioLength.Value);
+                        context.AddCost(ttsCost);
+                        Console.WriteLine($"[TTS_DEBUG] 오디오 길이: {ttsResult.AudioLength.Value:F2}초, TTS 비용: {ttsCost:F0} Cost");
+                    }
+                    processedCount++;
+                }
             }
 
-            return ttsTasks;
+            _logger.LogDebug("TTS 처리 완료: 세션 {SessionId}, 처리된 세그먼트 {ProcessedCount}개, 총 비용 {TotalCost}",
+                context.SessionId, processedCount, context.Cost);
         }
 
-        private string ValidateAndNormalizeEmotion(string? emotion, VoiceProfile profile, string voiceName)
+        private string NormalizeEmotion(string? emotion, VoiceProfile profile)
         {
             var normalizedEmotion = emotion ?? "neutral";
-
             if (!profile.SupportedStyles.Contains(normalizedEmotion)) {
-                _logger.LogWarning("보이스 '{VoiceName}'는 '{Emotion}' 스타일을 지원하지 않습니다. 기본값 사용.",
-                    voiceName, normalizedEmotion);
+                _logger.LogWarning("보이스 '{VoiceId}'는 '{Emotion}' 스타일을 지원하지 않습니다. 기본값 사용.",
+                    profile.VoiceId, normalizedEmotion);
                 return "neutral";
             }
-
             return normalizedEmotion;
         }
 
-        private void ApplyTTSResultsToSegments(
-            (int idx, TextToSpeechResponse)[] ttsResults,
-            ChatProcessResult result)
-        {
-            foreach (var (idx, ttsResult) in ttsResults.OrderBy(x => x.idx)) {
-                if (IsValidTTSResult(ttsResult)) {
-                    ApplyTTSResultToSegment(result.Segments[idx], ttsResult);
-                    UpdateCost(result, ttsResult);
-                }
-            }
-        }
-
-        private bool IsValidTTSResult(TextToSpeechResponse ttsResult)
-        {
-            return ttsResult.Success == true && ttsResult.AudioData != null;
-        }
-
-        private void ApplyTTSResultToSegment(ChatMessageSegment segment, TextToSpeechResponse ttsResult)
-        {
-            segment.AudioData = ttsResult.AudioData;
-            segment.AudioContentType = ttsResult.ContentType;
-            segment.AudioLength = ttsResult.AudioLength;
-        }
-
-        private void UpdateCost(ChatProcessResult result, TextToSpeechResponse ttsResult)
-        {
-            if (ttsResult.AudioLength.HasValue) {
-                result.Cost += Math.Ceiling(ttsResult.AudioLength.Value / 0.1);
-            }
-        }
-
-        private void LogProcessingCompletion(string sessionId, (int idx, TextToSpeechResponse)[] ttsResults, double totalCost)
-        {
-            var processedCount = ttsResults.Count(r => r.Item2.Success);
-            _logger.LogDebug("TTS 처리 완료: 세션 {SessionId}, 처리된 세그먼트 {ProcessedCount}개, 총 비용 {TotalCost}",
-                sessionId, processedCount, totalCost);
-        }
-
-        private async Task<TextToSpeechResponse> ProcessTTSAsync(VoiceProfile profile, string text, string emotion)
+        private async Task<TextToSpeechResponse> GenerateTTSAsync(VoiceProfile profile, string text, string emotion)
         {
             var startTime = DateTime.UtcNow;
 
             try {
-                ValidateText(text);
-                var request = CreateTTSRequest(profile, text, emotion);
+                if (string.IsNullOrWhiteSpace(text))
+                    throw new ValidationException(ErrorCode.MESSAGE_EMPTY, "텍스트가 비어있습니다.");
+                if (text.Length > 300)
+                    throw new ValidationException(ErrorCode.MESSAGE_TOO_LONG, "텍스트는 300자를 초과할 수 없습니다.");
+
+                var request = new TextToSpeechRequest {
+                    Text = text,
+                    Language = profile.DefaultLanguage,
+                    Emotion = emotion,
+                    VoiceSettings = new VoiceSettings(),
+                    VoiceId = profile.VoiceId
+                };
+
                 var response = await _ttsClient.TextToSpeechAsync(request);
 
-                LogTTSProcessingTime(startTime, response.AudioLength);
+                var endTime = DateTime.UtcNow;
+                var processingTime = (endTime - startTime).TotalMilliseconds;
+                _logger.LogInformation("[TTS] 응답 생성 완료: 오디오 길이 ({AudioLength:F2}초), 요청 시간({ProcessingTimeMs:F2}ms)",
+                    response.AudioLength, processingTime);
+
                 return response;
             }
             catch (ValidationException vex) {
                 _logger.LogWarning(vex, "[TTS] 요청 검증 실패");
-                return CreateErrorResponse(vex.Message);
+                return new TextToSpeechResponse { Success = false, ErrorMessage = vex.Message };
             }
             catch (Exception ex) {
                 _logger.LogError(ex, "[TTS] TTS 서비스 오류 발생");
-                return CreateErrorResponse(ex.Message);
+                return new TextToSpeechResponse { Success = false, ErrorMessage = ex.Message };
             }
         }
-
-        private TextToSpeechRequest CreateTTSRequest(VoiceProfile profile, string text, string emotion)
-        {
-            return new TextToSpeechRequest {
-                Text = text,
-                Language = profile.DefaultLanguage,
-                Emotion = emotion,
-                VoiceSettings = new VoiceSettings(),
-                VoiceId = profile.VoiceId
-            };
-        }
-
-        private void LogTTSProcessingTime(DateTime startTime, double? audioLength)
-        {
-            var endTime = DateTime.UtcNow;
-            var processingTime = (endTime - startTime).TotalMilliseconds;
-
-            _logger.LogInformation("[TTS] 응답 생성 완료: 오디오 길이 ({AudioLength:F2}초), 요청 시간({ProcessingTimeMs:F2}ms)",
-                audioLength, processingTime);
-        }
-
-        private TextToSpeechResponse CreateErrorResponse(string errorMessage)
-        {
-            return new TextToSpeechResponse {
-                Success = false,
-                ErrorMessage = errorMessage
-            };
-        }
-
-        private void ValidateText(string text)
-        {
-            if (string.IsNullOrWhiteSpace(text))
-                throw new ValidationException(ErrorCode.MESSAGE_EMPTY, "텍스트가 비어있습니다.");
-            if (text.Length > 300)
-                throw new ValidationException(ErrorCode.MESSAGE_TOO_LONG, "텍스트는 300자를 초과할 수 없습니다.");
-        }
     }
 }
 
diff --git a/ProjectVG.Common/Constants/LLMModelInfo.cs b/ProjectVG.Common/Constants/LLMModelInfo.cs
index b97d9b4..18f0b0f 100644
--- a/ProjectVG.Common/Constants/LLMModelInfo.cs
+++ b/ProjectVG.Common/Constants/LLMModelInfo.cs
@@ -2,6 +2,9 @@ namespace ProjectVG.Common.Constants
 {
     public static class LLMModelInfo
     {
+        private const double TOKENS_PER_MILLION = 1_000_000.0;
+        private const double MILLICENTS_PER_DOLLAR = 100_000.0;
+        private const double COST_CALCULATION_FACTOR = TOKENS_PER_MILLION / MILLICENTS_PER_DOLLAR;
         public static class GPT5
         {
             public const string Name = "gpt-5";
@@ -246,7 +249,7 @@ public static double GetInputCost(string model)
                 O3.Name => O3.Price.Input,
                 GPT35Turbo.Name => GPT35Turbo.Price.Input,
                 GPT4.Name => GPT4.Price.Input,
-                _ => GPT4oMini.Price.Input // 기본값
+                _ => GPT4oMini.Price.Input
             };
         }
 
@@ -274,10 +277,20 @@ public static double GetOutputCost(string model)
                 O3.Name => O3.Price.Output,
                 GPT35Turbo.Name => GPT35Turbo.Price.Output,
                 GPT4.Name => GPT4.Price.Output,
-                _ => GPT4oMini.Price.Output // 기본값
+                _ => GPT4oMini.Price.Output
             };
         }
 
+        public static double GetInputCostPerToken(string model)
+        {
+            return GetInputCost(model) / COST_CALCULATION_FACTOR;
+        }
+
+        public static double GetOutputCostPerToken(string model)
+        {
+            return GetOutputCost(model) / COST_CALCULATION_FACTOR;
+        }
+
         public static double GetCachedInputCost(string model)
         {
             return model switch
@@ -295,8 +308,19 @@ public static double GetCachedInputCost(string model)
                 GPT4oMiniRealtimePreview.Name => GPT4oMiniRealtimePreview.Price.CachedInput,
                 O1.Name => O1.Price.CachedInput,
                 O3.Name => O3.Price.CachedInput,
-                _ => GetInputCost(model) * 0.1 // 기본적으로 입력 비용의 10%
+                _ => GetInputCost(model) * 0.1
             };
         }
+
+        public static double CalculateCost(string model, int promptTokens, int completionTokens)
+        {
+            var inputCostPerToken = GetInputCostPerToken(model);
+            var outputCostPerToken = GetOutputCostPerToken(model);
+            
+            var inputCostTotal = Math.Ceiling(promptTokens * inputCostPerToken);
+            var outputCostTotal = Math.Ceiling(completionTokens * outputCostPerToken);
+            
+            return inputCostTotal + outputCostTotal;
+        }
     }
 }
diff --git a/ProjectVG.Common/Constants/TTSCostInfo.cs b/ProjectVG.Common/Constants/TTSCostInfo.cs
new file mode 100644
index 0000000..0000e19
--- /dev/null
+++ b/ProjectVG.Common/Constants/TTSCostInfo.cs
@@ -0,0 +1,21 @@
+namespace ProjectVG.Common.Constants
+{
+    public static class TTSCostInfo
+    {
+        private const double TTS_CREDITS_PER_DOLLAR = 100_000.0;
+        private const double TTS_CREDITS_PER_SECOND = 10.0;
+        private const double MILLICENTS_PER_DOLLAR = 100_000.0;
+        private const double TTS_COST_PER_SECOND = TTS_CREDITS_PER_SECOND / TTS_CREDITS_PER_DOLLAR * MILLICENTS_PER_DOLLAR;
+
+        public static double GetTTSCostPerSecond()
+        {
+            return TTS_COST_PER_SECOND;
+        }
+
+        public static double CalculateTTSCost(double durationInSeconds)
+        {
+            var roundedDuration = Math.Ceiling(durationInSeconds * 10) / 10.0;
+            return Math.Ceiling(roundedDuration * TTS_COST_PER_SECOND);
+        }
+    }
+}
diff --git a/ProjectVG.Infrastructure/Integrations/LLMClient/LLMClient.cs b/ProjectVG.Infrastructure/Integrations/LLMClient/LLMClient.cs
index d731729..e71e281 100644
--- a/ProjectVG.Infrastructure/Integrations/LLMClient/LLMClient.cs
+++ b/ProjectVG.Infrastructure/Integrations/LLMClient/LLMClient.cs
@@ -79,8 +79,11 @@ public async Task<LLMResponse> SendRequestAsync(LLMRequest request)
                 return new LLMResponse
                 {
                     Success = true,
+                    Id = "mock-chatcmpl-" + Guid.NewGuid().ToString("N")[..8],
                     Response = "안녕하세요! 저는 현재 Mock 모드로 동작하고 있습니다. 실제 LLM 서비스가 연결되지 않았습니다.",
                     TokensUsed = 50,
+                    InputTokens = 30,
+                    OutputTokens = 20,
                     ResponseTime = 100
                 };
             }
diff --git a/ProjectVG.Infrastructure/Integrations/LLMClient/Models/LLMResponse.cs b/ProjectVG.Infrastructure/Integrations/LLMClient/Models/LLMResponse.cs
index c2aa3ee..9740499 100644
--- a/ProjectVG.Infrastructure/Integrations/LLMClient/Models/LLMResponse.cs
+++ b/ProjectVG.Infrastructure/Integrations/LLMClient/Models/LLMResponse.cs
@@ -4,6 +4,12 @@ namespace ProjectVG.Infrastructure.Integrations.LLMClient.Models
 {
     public class LLMResponse
     {
+        /// <summary>
+        /// OpenAI API 응답 ID
+        /// </summary>
+        [JsonPropertyName("id")]
+        public string Id { get; set; } = default!;
+
         /// <summary>
         /// 세션 ID
         /// </summary>
@@ -17,11 +23,23 @@ public class LLMResponse
         public string Response { get; set; } = default!;
 
         /// <summary>
-        /// 사용된 토큰 수
+        /// 사용된 토큰 수 (총합)
         /// </summary>
         [JsonPropertyName("total_tokens_used")]
         public int TokensUsed { get; set; }
 
+        /// <summary>
+        /// 입력 토큰 수 (input_tokens)
+        /// </summary>
+        [JsonPropertyName("input_tokens")]
+        public int InputTokens { get; set; }
+
+        /// <summary>
+        /// 출력 토큰 수 (output_tokens)
+        /// </summary>
+        [JsonPropertyName("output_tokens")]
+        public int OutputTokens { get; set; }
+
         /// <summary>
         /// 처리 시간 (ms)
         /// </summary>