diff --git a/AyCode.Services.Server.Tests/SignalRs/SignalRTestHelper.cs b/AyCode.Services.Server.Tests/SignalRs/SignalRTestHelper.cs
index d28015e..af811ee 100644
--- a/AyCode.Services.Server.Tests/SignalRs/SignalRTestHelper.cs
+++ b/AyCode.Services.Server.Tests/SignalRs/SignalRTestHelper.cs
@@ -1,7 +1,5 @@
 using AyCode.Core.Extensions;
 using AyCode.Services.SignalRs;
-using MessagePack;
-using MessagePack.Resolvers;
 
 namespace AyCode.Services.Server.Tests.SignalRs;
 
@@ -36,13 +34,9 @@ public enum SendTarget
 /// </summary>
 public static class SignalRTestHelper
 {
-    private static readonly MessagePackSerializerOptions MessagePackOptions = ContractlessStandardResolver.Options;
-
     public static byte[] CreatePrimitiveParamsMessage(params object[] values)
     {
-        var idMessage = new IdMessage(values);
-        var postMessage = new SignalPostJsonDataMessage<IdMessage>(idMessage);
-        return MessagePackSerializer.Serialize(postMessage, MessagePackOptions);
+        return SignalRSerializationHelper.SerializeParametersToBinary(values);
     }
 
     public static byte[] CreateSinglePrimitiveMessage<T>(T value) where T : notnull
@@ -50,22 +44,19 @@ public static class SignalRTestHelper
 
     public static byte[] CreateComplexObjectMessage<T>(T obj)
     {
-        var json = obj.ToJson();
-        var postMessage = new SignalPostJsonDataMessage<object>(json);
-        return MessagePackSerializer.Serialize(postMessage, MessagePackOptions);
+        return SignalRSerializationHelper.SerializeParametersToBinary(new object[] { obj! });
     }
 
     public static byte[] CreateEmptyMessage()
     {
-        var postMessage = new SignalPostJsonDataMessage<object>();
-        return MessagePackSerializer.Serialize(postMessage, MessagePackOptions);
+        return SignalRSerializationHelper.SerializeParametersToBinary(Array.Empty<object>());
     }
 
     public static T? GetResponseData<T>(SentMessage sentMessage)
     {
         if (sentMessage.Message is SignalResponseDataMessage dataResponse && dataResponse.ResponseData != null)
             return dataResponse.GetResponseData<T>();
-        
+
         return default;
     }
 
@@ -73,10 +64,10 @@ public static class SignalRTestHelper
     {
         if (sentMessage.Message is not SignalResponseDataMessage response)
             throw new AssertFailedException($"Response is not SignalResponseDataMessage. Type: {sentMessage.Message.GetType().Name}");
-        
+
         if (response.Status != SignalResponseStatus.Success)
             throw new AssertFailedException($"Expected Success status but got {response.Status}");
-        
+
         if (sentMessage.MessageTag != expectedTag)
             throw new AssertFailedException($"Expected tag {expectedTag} but got {sentMessage.MessageTag}");
     }
@@ -85,10 +76,10 @@ public static class SignalRTestHelper
     {
         if (sentMessage.Message is not SignalResponseDataMessage response)
             throw new AssertFailedException($"Response is not SignalResponseDataMessage. Type: {sentMessage.Message.GetType().Name}");
-        
+
         if (response.Status != SignalResponseStatus.Error)
             throw new AssertFailedException($"Expected Error status but got {response.Status}");
-        
+
         if (sentMessage.MessageTag != expectedTag)
             throw new AssertFailedException($"Expected tag {expectedTag} but got {sentMessage.MessageTag}");
     }
diff --git a/AyCode.Services.Server/SignalRs/AcSignalRSendToClientService.cs b/AyCode.Services.Server/SignalRs/AcSignalRSendToClientService.cs
index 69a37f7..4abe5a5 100644
--- a/AyCode.Services.Server/SignalRs/AcSignalRSendToClientService.cs
+++ b/AyCode.Services.Server/SignalRs/AcSignalRSendToClientService.cs
@@ -16,7 +16,11 @@ public abstract class AcSignalRSendToClientService<TSignalRHub, TSignalRTags, TL
     protected virtual async Task SendMessageToClient(IAcSignalRHubItemServer sendTo, int messageTag, object? content)
     {
         var responseData = SignalRSerializationHelper.CreateResponseData(content, AcBinarySerializerOptions.Default) ?? [];
-        var receiveParams = new SignalReceiveParams { Status = SignalResponseStatus.Success };
+        var receiveParams = new SignalReceiveParams
+        {
+            Status = SignalResponseStatus.Success,
+            DataSerializerType = AyCode.Core.Serializers.AcSerializerType.Binary
+        };
 
         Logger.Info($"[{responseData.Length / 1024}kb] Server sending to client; {ConstHelper.NameByValue<TSignalRTags>(messageTag)}");
         await sendTo.OnReceiveMessage(messageTag, null, receiveParams, responseData);
diff --git a/AyCode.Services.Server/SignalRs/AcWebSignalRHubBase.cs b/AyCode.Services.Server/SignalRs/AcWebSignalRHubBase.cs
index f58839b..493f6bd 100644
--- a/AyCode.Services.Server/SignalRs/AcWebSignalRHubBase.cs
+++ b/AyCode.Services.Server/SignalRs/AcWebSignalRHubBase.cs
@@ -421,7 +421,8 @@ public abstract class AcWebSignalRHubBase<TSignalRTags, TLogger>(IConfiguration
     }
 
     /// <summary>
-    /// Deserializes parameters from the message based on method signature.
+    /// Deserializes parameters from the binary message based on method signature.
+    /// The message is a binary-serialized object[] from the client.
     /// Supports optional parameters with default values.
     /// </summary>
     private static object[]? DeserializeParameters(byte[]? message, AcMethodInfoModel<SignalRAttribute> methodInfoModel, string tagName, string methodName)
@@ -430,87 +431,15 @@ public abstract class AcWebSignalRHubBase<TSignalRTags, TLogger>(IConfiguration
         if (paramInfos is not { Length: > 0 })
             return null;
 
-        // Handle case where message is null/empty but all parameters have default values
         if (message is null or { Length: 0 })
         {
-            // Check if all parameters have default values
             if (paramInfos.All(p => p.HasDefaultValue))
-            {
-                // Return default values for all parameters
                 return paramInfos.Select(p => p.DefaultValue).ToArray();
-            }
-            
+
             throw new ArgumentException($"Message is null or empty but method '{methodName}' requires parameters; {tagName}");
         }
 
-        var msgBase = SignalRSerializationHelper.DeserializeFromBinary<SignalPostJsonMessage>(message);
-        if (string.IsNullOrEmpty(msgBase?.PostDataJson))
-        {
-            // Check if all parameters have default values
-            if (paramInfos.All(p => p.HasDefaultValue))
-            {
-                return paramInfos.Select(p => p.DefaultValue).ToArray();
-            }
-            
-            throw new ArgumentException($"Failed to deserialize message for method '{methodName}'; {tagName}");
-        }
-
-        var json = msgBase.PostDataJson;
-        var paramValues = new object?[paramInfos.Length];
-
-        // IdMessage format: multiple parameters as JSON array
-        if (json.Contains("\"Ids\""))
-        {
-            var idMessage = json.JsonTo<IdMessage>();
-            var providedCount = idMessage?.Ids?.Count ?? 0;
-
-            for (var i = 0; i < paramInfos.Length; i++)
-            {
-                var param = paramInfos[i];
-                
-                if (i < providedCount)
-                {
-                    paramValues[i] = AcJsonDeserializer.Deserialize(idMessage!.Ids![i], param.ParameterType);
-                }
-                else if (param.HasDefaultValue)
-                {
-                    paramValues[i] = param.DefaultValue;
-                }
-                else
-                {
-                    throw new ArgumentException($"Missing required parameter '{param.Name}' for method '{methodName}'; {tagName}");
-                }
-            }
-        }
-        else
-        {
-            // Single complex object format
-            paramValues[0] = json.JsonTo(paramInfos[0].ParameterType);
-
-            // Fill remaining parameters with defaults
-            for (var i = 1; i < paramInfos.Length; i++)
-            {
-                var param = paramInfos[i];
-                if (param.HasDefaultValue)
-                {
-                    paramValues[i] = param.DefaultValue;
-                }
-                else
-                {
-                    throw new ArgumentException($"Missing required parameter '{param.Name}' for method '{methodName}'; {tagName}");
-                }
-            }
-        }
-
-        return paramValues!;
-    }
-
-    /// <summary>
-    /// Determines if a type should use IdMessage format.
-    /// </summary>
-    private static bool IsPrimitiveOrStringOrEnum(Type type)
-    {
-        return type == typeof(string) || type.IsEnum || type.IsValueType || type == typeof(DateTime);
+        return SignalRSerializationHelper.DeserializeParametersFromBinary(message, paramInfos);
     }
 
     #endregion
@@ -547,7 +476,11 @@ public abstract class AcWebSignalRHubBase<TSignalRTags, TLogger>(IConfiguration
     protected virtual async Task SendMessageToClient(IAcSignalRHubItemServer sendTo, int messageTag, ISignalRMessage message, int? requestId = null)
     {
         var responseMessage = (SignalResponseDataMessage)message;
-        var receiveParams = new SignalReceiveParams { Status = responseMessage.Status };
+        var receiveParams = new SignalReceiveParams
+        {
+            Status = responseMessage.Status,
+            DataSerializerType = responseMessage.DataSerializerType
+        };
         var responseData = responseMessage.ResponseData ?? [];
 
         var tagName = ConstHelper.NameByValue<TSignalRTags>(messageTag);
diff --git a/AyCode.Services.Server/docs/SIGNALR_SERVER.md b/AyCode.Services.Server/docs/SIGNALR_SERVER.md
index 30e6252..3d1e8db 100644
--- a/AyCode.Services.Server/docs/SIGNALR_SERVER.md
+++ b/AyCode.Services.Server/docs/SIGNALR_SERVER.md
@@ -10,14 +10,15 @@ Server-side SignalR hub infrastructure: method dispatch, session management, bro
 ```
 6. OnReceiveMessage(tag, requestId, receiveParams, data)
 7. DynamicMethodRegistry.GetMethodByMessageTag(tag)      ← ConcurrentDictionary lookup
-8. DeserializeParameters(data):
-   ├─ DeserializeFromBinary<SignalPostJsonMessage>()     ← unwrap Binary envelope
-   ├─ IdMessage format? → parse each Ids[i] as JSON per parameter type
-   └─ Complex object? → json.JsonTo(paramType)           ⚠️ tech debt: JSON parse
+8. DeserializeParameters(data, methodInfoModel):
+   ├─ null/empty + all defaults? → default values array
+   └─ DeserializeParametersFromBinary(data, paramInfos)
+      Each param: [INT32 len][AcBinary bytes] → BinaryTo(targetType)
+      Type-guided: target type from ParameterInfo[] (method signature)
 9. MethodInfo.InvokeMethod(instance, params)              ← unwraps Task/ValueTask
 10. CreateResponseMessage(tag, Success, result)           ← Binary serialize payload → byte[]
 11. SendMessageToClient(caller, tag, message, requestId):
-    ├─ Extract receiveParams { Status } + responseData byte[] from message
+    ├─ Extract receiveParams { Status, DataSerializerType } + responseData byte[] from message
     └─ caller.OnReceiveMessage(tag, requestId, receiveParams, responseData)
         (metadata + payload as separate args — no envelope serialization)
 12. If SendToOtherClientType != None:
diff --git a/AyCode.Services.Tests/SignalRs/PostJsonDataMessageTests.cs b/AyCode.Services.Tests/SignalRs/PostJsonDataMessageTests.cs
index 46be20a..1b32396 100644
--- a/AyCode.Services.Tests/SignalRs/PostJsonDataMessageTests.cs
+++ b/AyCode.Services.Tests/SignalRs/PostJsonDataMessageTests.cs
@@ -1,5 +1,4 @@
-using AyCode.Core.Extensions;
-using AyCode.Core.Serializers.Jsons;
+using AyCode.Core.Extensions;
 using AyCode.Services.SignalRs;
 
 namespace AyCode.Services.Tests.SignalRs;
@@ -8,99 +7,96 @@ namespace AyCode.Services.Tests.SignalRs;
 public class PostJsonDataMessageTests
 {
     [TestMethod]
-    public void Debug_CreatePostMessage_ForInt()
+    public void Debug_ParameterBinary_RoundTrip_ForInt()
     {
-        var message = CreatePostMessageTest(42);
+        var parameters = new object[] { 42 };
+        Console.WriteLine($"Parameters: [{string.Join(", ", parameters)}]");
 
-        Console.WriteLine($"Message type: {message.GetType().Name}");
-
-        if (message is SignalPostJsonDataMessage<IdMessage> idMsg)
-        {
-            Console.WriteLine($"PostDataJson: {idMsg.PostDataJson}");
-            Console.WriteLine($"PostData.Ids.Count: {idMsg.PostData.Ids.Count}");
-            Console.WriteLine($"PostData.Ids[0]: {idMsg.PostData.Ids[0]}");
-        }
-
-        var bytes = message.ToBinary();
+        var bytes = SignalRSerializationHelper.SerializeParametersToBinary(parameters);
         Console.WriteLine($"Binary bytes: {bytes.Length}");
 
-        var deserialized = bytes.BinaryTo<SignalPostJsonDataMessage<IdMessage>>();
-        Console.WriteLine($"Deserialized PostDataJson: {deserialized?.PostDataJson}");
-        Console.WriteLine($"Deserialized PostData type: {deserialized?.PostData?.GetType().Name}");
-        Console.WriteLine($"Deserialized PostData.Ids.Count: {deserialized?.PostData?.Ids.Count}");
+        // Simulate server deserialization with known target types
+        var paramInfos = typeof(PostJsonDataMessageTests)
+            .GetMethod(nameof(DummyIntMethod))!.GetParameters();
+        var deserialized = SignalRSerializationHelper.DeserializeParametersFromBinary(bytes, paramInfos);
 
-        Assert.IsNotNull(deserialized?.PostData);
-        Assert.AreEqual(1, deserialized.PostData.Ids.Count);
+        Assert.IsNotNull(deserialized);
+        Assert.AreEqual(1, deserialized.Length);
+        Assert.AreEqual(42, deserialized[0]);
     }
 
     [TestMethod]
     [DataRow(42)]
     [DataRow("45")]
     [DataRow(true)]
-    public void IdMessage_FullRoundTrip_AnyParameter(object testValue)
+    public void ParameterBinary_FullRoundTrip_AnyParameter(object testValue)
     {
-        dynamic GetValueByType(object value)
-        {
-            if (value is int valueInt) return valueInt;
-            if (value is bool valueBool) return valueBool;
-            if (value is string valueString) return valueString;
-
-            Assert.Fail($"Type of testValue not implemented");
-            return null;
-        }
-
-        Console.WriteLine("=== Step 1: Client creates message ===");
-        var idMessage = new IdMessage(GetValueByType(testValue));
-        Console.WriteLine($"IdMessage.Ids[0]: '{idMessage.Ids[0]}'");
-
-        var clientMessage = new SignalPostJsonDataMessage<IdMessage>(idMessage);
-        Console.WriteLine($"Client PostDataJson: '{clientMessage.PostDataJson}'");
+        Console.WriteLine("=== Step 1: Client creates object[] ===");
+        var parameters = new[] { testValue };
 
         Console.WriteLine("\n=== Step 2: Binary serialization ===");
-        var bytes = clientMessage.ToBinary();
+        var bytes = SignalRSerializationHelper.SerializeParametersToBinary(parameters);
         Console.WriteLine($"Binary bytes: {bytes.Length}");
 
-        Console.WriteLine("\n=== Step 3: Server deserializes ===");
-        var serverMessage = bytes.BinaryTo<SignalPostJsonDataMessage<IdMessage>>();
-        Console.WriteLine($"Server PostDataJson: '{serverMessage?.PostDataJson}'");
-        Console.WriteLine($"Server PostData.Ids.Count: {serverMessage?.PostData?.Ids.Count}");
-        Console.WriteLine($"Server PostData.Ids[0]: '{serverMessage?.PostData?.Ids[0]}'");
+        Console.WriteLine("\n=== Step 3: Server deserializes with target type ===");
+        var paramInfos = new[] { GetParamInfoForType(testValue.GetType()) };
+        var serverParams = SignalRSerializationHelper.DeserializeParametersFromBinary(bytes, paramInfos);
 
-        Console.WriteLine("\n=== Step 4: Server deserializes parameter ===");
-        var paramJson = serverMessage!.PostData.Ids[0];
-        Console.WriteLine($"Parameter JSON: '{paramJson}'");
-        var paramValue = AcJsonDeserializer.Deserialize(paramJson, testValue.GetType());
-        Console.WriteLine($"Deserialized value: {paramValue}");
+        Console.WriteLine($"Server params[0]: '{serverParams[0]}' (type: {serverParams[0]?.GetType().Name})");
 
-        Console.WriteLine("\n=== Step 5: Service method returns ===");
-        var serviceResult = $"{paramValue}";
+        Console.WriteLine("\n=== Step 4: Service method uses parameter ===");
+        var serviceResult = $"{serverParams![0]}";
         Console.WriteLine($"Service result: '{serviceResult}'");
 
-        Console.WriteLine("\n=== Step 6: Server creates response ===");
-        var response = new SignalResponseDataMessage(100, SignalResponseStatus.Success, serviceResult, AcJsonSerializerOptions.Default);
-        Console.WriteLine($"Response created with Binary bytes: {response.ResponseData?.Length ?? 0}");
+        Console.WriteLine("\n=== Step 5: Server creates response ===");
+        var response = new SignalResponseDataMessage(100, SignalResponseStatus.Success, serviceResult, AyCode.Core.Serializers.Binaries.AcBinarySerializerOptions.Default);
 
-        Console.WriteLine("\n=== Step 7: Response Binary ===");
+        Console.WriteLine("\n=== Step 6: Response Binary ===");
         var responseBytes = response.ToBinary();
-        Console.WriteLine($"Response Binary bytes: {responseBytes.Length}");
 
-        Console.WriteLine("\n=== Step 8: Client deserializes response ===");
+        Console.WriteLine("\n=== Step 7: Client deserializes response ===");
         var clientResponse = responseBytes.BinaryTo<SignalResponseDataMessage>();
-        Console.WriteLine($"Client Response Status: {clientResponse?.Status}");
 
-        Console.WriteLine("\n=== Step 9: Client deserializes to string ===");
+        Console.WriteLine("\n=== Step 8: Client deserializes to string ===");
         var finalResult = clientResponse?.GetResponseData<string>();
         Console.WriteLine($"Final result: '{finalResult}'");
-        Assert.AreEqual(GetValueByType(testValue).ToString(), finalResult);
+        Assert.AreEqual(testValue.ToString(), finalResult);
     }
 
-    private static ISignalRMessage CreatePostMessageTest<TPostData>(TPostData postData)
+    [TestMethod]
+    public void ParameterBinary_MultipleParams_RoundTrip()
     {
-        var type = typeof(TPostData);
+        var guid = Guid.NewGuid();
+        var parameters = new object[] { 42, "hello", true, guid };
 
-        if (type == typeof(string) || type.IsEnum || type.IsValueType || type == typeof(DateTime))
-            return new SignalPostJsonDataMessage<IdMessage>(new IdMessage(postData!));
+        var bytes = SignalRSerializationHelper.SerializeParametersToBinary(parameters);
 
-        return new SignalPostJsonDataMessage<TPostData>(postData);
-    }    
-}
\ No newline at end of file
+        var paramInfos = typeof(PostJsonDataMessageTests)
+            .GetMethod(nameof(DummyMultiMethod))!.GetParameters();
+        var deserialized = SignalRSerializationHelper.DeserializeParametersFromBinary(bytes, paramInfos);
+
+        Assert.IsNotNull(deserialized);
+        Assert.AreEqual(4, deserialized.Length);
+        Assert.AreEqual(42, deserialized[0]);
+        Assert.AreEqual("hello", deserialized[1]);
+        Assert.AreEqual(true, deserialized[2]);
+        Assert.AreEqual(guid, deserialized[3]);
+    }
+
+    // Dummy methods for ParameterInfo extraction
+    public static void DummyIntMethod(int value) { }
+    public static void DummyMultiMethod(int a, string b, bool c, Guid d) { }
+
+    private static System.Reflection.ParameterInfo GetParamInfoForType(Type type)
+    {
+        // Find a dummy method with the matching parameter type
+        if (type == typeof(int)) return typeof(PostJsonDataMessageTests).GetMethod(nameof(DummyInt))!.GetParameters()[0];
+        if (type == typeof(string)) return typeof(PostJsonDataMessageTests).GetMethod(nameof(DummyString))!.GetParameters()[0];
+        if (type == typeof(bool)) return typeof(PostJsonDataMessageTests).GetMethod(nameof(DummyBool))!.GetParameters()[0];
+        throw new NotSupportedException($"No dummy method for type {type.Name}");
+    }
+
+    public static void DummyInt(int v) { }
+    public static void DummyString(string v) { }
+    public static void DummyBool(bool v) { }
+}
diff --git a/AyCode.Services/SignalRs/AcSignalRClientBase.cs b/AyCode.Services/SignalRs/AcSignalRClientBase.cs
index bfeb4d5..d35065c 100644
--- a/AyCode.Services/SignalRs/AcSignalRClientBase.cs
+++ b/AyCode.Services/SignalRs/AcSignalRClientBase.cs
@@ -134,15 +134,15 @@ namespace AyCode.Services.SignalRs
         }
 
         public virtual Task SendMessageToServerAsync(int messageTag)
-            => SendMessageToServerAsync(messageTag, null, GetNextRequestId());
+            => SendMessageToServerAsync(messageTag, (object[]?)null, GetNextRequestId());
 
-        public virtual async Task SendMessageToServerAsync(int messageTag, ISignalRMessage? message, int? requestId)
+        public virtual async Task SendMessageToServerAsync(int messageTag, object[]? parameters, int? requestId)
         {
             Logger.DebugConditional($"Client SendMessageToServerAsync sending; {nameof(requestId)}: {requestId}; ConnectionState: {GetConnectionState()}; {ConstHelper.NameByValue(TagsName, messageTag)}");
 
             await StartConnection();
 
-            var msgBytes = message != null ? SignalRSerializationHelper.SerializeToBinary(message) : null;
+            var msgBytes = parameters is { Length: > 0 } ? SignalRSerializationHelper.SerializeParametersToBinary(parameters) : null;
 
             if (!IsConnected())
             {
@@ -157,10 +157,10 @@ namespace AyCode.Services.SignalRs
         #region CRUD
 
         public virtual Task<TResponseData?> PostAsync<TResponseData>(int messageTag, object parameter)
-            => SendMessageToServerAsync<TResponseData>(messageTag, new SignalPostJsonDataMessage<IdMessage>(new IdMessage(parameter)), GetNextRequestId());
+            => SendMessageToServerAsync<TResponseData>(messageTag, [parameter], GetNextRequestId());
 
         public virtual Task<TResponseData?> PostAsync<TResponseData>(int messageTag, object[] parameters)
-            => SendMessageToServerAsync<TResponseData>(messageTag, new SignalPostJsonDataMessage<IdMessage>(new IdMessage(parameters)), GetNextRequestId());
+            => SendMessageToServerAsync<TResponseData>(messageTag, parameters, GetNextRequestId());
 
         public virtual Task<TResponseData?> GetByIdAsync<TResponseData>(int messageTag, object id)
             => PostAsync<TResponseData?>(messageTag, id);
@@ -172,19 +172,19 @@ namespace AyCode.Services.SignalRs
         /// Gets data by ID with async callback response. Callback is second parameter.
         /// </summary>
         public virtual Task GetByIdAsync<TResponseData>(int messageTag, Func<SignalResponseDataMessage, Task> responseCallback, object id)
-            => SendMessageToServerAsync(messageTag, new SignalPostJsonDataMessage<IdMessage>(new IdMessage(id)), responseCallback);
+            => SendMessageToServerAsync(messageTag, [id], responseCallback);
 
         /// <summary>
         /// Gets data by IDs with async callback response. Callback is second parameter.
         /// </summary>
         public virtual Task GetByIdAsync<TResponseData>(int messageTag, Func<SignalResponseDataMessage, Task> responseCallback, object[] ids)
-            => SendMessageToServerAsync(messageTag, new SignalPostJsonDataMessage<IdMessage>(new IdMessage(ids)), responseCallback);
+            => SendMessageToServerAsync(messageTag, ids, responseCallback);
 
         public virtual Task<TResponseData?> GetAllAsync<TResponseData>(int messageTag)
             => SendMessageToServerAsync<TResponseData>(messageTag);
 
         public virtual Task<TResponseData?> GetAllAsync<TResponseData>(int messageTag, object[]? contextParams)
-            => SendMessageToServerAsync<TResponseData>(messageTag, contextParams == null || contextParams.Length == 0 ? null : new SignalPostJsonDataMessage<IdMessage>(new IdMessage(contextParams)), GetNextRequestId());
+            => SendMessageToServerAsync<TResponseData>(messageTag, contextParams is { Length: > 0 } ? contextParams : null, GetNextRequestId());
 
         /// <summary>
         /// Gets all data with async callback response. Callback is second parameter.
@@ -196,7 +196,7 @@ namespace AyCode.Services.SignalRs
         /// Gets all data with context params and async callback response.
         /// </summary>
         public virtual Task GetAllAsync<TResponseData>(int messageTag, Func<SignalResponseDataMessage, Task> responseCallback, object[]? contextParams)
-            => SendMessageToServerAsync(messageTag, contextParams == null || contextParams.Length == 0 ? null : new SignalPostJsonDataMessage<IdMessage>(new IdMessage(contextParams)), responseCallback);
+            => SendMessageToServerAsync(messageTag, contextParams is { Length: > 0 } ? contextParams : null, responseCallback);
 
         public virtual async IAsyncEnumerable<TResponseData?> StreamAllAsync<TResponseData>(int messageTag, object[]? contextParams = null, [System.Runtime.CompilerServices.EnumeratorCancellation] CancellationToken cancellationToken = default)
         {
@@ -208,8 +208,7 @@ namespace AyCode.Services.SignalRs
                 yield break;
             }
 
-            var message = contextParams == null || contextParams.Length == 0 ? null : new SignalPostJsonDataMessage<IdMessage>(new IdMessage(contextParams));
-            var msgBytes = message != null ? SignalRSerializationHelper.SerializeToBinary(message) : null;
+            var msgBytes = contextParams is { Length: > 0 } ? SignalRSerializationHelper.SerializeParametersToBinary(contextParams) : null;
 
             var stream = HubConnection.StreamAsync<byte[]>(
                 "OnReceiveStreamMessage", 
@@ -242,22 +241,22 @@ namespace AyCode.Services.SignalRs
         }
 
         public virtual Task<TPostData?> PostDataAsync<TPostData>(int messageTag, TPostData postData) where TPostData : class
-            => SendMessageToServerAsync<TPostData>(messageTag, CreatePostMessage(postData), GetNextRequestId());
+            => SendMessageToServerAsync<TPostData>(messageTag, [postData!], GetNextRequestId());
 
         public virtual Task<TResponseData?> PostDataAsync<TPostData, TResponseData>(int messageTag, TPostData postData)
-            => SendMessageToServerAsync<TResponseData>(messageTag, CreatePostMessage(postData), GetNextRequestId());
+            => SendMessageToServerAsync<TResponseData>(messageTag, [postData!], GetNextRequestId());
 
         /// <summary>
         /// Posts data with async callback response.
         /// </summary>
         public virtual Task PostDataAsync<TPostData>(int messageTag, TPostData postData, Func<SignalResponseDataMessage, Task> responseCallback)
-            => SendMessageToServerAsync(messageTag, CreatePostMessage(postData), responseCallback);
+            => SendMessageToServerAsync(messageTag, [postData!], responseCallback);
 
         /// <summary>
         /// Posts data with typed async callback response.
         /// </summary>
         public virtual Task PostDataAsync<TPostData, TResponseData>(int messageTag, TPostData postData, Func<SignalResponseDataMessage, Task> responseCallback)
-            => SendMessageToServerAsync(messageTag, CreatePostMessage(postData), responseCallback);
+            => SendMessageToServerAsync(messageTag, [postData!], responseCallback);
 
         /// <summary>
         /// Posts data and invokes callback with response. Fire-and-forget friendly for background saves.
@@ -268,7 +267,7 @@ namespace AyCode.Services.SignalRs
             var requestModel = SignalRRequestModelPool.Get(responseCallback);
 
             _responseByRequestId[requestId] = requestModel;
-            return SendMessageToServerAsync(messageTag, CreatePostMessage(postData), requestId);
+            return SendMessageToServerAsync(messageTag, [postData!], requestId);
         }
 
         public virtual async IAsyncEnumerable<TResponseData?> StreamPostDataAsync<TPostData, TResponseData>(int messageTag, TPostData postData, [System.Runtime.CompilerServices.EnumeratorCancellation] CancellationToken cancellationToken = default)
@@ -281,8 +280,7 @@ namespace AyCode.Services.SignalRs
                 yield break;
             }
 
-            var message = CreatePostMessage(postData);
-            var msgBytes = SignalRSerializationHelper.SerializeToBinary(message);
+            var msgBytes = SignalRSerializationHelper.SerializeParametersToBinary(new object[] { postData! });
 
             var stream = HubConnection.StreamAsync<byte[]>(
                 "OnReceiveStreamMessage", 
@@ -314,14 +312,6 @@ namespace AyCode.Services.SignalRs
             }
         }
 
-        private static ISignalRMessage CreatePostMessage<TPostData>(TPostData postData)
-        {
-            var type = typeof(TPostData);
-            if (type == typeof(string) || type.IsEnum || type.IsValueType)
-                return new SignalPostJsonDataMessage<IdMessage>(new IdMessage(postData!));
-            return new SignalPostJsonDataMessage<TPostData>(postData);
-        }
-
         public Task GetAllIntoAsync<TResponseItem>(List<TResponseItem> intoList, int messageTag, object[]? contextParams = null, Action? callback = null) where TResponseItem : IEntityGuid
         {
             return GetAllAsync<List<TResponseItem>>(messageTag, contextParams).ContinueWith(task =>
@@ -341,24 +331,24 @@ namespace AyCode.Services.SignalRs
         #endregion
 
         public virtual Task<TResponse?> SendMessageToServerAsync<TResponse>(int messageTag)
-            => SendMessageToServerAsync<TResponse>(messageTag, null, GetNextRequestId());
+            => SendMessageToServerAsync<TResponse>(messageTag, (object[]?)null, GetNextRequestId());
 
-        public virtual Task<TResponse?> SendMessageToServerAsync<TResponse>(int messageTag, ISignalRMessage? message)
-            => SendMessageToServerAsync<TResponse>(messageTag, message, GetNextRequestId());
+        public virtual Task<TResponse?> SendMessageToServerAsync<TResponse>(int messageTag, object[]? parameters)
+            => SendMessageToServerAsync<TResponse>(messageTag, parameters, GetNextRequestId());
 
         /// <summary>
         /// Sends message to server with async callback response.
         /// </summary>
-        public virtual async Task SendMessageToServerAsync(int messageTag, ISignalRMessage? message, Func<SignalResponseDataMessage, Task> responseCallback)
+        public virtual async Task SendMessageToServerAsync(int messageTag, object[]? parameters, Func<SignalResponseDataMessage, Task> responseCallback)
         {
             var requestId = GetNextRequestId();
             var requestModel = SignalRRequestModelPool.Get(responseCallback);
 
             _responseByRequestId[requestId] = requestModel;
-            await SendMessageToServerAsync(messageTag, message, requestId);
+            await SendMessageToServerAsync(messageTag, parameters, requestId);
         }
 
-        protected virtual async Task<TResponse?> SendMessageToServerAsync<TResponse>(int messageTag, ISignalRMessage? message, int requestId)
+        protected virtual async Task<TResponse?> SendMessageToServerAsync<TResponse>(int messageTag, object[]? parameters, int requestId)
         {
             Logger.DebugConditional($"Client SendMessageToServerAsync<TResult>; {nameof(requestId)}: {requestId}; {ConstHelper.NameByValue(TagsName, messageTag)}");
 
@@ -366,7 +356,7 @@ namespace AyCode.Services.SignalRs
             var requestModel = SignalRRequestModelPool.Get();
 
             _responseByRequestId[requestId] = requestModel;
-            await SendMessageToServerAsync(messageTag, message, requestId);
+            await SendMessageToServerAsync(messageTag, parameters, requestId);
 
             try
             {
@@ -441,7 +431,7 @@ namespace AyCode.Services.SignalRs
                     var responseMessage = new SignalResponseDataMessage
                     {
                         Status = receiveParams.Status,
-                        DataSerializerType = AcSerializerType.Binary,
+                        DataSerializerType = receiveParams.DataSerializerType,
                         ResponseData = data
                     };
 
diff --git a/AyCode.Services/SignalRs/IAcSignalRHubClient.cs b/AyCode.Services/SignalRs/IAcSignalRHubClient.cs
index bd84283..97560a8 100644
--- a/AyCode.Services/SignalRs/IAcSignalRHubClient.cs
+++ b/AyCode.Services/SignalRs/IAcSignalRHubClient.cs
@@ -13,6 +13,7 @@ namespace AyCode.Services.SignalRs;
 /// Message container for serialized parameter IDs.
 /// Optimized for common primitive types to avoid full JSON overhead.
 /// </summary>
+[Obsolete("Use direct object[] binary serialization instead of IdMessage JSON wrapper.")]
 public class IdMessage
 {
     public List<string> Ids { get; private set; }
@@ -61,6 +62,7 @@ public class IdMessage
 /// <summary>
 /// Message containing JSON-serialized post data.
 /// </summary>
+[Obsolete("Use direct object[] binary serialization instead of JSON-in-Binary wrapper.")]
 public class SignalPostJsonMessage
 {
     public string PostDataJson { get; set; } = "";
@@ -72,6 +74,7 @@ public class SignalPostJsonMessage
 /// <summary>
 /// Generic message containing JSON-serialized post data with typed access.
 /// </summary>
+[Obsolete("Use direct object[] binary serialization instead of JSON-in-Binary wrapper.")]
 public class SignalPostJsonDataMessage<TPostDataType> : SignalPostJsonMessage, ISignalPostMessage<TPostDataType>
 {
     [JsonIgnore]
@@ -98,11 +101,13 @@ public class SignalPostJsonDataMessage<TPostDataType> : SignalPostJsonMessage, I
 /// <summary>
 /// Simple message containing post data.
 /// </summary>
+[Obsolete("Use direct object[] binary serialization instead of message wrappers.")]
 public class SignalPostMessage<TPostData>(TPostData postData) : ISignalPostMessage<TPostData>
 {
     public TPostData? PostData { get; set; } = postData;
 }
 
+[Obsolete("Use direct object[] binary serialization instead of message wrappers.")]
 public interface ISignalPostMessage<TPostData> : ISignalRMessage
 {
     TPostData? PostData { get; }
@@ -436,5 +441,5 @@ public sealed class SignalResponseDataMessage : ISignalResponseMessage, IDisposa
 
 public interface IAcSignalRHubClient : IAcSignalRHubBase
 {
-    Task SendMessageToServerAsync(int messageTag, ISignalRMessage? message, int? requestId);
+    Task SendMessageToServerAsync(int messageTag, object[]? parameters, int? requestId);
 }
\ No newline at end of file
diff --git a/AyCode.Services/SignalRs/ISignalParams.cs b/AyCode.Services/SignalRs/ISignalParams.cs
index 7379270..ad3793f 100644
--- a/AyCode.Services/SignalRs/ISignalParams.cs
+++ b/AyCode.Services/SignalRs/ISignalParams.cs
@@ -1,3 +1,4 @@
+using AyCode.Core.Serializers;
 using AyCode.Core.Serializers.Attributes;
 
 namespace AyCode.Services.SignalRs;
@@ -16,4 +17,5 @@ public interface ISignalParams { }
 public class SignalReceiveParams : ISignalParams
 {
     public SignalResponseStatus Status { get; set; }
+    public AcSerializerType DataSerializerType { get; set; }
 }
diff --git a/AyCode.Services/SignalRs/SignalRSerializationHelper.cs b/AyCode.Services/SignalRs/SignalRSerializationHelper.cs
index 5c1bd45..a177572 100644
--- a/AyCode.Services/SignalRs/SignalRSerializationHelper.cs
+++ b/AyCode.Services/SignalRs/SignalRSerializationHelper.cs
@@ -24,6 +24,7 @@ public static class SignalRSerializationHelper
     /// Serialize a primitive value to JSON string with minimal overhead.
     /// Falls back to full JSON serialization for complex types.
     /// </summary>
+    [Obsolete("Use direct object[] binary serialization instead of JSON-encoded primitives.")]
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public static string SerializePrimitiveToJson(object value)
     {
@@ -42,6 +43,7 @@ public static class SignalRSerializationHelper
     /// <summary>
     /// Serialize a Guid to JSON string with pre-allocated buffer.
     /// </summary>
+    [Obsolete("Use direct object[] binary serialization instead of JSON-encoded Guids.")]
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public static string SerializeGuidToJson(Guid g)
     {
@@ -96,6 +98,103 @@ public static class SignalRSerializationHelper
         return data.BinaryTo<T>();
     }
 
+    /// <summary>
+    /// Serialize method parameters as individually length-prefixed binary segments.
+    /// Format: [VarUInt count] [for each: INT32 length + AcBinary bytes]
+    /// This allows the server to deserialize each parameter with its known target type.
+    /// </summary>
+    public static byte[] SerializeParametersToBinary(object[] parameters, AcBinarySerializerOptions? options = null)
+    {
+        var opts = options ?? AcBinarySerializerOptions.Default;
+        var writer = new ArrayBufferWriter<byte>(256);
+
+        // Write parameter count as VarUInt
+        WriteVarUInt(writer, (uint)parameters.Length);
+
+        // Write each parameter with INT32 length prefix
+        for (var i = 0; i < parameters.Length; i++)
+        {
+            var paramWriter = new ArrayBufferWriter<byte>(128);
+            parameters[i].ToBinary(paramWriter, opts);
+
+            // Write length prefix
+            var lenSpan = writer.GetSpan(4);
+            System.Runtime.CompilerServices.Unsafe.WriteUnaligned(ref lenSpan[0], paramWriter.WrittenCount);
+            writer.Advance(4);
+
+            // Write parameter bytes
+            var paramSpan = writer.GetSpan(paramWriter.WrittenCount);
+            paramWriter.WrittenSpan.CopyTo(paramSpan);
+            writer.Advance(paramWriter.WrittenCount);
+        }
+
+        return writer.WrittenSpan.ToArray();
+    }
+
+    /// <summary>
+    /// Deserialize method parameters from length-prefixed binary format, using target types.
+    /// </summary>
+    public static object?[] DeserializeParametersFromBinary(byte[] data, System.Reflection.ParameterInfo[] paramInfos)
+    {
+        var span = data.AsSpan();
+        var pos = 0;
+
+        // Read parameter count
+        var count = (int)ReadVarUInt(span, ref pos);
+        var result = new object?[paramInfos.Length];
+
+        for (var i = 0; i < count && i < paramInfos.Length; i++)
+        {
+            // Read length prefix
+            var len = System.Runtime.CompilerServices.Unsafe.ReadUnaligned<int>(ref System.Runtime.InteropServices.MemoryMarshal.GetReference(span.Slice(pos)));
+            pos += 4;
+
+            if (len > 0)
+            {
+                var paramBytes = span.Slice(pos, len).ToArray();
+                result[i] = paramBytes.BinaryTo(paramInfos[i].ParameterType);
+                pos += len;
+            }
+        }
+
+        // Fill remaining with defaults
+        for (var i = count; i < paramInfos.Length; i++)
+        {
+            if (paramInfos[i].HasDefaultValue)
+                result[i] = paramInfos[i].DefaultValue;
+        }
+
+        return result;
+    }
+
+    private static void WriteVarUInt(ArrayBufferWriter<byte> writer, uint value)
+    {
+        while (value >= 0x80)
+        {
+            var span = writer.GetSpan(1);
+            span[0] = (byte)(value | 0x80);
+            writer.Advance(1);
+            value >>= 7;
+        }
+        var lastSpan = writer.GetSpan(1);
+        lastSpan[0] = (byte)value;
+        writer.Advance(1);
+    }
+
+    private static uint ReadVarUInt(ReadOnlySpan<byte> span, ref int pos)
+    {
+        uint value = 0;
+        var shift = 0;
+        while (true)
+        {
+            var b = span[pos++];
+            value |= (uint)(b & 0x7F) << shift;
+            if ((b & 0x80) == 0)
+                return value;
+            shift += 7;
+        }
+    }
+
     #endregion
 
     #region JSON Serialization with Brotli
diff --git a/AyCode.Services/docs/SIGNALR.md b/AyCode.Services/docs/SIGNALR.md
index 5e4775d..367df60 100644
--- a/AyCode.Services/docs/SIGNALR.md
+++ b/AyCode.Services/docs/SIGNALR.md
@@ -58,9 +58,10 @@ public abstract class MyProjectTags : AcSignalRTags
 
 **Usage:**
 ```csharp
-var orders = await client.PostAsync<List<Order>>(MyTags.GetOrders, companyId);
+var orders = await client.PostAsync<List<Order>>(MyTags.GetOrders, companyId);        // single param
+var result = await client.PostAsync<T>(MyTags.Query, [companyId, filter]);            // object[] params
 await client.PostDataAsync(MyTags.SaveOrder, order);
-await client.PostDataAsync(MyTags.SaveOrder, order, async response => { ... }); // async callback
+await client.PostDataAsync(MyTags.SaveOrder, order, async response => { ... });       // async callback
 ```
 
 CRUD helpers (`PostAsync`, `GetByIdAsync`, `GetAllAsync`, `PostDataAsync`) are generic transport, not tied to DataSource.
@@ -80,26 +81,24 @@ Custom `IHubProtocol` (`"acbinary"`), replaces JSON. Zero-copy via `BufferWriter
 | Field | Type | Purpose |
 |-------|------|---------|
 | `Status` | SignalResponseStatus | Success/Error |
+| `DataSerializerType` | AcSerializerType | Binary or JsonGZip — tells client how to deserialize response data |
 
 `byte[] data` (separate hub argument, protocol fast-path, zero-copy).
 
-`SignalResponseDataMessage` remains as **internal DTO** for callback routing — constructed in-memory from `receiveParams` + `data`, never serialized as envelope on wire.
-
-Binary (default): `AcBinarySerializer.ToBinary(data)`. JSON fallback: `ToJson` → `GzipHelper.Compress`.
+`SignalResponseDataMessage` remains as **internal DTO** for callback routing — constructed in-memory from `receiveParams` + `data`, never serialized as envelope on wire. `GetResponseData<T>()` dispatches on `DataSerializerType`: Binary → `BinaryTo<T>()`, JsonGZip → decompress → `JsonTo<T>()`.
 
 ## Request/Response Flow
 
 ### Client → Server
 
 ```
-1. PostAsync<T>(tag, postData) / PostDataAsync(tag, data, callback)
-2. CreatePostMessage(postData):
-   ├─ Primitives/strings/enums/value types → IdMessage
-   └─ Complex → SignalPostJsonDataMessage<T>   ⚠️ JSON-in-Binary tech debt
-3. SerializeToBinary(message)
-4. SignalReceiveParams { Status = Success }
-5. HubConnection.SendAsync("OnReceiveMessage", tag, requestId, receiveParams, bytes)
-6. AcBinaryHubProtocol frames on wire (byte[] via fast-path, receiveParams via AcBinary)
+1. PostAsync<T>(tag, param) / PostAsync<T>(tag, params[]) / PostDataAsync(tag, data, callback)
+2. SerializeParametersToBinary(object[] parameters):
+   [VarUInt count] [for each: INT32 length + AcBinary bytes]
+   Each parameter individually binary-serialized with length prefix.
+3. SignalReceiveParams { Status = Success }
+4. HubConnection.SendAsync("OnReceiveMessage", tag, requestId, receiveParams, bytes)
+5. AcBinaryHubProtocol frames on wire (byte[] via fast-path, receiveParams via AcBinary)
 ```
 
 ### Server → Client
@@ -107,10 +106,11 @@ Binary (default): `AcBinarySerializer.ToBinary(data)`. JSON fallback: `ToJson` 
 ```
 OnReceiveMessage(tag, requestId, receiveParams, data)
 ├─ Construct SignalResponseDataMessage in-memory (no envelope deser):
-│  └─ { Status = receiveParams.Status, DataSerializerType = Binary, ResponseData = data }
+│  └─ { Status, DataSerializerType, ResponseData } from receiveParams + data
 ├─ Matching requestId in pending dict:
 │  ├─ Route: null→sync wait, Action→invoke, Func<Task>→await
-│  └─ GetResponseData<T>(): Binary→BinaryTo<T>(), JSON→Decompress→Deserialize
+│  └─ GetResponseData<T>(): dispatches on DataSerializerType
+│     Binary→BinaryTo<T>(), JsonGZip→Decompress→JsonTo<T>()
 └─ No match (broadcast):
    └─ abstract MessageReceived(tag, receiveParams, data).Forget()
 ```
@@ -136,9 +136,20 @@ Request pooling: `SignalRRequestModel` via `SignalRRequestModelPool` (ObjectPool
 
 `AcSignalRClientBase.EnableBinaryDiagnostics = true` — hex dump, header parsing, property enumeration.
 
-## Tech Debt
+## Parameter Serialization
 
-**JSON-in-Binary:** client→server wraps params in JSON inside binary envelope (`SignalPostJsonDataMessage`). Do NOT fix as side effect — requires coordinated cross-project changes.
+Client→server parameters use length-prefixed per-parameter binary format via `SignalRSerializationHelper`:
+
+```
+SerializeParametersToBinary(object[]):
+  [VarUInt count] [for each: INT32 length + AcBinary bytes]
+
+DeserializeParametersFromBinary(byte[], ParameterInfo[]):
+  Server reads each segment and deserializes with known target type from method signature.
+  Trailing parameters with defaults are auto-filled.
+```
+
+This enables type-guided deserialization — each parameter is individually serialized/deserialized with its concrete type, avoiding the `object[]` → dictionary problem of untyped binary deserialization.
 
 ## Source Files
 
diff --git a/docs/GLOSSARY.md b/docs/GLOSSARY.md
index 492fbeb..0a991e2 100644
--- a/docs/GLOSSARY.md
+++ b/docs/GLOSSARY.md
@@ -70,14 +70,15 @@ For full architecture see `AyCode.Services/docs/SIGNALR.md`.
 
 | Term | Definition |
 |---|---|
-| **OnReceiveMessage** | The single SignalR method for all communication. Signature: `(int messageTag, int? requestId, SignalReceiveParams receiveParams, byte[] data)`. Metadata and payload are separate hub arguments — `byte[]` uses protocol zero-copy fast-path. |
-| **SignalReceiveParams** | Lightweight metadata sent alongside message payload as separate hub argument. Contains `Status` (SignalResponseStatus). Implements `ISignalParams`. AcBinary serialized. |
+| **OnReceiveMessage** | The single SignalR method for all communication. Signature: `(int messageTag, int? requestId, SignalReceiveParams receiveParams, byte[] data)`. Metadata and payload are separate hub arguments — `byte[]` uses protocol zero-copy fast-path. Client→server: `data` is length-prefixed parameter binary. Server→client: `data` is response payload (format indicated by `receiveParams.DataSerializerType`). |
+| **SignalReceiveParams** | Lightweight metadata sent alongside message payload as separate hub argument. Contains `Status` (SignalResponseStatus) and `DataSerializerType` (AcSerializerType — Binary or JsonGZip, tells client how to deserialize response data). Implements `ISignalParams`. AcBinary serialized. |
 | **Message Tag** | Integer identifier mapping to a method via `[SignalR(tag)]` or `[SignalRSendToClient(tag)]` attributes. |
 | **DynamicMethodRegistry** | Resolves message tags to `MethodInfo` at runtime. Static `ConcurrentDictionary` cache with lazy scan on miss. |
 | **SignalRCrudTags** | Sealed class bundling 5 independent tag integers (getAllTag, getItemTag, addTag, updateTag, removeTag) for entity CRUD. See `AyCode.Services.Server/docs/SIGNALR_DATASOURCE.md`. |
 | **AcBinaryHubProtocol** | Custom `IHubProtocol` replacing SignalR's JSON+Base64 with `AcBinarySerializer`. Protocol name: `"acbinary"`. Uses `BufferWriterBinaryOutput` for zero-copy writes to the SignalR pipe. |
 | **SignalResponseDataMessage** | Internal DTO for callback routing (not serialized on wire). Constructed in-memory from `receiveParams` + `data`. Supports Binary or JSON+GZip via `GetResponseData<T>()`. |
-| **SignalPostJsonDataMessage** | ⚠️ TECH DEBT — request params serialized to JSON inside Binary envelope. Planned for pure Binary replacement. |
+| **SignalPostJsonDataMessage** | ⚠️ OBSOLETE — replaced by `SerializeParametersToBinary(object[])`. Legacy: serialized params to JSON inside Binary envelope. |
+| **SerializeParametersToBinary** | Length-prefixed per-parameter binary format: `[VarUInt count][INT32 len + AcBinary bytes per param]`. Server deserializes each with target type from method signature via `DeserializeParametersFromBinary`. In `SignalRSerializationHelper`. |
 | **AcSignalRDataSource** | Generic real-time `IList<T>` with change tracking, CRUD via SignalRCrudTags, binary merge, rollback, sync state. |
 | **TrackingItem** | Wraps a modified DataSource item with `TrackingState` (Add/Update/Remove) + `OriginalValue` for rollback. |
 | **SendToClientType** | Enum controlling broadcast scope: None, Others, Caller, All. |