Lots of refactoring

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/AnimBlueprint_Create.h

@@ -2,7 +2,7 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
 #include "MCPPackageMaker.h"
 #include "Animation/AnimBlueprint.h"
@@ -39,14 +39,12 @@ public:
 
 	virtual void Handle(FStringBuilderBase& Result) override
 	{
-		MCPErrorCallback CB(Result);
-
-		MCPPackageMaker Maker(AssetPath, CB);
+		MCPPackageMaker Maker(AssetPath);
 		if (!Maker.Ok()) return;
 
 		// Resolve skeleton
 		MCPAssets<USkeleton> SkeletonAssets;
-		if (!SkeletonAssets.Exact(Skeleton).Errors(CB).ENone().ETwo().Load()) return;
+		if (!SkeletonAssets.Exact(Skeleton).ENone().ETwo().Load()) return;
 		USkeleton* SkeletonObj = SkeletonAssets.Object();
 
 		// Resolve parent class (default: UAnimInstance)
@@ -64,7 +62,8 @@ public:
 			}
 			if (!Found)
 			{
-				return CB.SetError(FString::Printf(TEXT("Parent class '%s' not found (must derive from AnimInstance)"), *ParentClass));
+				UMCPServer::Printf(TEXT("ERROR: Parent class '%s' not found (must derive from AnimInstance)\n"), *ParentClass);
+				return;
 			}
 			ParentClassObj = Found;
 		}
@@ -84,7 +83,8 @@ public:
 
 		if (!NewAnimBP)
 		{
-			return CB.SetError(TEXT("FKismetEditorUtilities::CreateBlueprint returned null"));
+			UMCPServer::Print(TEXT("ERROR: FKismetEditorUtilities::CreateBlueprint returned null\n"));
+			return;
 		}
 
 		// Set target skeleton

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/AnimBlueprint_ListSlotNames.h

@@ -2,7 +2,7 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
 #include "Animation/AnimBlueprint.h"
 #include "AnimGraphNode_Base.h"
@@ -30,7 +30,7 @@ public:
 	virtual void Handle(FStringBuilderBase& Result) override
 	{
 		MCPAssets<UAnimBlueprint> Assets;
-		if (!Assets.Exact(Blueprint).Errors(Result).ENone().ETwo().Load()) return;
+		if (!Assets.Exact(Blueprint).ENone().ETwo().Load()) return;
 		UAnimBlueprint* AnimBP = Assets.Object();
 
 		// Walk all anim nodes to collect slot names

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/AnimBlueprint_SetBlendSpaceSamples.h

@@ -2,7 +2,7 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
 #include "Animation/AnimSequence.h"
@@ -69,7 +69,7 @@ public:
 	{
 		// Load the blend space
 		MCPAssets<UBlendSpace> Assets;
-		if (!Assets.Exact(BlendSpace).Errors(Result).ENone().ETwo().Load()) return;
+		if (!Assets.Exact(BlendSpace).ENone().ETwo().Load()) return;
 		UBlendSpace* BS = Assets.Object();
 
 		// Set axis parameters
@@ -101,13 +101,13 @@ public:
 		for (const TSharedPtr<FJsonValue>& SampleVal : Samples.Array)
 		{
 			FBlendSpaceSampleEntry Entry;
-			if (!MCPUtils::PopulateFromJson(FBlendSpaceSampleEntry::StaticStruct(), &Entry, SampleVal, Result)) return;
+			if (!MCPUtils::PopulateFromJson(FBlendSpaceSampleEntry::StaticStruct(), &Entry, SampleVal)) return;
 
 			UAnimSequence* AnimSeq = nullptr;
 			if (!Entry.AnimationAsset.IsEmpty())
 			{
 				MCPAssets<UAnimSequence> AnimAssets;
-				if (!AnimAssets.Exact(Entry.AnimationAsset).Errors(Result).ENone().Load()) return;
+				if (!AnimAssets.Exact(Entry.AnimationAsset).ENone().Load()) return;
 				AnimSeq = AnimAssets.Object();
 			}
 

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Asset_Delete.h

@@ -2,7 +2,7 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
 #include "Misc/PackageName.h"
 #include "AssetRegistry/AssetRegistryModule.h"

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Asset_Rename.h

@@ -2,7 +2,7 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
 #include "AssetToolsModule.h"
 #include "IAssetTools.h"
@@ -34,7 +34,7 @@ public:
 	{
 		// Load the asset
 		MCPAssets<UObject> Assets;
-		if (!Assets.Exact(AssetPath).AllContent().Errors(Result).ENone().ETwo().Load()) return;
+		if (!Assets.Exact(AssetPath).AllContent().ENone().ETwo().Load()) return;
 		UObject* AssetObj = Assets.Object();
 
 		// Parse new path into package path and asset name

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Asset_Search.h

@@ -2,7 +2,7 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
 #include "Asset_Search.generated.h"
 
@@ -58,7 +58,7 @@ public:
 			Assets.Substring(Query);
 		}
 
-		Assets.AllContent().Limit(Limit).Errors(Result).Info();
+		Assets.AllContent().Limit(Limit).Info();
 
 		const TArray<FAssetData>& AllData = Assets.AllData();
 		for (const FAssetData& Data : AllData)

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/BlendSpace_Create.h

@@ -2,7 +2,7 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
 #include "MCPPackageMaker.h"
 #include "Animation/Skeleton.h"
@@ -33,14 +33,12 @@ public:
 
 	virtual void Handle(FStringBuilderBase& Result) override
 	{
-		MCPErrorCallback CB(Result);
-
-		MCPPackageMaker Maker(AssetPath, CB);
+		MCPPackageMaker Maker(AssetPath);
 		if (!Maker.Ok()) return;
 
 		// Resolve skeleton.
 		MCPAssets<USkeleton> SkeletonAssets;
-		if (!SkeletonAssets.Exact(Skeleton).Errors(CB).ENone().ETwo().Load()) return;
+		if (!SkeletonAssets.Exact(Skeleton).ENone().ETwo().Load()) return;
 		USkeleton* SkeletonObj = SkeletonAssets.Object();
 
 		// Create the package and Blend Space.

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Blueprint_AddComponent.h

@@ -2,8 +2,9 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
+#include "MCPServer.h"
 #include "Engine/Blueprint.h"
 #include "Engine/SimpleConstructionScript.h"
 #include "Engine/SCS_Node.h"
@@ -42,15 +43,14 @@ public:
 	virtual void Handle(FStringBuilderBase& Result) override
 	{
 		MCPAssets<UBlueprint> Assets;
-		if (!Assets.Exact(Blueprint).Errors(Result).ENone().ETwo().Load()) return;
+		if (!Assets.Exact(Blueprint).ENone().ETwo().Load()) return;
 		UBlueprint* BP = Assets.Object();
 
 		USimpleConstructionScript* SCS = BP->SimpleConstructionScript;
 		if (!SCS)
 		{
-			MCPErrorCallback(Result).SetError(FString::Printf(
-				TEXT("Blueprint '%s' does not have a SimpleConstructionScript (not an Actor Blueprint)"),
-				*MCPUtils::FormatName(BP)));
+			UMCPServer::Printf(TEXT("ERROR: Blueprint '%s' does not have a SimpleConstructionScript (not an Actor Blueprint)\n"),
+				*MCPUtils::FormatName(BP));
 			return;
 		}
 
@@ -61,9 +61,8 @@ public:
 			if (Existing && Existing->ComponentTemplate &&
 				MCPUtils::Identifies(Component, Existing->ComponentTemplate))
 			{
-				MCPErrorCallback(Result).SetError(FString::Printf(
-					TEXT("A component named '%s' already exists in Blueprint '%s'"),
-					*Component, *MCPUtils::FormatName(BP)));
+				UMCPServer::Printf(TEXT("ERROR: A component named '%s' already exists in Blueprint '%s'\n"),
+					*Component, *MCPUtils::FormatName(BP));
 				return;
 			}
 		}
@@ -72,13 +71,12 @@ public:
 		UClass* ComponentClassObj = MCPUtils::FindClassByName(ComponentClass);
 		if (!ComponentClassObj || !ComponentClassObj->IsChildOf(UActorComponent::StaticClass()))
 		{
-			MCPErrorCallback(Result).SetError(FString::Printf(
-				TEXT("Component class '%s' not found or is not a subclass of UActorComponent. "
-					"Common classes: StaticMeshComponent, SkeletalMeshComponent, AudioComponent, "
-					"SceneComponent, BoxCollisionComponent, SphereCollisionComponent, CapsuleComponent, "
-					"ArrowComponent, ChildActorComponent, SpotLightComponent, PointLightComponent, "
-					"WidgetComponent, BillboardComponent"),
-				*ComponentClass));
+			UMCPServer::Printf(TEXT("ERROR: Component class '%s' not found or is not a subclass of UActorComponent. "
+				"Common classes: StaticMeshComponent, SkeletalMeshComponent, AudioComponent, "
+				"SceneComponent, BoxCollisionComponent, SphereCollisionComponent, CapsuleComponent, "
+				"ArrowComponent, ChildActorComponent, SpotLightComponent, PointLightComponent, "
+				"WidgetComponent, BillboardComponent\n"),
+				*ComponentClass);
 			return;
 		}
 
@@ -98,9 +96,8 @@ public:
 
 			if (!ParentSCSNode)
 			{
-				MCPErrorCallback(Result).SetError(FString::Printf(
-					TEXT("Parent component '%s' not found in Blueprint '%s'"),
-					*ParentComponent, *MCPUtils::FormatName(BP)));
+				UMCPServer::Printf(TEXT("ERROR: Parent component '%s' not found in Blueprint '%s'\n"),
+					*ParentComponent, *MCPUtils::FormatName(BP));
 				return;
 			}
 		}
@@ -109,9 +106,8 @@ public:
 		USCS_Node* NewNode = SCS->CreateNode(ComponentClassObj, FName(*Component));
 		if (!NewNode)
 		{
-			MCPErrorCallback(Result).SetError(FString::Printf(
-				TEXT("Failed to create SCS node for component '%s' with class '%s'"),
-				*Component, *MCPUtils::FormatName(ComponentClassObj)));
+		UMCPServer::Printf(TEXT("ERROR: Failed to create SCS node for component '%s' with class '%s'\n"),
+				*Component, *MCPUtils::FormatName(ComponentClassObj));
 			return;
 		}
 

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Blueprint_AddEventDispatcher.h

@@ -123,11 +123,11 @@ public:
 			for (const TSharedPtr<FJsonValue>& ParamVal : Parameters.Array)
 			{
 				FDispatcherParamEntry Entry;
-				if (!MCPUtils::PopulateFromJson(FDispatcherParamEntry::StaticStruct(), &Entry, ParamVal, Result)) return;
+				if (!MCPUtils::PopulateFromJson(FDispatcherParamEntry::StaticStruct(), &Entry, ParamVal)) return;
 				if (Entry.Name.IsEmpty() || Entry.Type.IsEmpty()) continue;
 
 				FEdGraphPinType PinType;
-				if (!MCPUtils::ResolveTypeFromString(Entry.Type, PinType, Result))
+				if (!MCPUtils::ResolveTypeFromString(Entry.Type, PinType))
 					return;
 
 				EntryNode->CreateUserDefinedPin(FName(*Entry.Name), PinType, EGPD_Output);

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Blueprint_AddFunctionParameter.h

@@ -2,8 +2,9 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
+#include "MCPServer.h"
 #include "Engine/Blueprint.h"
 #include "EdGraph/EdGraph.h"
 #include "EdGraph/EdGraphPin.h"
@@ -44,12 +45,12 @@ public:
 	virtual void Handle(FStringBuilderBase& Result) override
 	{
 		MCPAssets<UBlueprint> Assets;
-		if (!Assets.Exact(Blueprint).Errors(Result).ENone().ETwo().Load()) return;
+		if (!Assets.Exact(Blueprint).ENone().ETwo().Load()) return;
 		UBlueprint* BP = Assets.Object();
 
 		// Resolve param type
 		FEdGraphPinType PinType;
-		if (!MCPUtils::ResolveTypeFromString(ParamType, PinType, Result))
+		if (!MCPUtils::ResolveTypeFromString(ParamType, PinType))
 			return;
 
 		// Find the entry node using 3 strategies
@@ -101,22 +102,21 @@ public:
 		if (!EntryNode)
 		{
 			// Build a helpful error listing available functions, events, and dispatchers
-			MCPErrorCallback(Result).SetError(FString::Printf(
-				TEXT("Function/event/dispatcher '%s' not found. Available:\n"), *FunctionName));
+			UMCPServer::Printf(TEXT("ERROR: Function/event/dispatcher '%s' not found. Available:\n"), *FunctionName);
 
 			for (UEdGraph* Graph : BP->FunctionGraphs)
 			{
-				if (Graph) Result.Appendf(TEXT("  function: %s\n"), *MCPUtils::FormatName(Graph));
+				if (Graph) UMCPServer::Printf(TEXT("  function: %s\n"), *MCPUtils::FormatName(Graph));
 			}
 			for (UK2Node_CustomEvent* CE : MCPUtils::AllNodes<UK2Node_CustomEvent>(BP))
 			{
-				Result.Appendf(TEXT("  custom event: %s\n"), *CE->CustomFunctionName.ToString());
+				UMCPServer::Printf(TEXT("  custom event: %s\n"), *CE->CustomFunctionName.ToString());
 			}
 			TSet<FName> DelegateNames;
 			FBlueprintEditorUtils::GetDelegateNameList(BP, DelegateNames);
 			for (const FName& DN : DelegateNames)
 			{
-				Result.Appendf(TEXT("  dispatcher: %s\n"), *DN.ToString());
+				UMCPServer::Printf(TEXT("  dispatcher: %s\n"), *DN.ToString());
 			}
 			return;
 		}
@@ -126,8 +126,7 @@ public:
 		{
 			if (Existing.IsValid() && Existing->PinName.ToString().Equals(ParamName, ESearchCase::IgnoreCase))
 			{
-				MCPErrorCallback(Result).SetError(FString::Printf(
-					TEXT("Parameter '%s' already exists on '%s'"), *ParamName, *FunctionName));
+				UMCPServer::Printf(TEXT("ERROR: Parameter '%s' already exists on '%s'\n"), *ParamName, *FunctionName);
 				return;
 			}
 		}

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Blueprint_AddInterface.h

@@ -2,8 +2,9 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
+#include "MCPServer.h"
 #include "Engine/Blueprint.h"
 #include "Kismet2/BlueprintEditorUtils.h"
 #include "UObject/UObjectIterator.h"
@@ -35,7 +36,7 @@ public:
 	virtual void Handle(FStringBuilderBase& Result) override
 	{
 		MCPAssets<UBlueprint> Assets;
-		if (!Assets.Exact(Blueprint).Errors(Result).ENone().ETwo().Load()) return;
+		if (!Assets.Exact(Blueprint).ENone().ETwo().Load()) return;
 		UBlueprint* BP = Assets.Object();
 
 		// Resolve the interface class
@@ -47,9 +48,8 @@ public:
 		{
 			if (IfaceDesc.Interface == InterfaceClass)
 			{
-				MCPErrorCallback(Result).SetError(FString::Printf(
-					TEXT("Interface '%s' is already implemented by this Blueprint."),
-					*MCPUtils::FormatName(InterfaceClass)));
+				UMCPServer::Printf(TEXT("ERROR: Interface '%s' is already implemented by this Blueprint.\n"),
+					*MCPUtils::FormatName(InterfaceClass));
 				return;
 			}
 		}
@@ -58,9 +58,8 @@ public:
 		bool bAdded = FBlueprintEditorUtils::ImplementNewInterface(BP, InterfacePath);
 		if (!bAdded)
 		{
-			MCPErrorCallback(Result).SetError(FString::Printf(
-				TEXT("ImplementNewInterface failed for '%s'."),
-				*MCPUtils::FormatName(InterfaceClass)));
+			UMCPServer::Printf(TEXT("ERROR: ImplementNewInterface failed for '%s'.\n"),
+				*MCPUtils::FormatName(InterfaceClass));
 			return;
 		}
 
@@ -95,7 +94,7 @@ private:
 
 		// Strategy 2: Try loading as a Blueprint Interface asset
 		MCPAssets<UBlueprint> IfaceAssets;
-		if (!IfaceAssets.Exact(Name).AllContent().Errors(Result).ETwo().Load()) return nullptr;
+		if (!IfaceAssets.Exact(Name).AllContent().ETwo().Load()) return nullptr;
 		if (!IfaceAssets.Objects().IsEmpty())
 		{
 			UClass* GenClass = IfaceAssets.Object()->GeneratedClass;
@@ -103,9 +102,8 @@ private:
 				return GenClass;
 		}
 
-		MCPErrorCallback(Result).SetError(FString::Printf(
-			TEXT("Interface '%s' not found. Provide a Blueprint Interface asset name (e.g. 'BPI_MyInterface') or a native UInterface class name."),
-			*Name));
+		UMCPServer::Printf(TEXT("ERROR: Interface '%s' not found. Provide a Blueprint Interface asset name (e.g. 'BPI_MyInterface') or a native UInterface class name.\n"),
+			*Name);
 		return nullptr;
 	}
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Blueprint_AddVariable.h

@@ -2,8 +2,9 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
+#include "MCPServer.h"
 #include "Engine/Blueprint.h"
 #include "Kismet2/BlueprintEditorUtils.h"
 #include "Blueprint_AddVariable.generated.h"
@@ -45,7 +46,7 @@ public:
 	virtual void Handle(FStringBuilderBase& Result) override
 	{
 		MCPAssets<UBlueprint> Assets;
-		if (!Assets.Exact(Blueprint).Errors(Result).ENone().ETwo().Load()) return;
+		if (!Assets.Exact(Blueprint).ENone().ETwo().Load()) return;
 		UBlueprint* BP = Assets.Object();
 
 		// Check for duplicate variable name
@@ -54,15 +55,14 @@ public:
 		{
 			if (Var.VarName == VarFName)
 			{
-				MCPErrorCallback(Result).SetError(FString::Printf(
-					TEXT("Variable '%s' already exists in %s"), *VariableName, *MCPUtils::FormatName(BP)));
+				UMCPServer::Printf(TEXT("ERROR: Variable '%s' already exists in %s\n"), *VariableName, *MCPUtils::FormatName(BP));
 				return;
 			}
 		}
 
 		// Resolve the type
 		FEdGraphPinType PinType;
-		if (!MCPUtils::ResolveTypeFromString(VariableType, PinType, Result))
+		if (!MCPUtils::ResolveTypeFromString(VariableType, PinType))
 			return;
 
 		if (IsArray)
@@ -71,8 +71,7 @@ public:
 		// Add the variable
 		if (!FBlueprintEditorUtils::AddMemberVariable(BP, VarFName, PinType, DefaultValue))
 		{
-			MCPErrorCallback(Result).SetError(FString::Printf(
-				TEXT("Failed to add variable '%s' to %s"), *VariableName, *MCPUtils::FormatName(BP)));
+			UMCPServer::Printf(TEXT("ERROR: Failed to add variable '%s' to %s\n"), *VariableName, *MCPUtils::FormatName(BP));
 			return;
 		}
 

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Blueprint_ChangeFunctionParameterType.h

@@ -2,8 +2,9 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
+#include "MCPServer.h"
 #include "Engine/Blueprint.h"
 #include "EdGraph/EdGraph.h"
 #include "EdGraph/EdGraphPin.h"
@@ -47,12 +48,12 @@ public:
 	virtual void Handle(FStringBuilderBase& Result) override
 	{
 		MCPAssets<UBlueprint> Assets;
-		if (!Assets.Exact(Blueprint).Errors(Result).ENone().ETwo().Load()) return;
+		if (!Assets.Exact(Blueprint).ENone().ETwo().Load()) return;
 		UBlueprint* BP = Assets.Object();
 
 		// Resolve the new type using the shared resolver (supports primitives, structs, enums, and object references)
 		FEdGraphPinType NewPinType;
-		if (!MCPUtils::ResolveTypeFromString(NewType, NewPinType, Result))
+		if (!MCPUtils::ResolveTypeFromString(NewType, NewPinType))
 			return;
 
 		// Find the entry node: K2Node_FunctionEntry in a function graph,
@@ -84,12 +85,11 @@ public:
 
 		if (!EntryNode)
 		{
-			MCPErrorCallback(Result).SetError(FString::Printf(
-				TEXT("Function or custom event '%s' not found. Available:"), *FunctionName));
+			UMCPServer::Printf(TEXT("ERROR: Function or custom event '%s' not found. Available:\n"), *FunctionName);
 			for (UK2Node_FunctionEntry* FE : MCPUtils::AllNodes<UK2Node_FunctionEntry>(BP))
-				Result.Appendf(TEXT("  function: %s\n"), *MCPUtils::FormatName(FE->GetGraph()));
+				UMCPServer::Printf(TEXT("  function: %s\n"), *MCPUtils::FormatName(FE->GetGraph()));
 			for (UK2Node_CustomEvent* CE : MCPUtils::AllNodes<UK2Node_CustomEvent>(BP))
-				Result.Appendf(TEXT("  event: %s\n"), *MCPUtils::FormatName(static_cast<UEdGraphNode*>(CE)));
+				UMCPServer::Printf(TEXT("  event: %s\n"), *MCPUtils::FormatName(static_cast<UEdGraphNode*>(CE)));
 			return;
 		}
 
@@ -106,11 +106,10 @@ public:
 
 		if (!FoundPinInfo)
 		{
-			MCPErrorCallback(Result).SetError(FString::Printf(
-				TEXT("Parameter '%s' not found. Available:"), *ParamName));
+			UMCPServer::Printf(TEXT("ERROR: Parameter '%s' not found. Available:\n"), *ParamName);
 			for (const TSharedPtr<FUserPinInfo>& PinInfo : EntryNode->UserDefinedPins)
 				if (PinInfo.IsValid())
-					Result.Appendf(TEXT("  %s\n"), *PinInfo->PinName.ToString());
+					UMCPServer::Printf(TEXT("  %s\n"), *PinInfo->PinName.ToString());
 			return;
 		}
 

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Blueprint_ChangeVariableType.h

@@ -3,7 +3,7 @@
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
 #include "Engine/Blueprint.h"
 #include "EdGraph/EdGraphPin.h"
@@ -81,7 +81,7 @@ public:
 			ResolveInput = TypeCategory + TEXT(":") + NewType;
 		}
 
-		if (!MCPUtils::ResolveTypeFromString(ResolveInput, NewPinType, Result))
+		if (!MCPUtils::ResolveTypeFromString(ResolveInput, NewPinType))
 			return;
 
 		// List affected nodes (get/set nodes for this variable)

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Blueprint_Compile.h

@@ -2,7 +2,7 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
 #include "Engine/Blueprint.h"
 #include "Kismet2/KismetEditorUtilities.h"
@@ -88,7 +88,7 @@ public:
 	virtual void Handle(FStringBuilderBase& Result) override
 	{
 		MCPAssets<UBlueprint> Finder;
-		Finder.Scan<UBlueprint>().Scan<UWorld>().Errors(Result);
+		Finder.Scan<UBlueprint>().Scan<UWorld>();
 		if (!Blueprint.IsEmpty())
 		{
 			if (!Finder.Exact(Blueprint).ENone().ETwo().Info()) return;

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Blueprint_Create.h

@@ -2,7 +2,7 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
 #include "MCPPackageMaker.h"
 #include "Engine/Blueprint.h"
@@ -36,9 +36,7 @@ public:
 
 	virtual void Handle(FStringBuilderBase& Result) override
 	{
-		MCPErrorCallback Error(Result);
-
-		MCPPackageMaker Maker(AssetPath, Error);
+		MCPPackageMaker Maker(AssetPath);
 		if (!Maker.Ok()) return;
 
 		// Resolve parent class — try C++ class first, then Blueprint asset
@@ -47,23 +45,23 @@ public:
 		if (!ParentClassObj)
 		{
 			MCPAssets<UBlueprint> ParentAssets;
-			if (!ParentAssets.Exact(ParentClass).AllContent().Errors(Error).ETwo().Load()) return;
+			if (!ParentAssets.Exact(ParentClass).AllContent().ETwo().Load()) return;
 			if (!ParentAssets.Objects().IsEmpty() && ParentAssets.Object()->GeneratedClass)
 				ParentClassObj = ParentAssets.Object()->GeneratedClass;
 		}
 
 		if (!ParentClassObj)
 		{
-			return Error.SetError(FString::Printf(
-				TEXT("Could not find parent class '%s'. Provide a C++ class name (e.g. 'Actor', 'Pawn') or Blueprint name."),
-				*ParentClass));
+			UMCPServer::Printf(TEXT("ERROR: Could not find parent class '%s'. Provide a C++ class name (e.g. 'Actor', 'Pawn') or Blueprint name.\n"),
+				*ParentClass);
+			return;
 		}
 
 		// Map blueprintType string to EBlueprintType
 		EBlueprintType BlueprintTypeEnum = BPTYPE_Normal;
 		if (!BlueprintType.IsEmpty())
 		{
-			if (!MCPUtils::StringToEnum(BlueprintType, BlueprintTypeEnum, Error, TEXT("BPTYPE_"))) return;
+			if (!MCPUtils::StringToEnum(BlueprintType, BlueprintTypeEnum, TEXT("BPTYPE_"))) return;
 		}
 
 		// For Interface type, parent must be UInterface
@@ -86,7 +84,8 @@ public:
 
 		if (!NewBP)
 		{
-			return Error.SetError(TEXT("FKismetEditorUtilities::CreateBlueprint returned null"));
+			UMCPServer::Print(TEXT("ERROR: FKismetEditorUtilities::CreateBlueprint returned null\n"));
+			return;
 		}
 
 		// Compile and save

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Blueprint_Diff.h

@@ -2,7 +2,7 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
 #include "Engine/Blueprint.h"
 #include "EdGraph/EdGraph.h"
@@ -41,11 +41,11 @@ public:
 	{
 		// Load both blueprints
 		MCPAssets<UBlueprint> AssetsA;
-		if (!AssetsA.Exact(BlueprintA).Errors(Result).ENone().ETwo().Load()) return;
+		if (!AssetsA.Exact(BlueprintA).ENone().ETwo().Load()) return;
 		UBlueprint* BPA = AssetsA.Object();
 
 		MCPAssets<UBlueprint> AssetsB;
-		if (!AssetsB.Exact(BlueprintB).Errors(Result).ENone().ETwo().Load()) return;
+		if (!AssetsB.Exact(BlueprintB).ENone().ETwo().Load()) return;
 		UBlueprint* BPB = AssetsB.Object();
 
 		// Gather graphs, optionally filtering by name

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Blueprint_RefreshAllNodes.h

@@ -2,7 +2,7 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
 #include "Engine/Blueprint.h"
 #include "EdGraph/EdGraph.h"
@@ -35,7 +35,7 @@ public:
 	{
 		// Load Blueprint
 		MCPAssets<UBlueprint> Assets;
-		if (!Assets.Exact(Blueprint).Errors(Result).ENone().ETwo().Load()) return;
+		if (!Assets.Exact(Blueprint).ENone().ETwo().Load()) return;
 		UBlueprint* BP = Assets.Object();
 
 		int32 GraphCount = MCPUtils::AllGraphs(BP).Num();

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Blueprint_RemoveFunctionParameter.h

@@ -3,7 +3,7 @@
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
 #include "K2Node_FunctionEntry.h"
 #include "K2Node_CustomEvent.h"
@@ -39,7 +39,7 @@ public:
 	virtual void Handle(FStringBuilderBase& Result) override
 	{
 		MCPAssets<UBlueprint> Assets;
-		if (!Assets.Exact(Blueprint).Errors(Result).ENone().ETwo().Load()) return;
+		if (!Assets.Exact(Blueprint).ENone().ETwo().Load()) return;
 		UBlueprint* BP = Assets.Object();
 
 		// Find the entry node (function entry or custom event)

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Blueprint_RemoveInterface.h

@@ -2,8 +2,9 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
+#include "MCPServer.h"
 #include "Engine/Blueprint.h"
 #include "Kismet2/BlueprintEditorUtils.h"
 #include "Blueprint_RemoveInterface.generated.h"
@@ -37,7 +38,7 @@ public:
 	virtual void Handle(FStringBuilderBase& Result) override
 	{
 		MCPAssets<UBlueprint> Assets;
-		if (!Assets.Exact(Blueprint).Errors(Result).ENone().ETwo().Load()) return;
+		if (!Assets.Exact(Blueprint).ENone().ETwo().Load()) return;
 		UBlueprint* BP = Assets.Object();
 
 		// Find the interface by name
@@ -54,12 +55,11 @@ public:
 
 		if (!FoundInterface)
 		{
-			MCPErrorCallback(Result).SetError(FString::Printf(
-				TEXT("Interface '%s' not found. Implemented interfaces: "), *InterfaceName));
+			UMCPServer::Printf(TEXT("ERROR: Interface '%s' not found. Implemented interfaces:\n"), *InterfaceName);
 			for (const FBPInterfaceDescription& IfaceDesc : BP->ImplementedInterfaces)
 			{
 				if (IfaceDesc.Interface)
-					Result.Appendf(TEXT("  %s\n"), *MCPUtils::FormatName(IfaceDesc.Interface));
+					UMCPServer::Printf(TEXT("  %s\n"), *MCPUtils::FormatName(IfaceDesc.Interface));
 			}
 			return;
 		}

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Blueprint_Reparent.h

@@ -3,8 +3,9 @@
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
+#include "MCPServer.h"
 #include "Engine/Blueprint.h"
 #include "Kismet2/BlueprintEditorUtils.h"
 #include "Kismet2/KismetEditorUtilities.h"
@@ -36,7 +37,7 @@ public:
 	{
 		// Load Blueprint
 		MCPAssets<UBlueprint> Assets;
-		if (!Assets.Exact(Blueprint).Errors(Result).ENone().ETwo().Load()) return;
+		if (!Assets.Exact(Blueprint).ENone().ETwo().Load()) return;
 		UBlueprint* BP = Assets.Object();
 
 		FString OldParentName = BP->ParentClass ? MCPUtils::FormatName(BP->ParentClass) : TEXT("None");
@@ -47,16 +48,15 @@ public:
 		if (!NewParentClassObj)
 		{
 			MCPAssets<UBlueprint> ParentAssets;
-			if (!ParentAssets.Exact(NewParentClass).AllContent().Errors(Result).ETwo().Load()) return;
+			if (!ParentAssets.Exact(NewParentClass).AllContent().ETwo().Load()) return;
 			if (!ParentAssets.Objects().IsEmpty() && ParentAssets.Object()->GeneratedClass)
 				NewParentClassObj = ParentAssets.Object()->GeneratedClass;
 		}
 
 		if (!NewParentClassObj)
 		{
-			MCPErrorCallback(Result).SetError(FString::Printf(
-				TEXT("Could not find class '%s'. Provide a C++ class name or Blueprint name."),
-				*NewParentClass));
+			UMCPServer::Printf(TEXT("ERROR: Could not find class '%s'. Provide a C++ class name or Blueprint name.\n"),
+				*NewParentClass);
 			return;
 		}
 

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Blueprint_Search.h

@@ -2,7 +2,7 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
 #include "Engine/Blueprint.h"
 #include "Engine/World.h"
@@ -39,7 +39,7 @@ public:
 	virtual void Handle(FStringBuilderBase& Result) override
 	{
 		MCPAssets<UObject> Assets;
-		Assets.NoScans().Substring(Query).Limit(500).Errors(Result);
+		Assets.NoScans().Substring(Query).Limit(500);
 		if (IncludeRegular) Assets.Scan<UBlueprint>();
 		if (IncludeLevel) Assets.Scan<UWorld>();
 		Assets.Info();

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Blueprint_SearchContents.h

@@ -2,7 +2,7 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
 #include "Engine/Blueprint.h"
 #include "Engine/World.h"

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Enum_Create.h

@@ -2,7 +2,7 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
 #include "Engine/UserDefinedEnum.h"
 #include "Kismet2/EnumEditorUtils.h"
@@ -34,9 +34,7 @@ public:
 
 	virtual void Handle(FStringBuilderBase& Result) override
 	{
-		MCPErrorCallback Error(Result);
-
-		MCPPackageMaker Maker(AssetPath, Error);
+		MCPPackageMaker Maker(AssetPath);
 		if (!Maker.Ok()) return;
 
 		TArray<FString> EnumValues;
@@ -47,7 +45,8 @@ public:
 		}
 		if (EnumValues.Num() == 0)
 		{
-			return Error.SetError(TEXT("Values must be a non-empty array of strings"));
+			UMCPServer::Print(TEXT("ERROR: Values must be a non-empty array of strings\n"));
+			return;
 		}
 
 		// Create the enum using AssetTools.

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/GraphNode_Create.h

@@ -61,7 +61,7 @@ public:
 		for (const TSharedPtr<FJsonValue>& NodeVal : Nodes.Array)
 		{
 			FSpawnNodeEntry Entry;
-			if (!MCPUtils::PopulateFromJson(FSpawnNodeEntry::StaticStruct(), &Entry, NodeVal, Result))
+			if (!MCPUtils::PopulateFromJson(FSpawnNodeEntry::StaticStruct(), &Entry, NodeVal))
 				continue;
 
 			// Find the action by exact full name

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/GraphNode_Delete.h

@@ -4,6 +4,7 @@
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
+#include "MCPServer.h"
 #include "EdGraph/EdGraph.h"
 #include "EdGraph/EdGraphNode.h"
 #include "MaterialGraph/MaterialGraphNode.h"
@@ -43,10 +44,9 @@ public:
 
 		if (!FoundNode->CanUserDeleteNode())
 		{
-			MCPErrorCallback Error(Result);
-			return Error.SetError(FString::Printf(
-				TEXT("Cannot delete node '%s' in graph '%s' — it is not deletable."),
-				*NodeTitle, *GraphName));
+			UMCPServer::Printf(TEXT("ERROR: Cannot delete node '%s' in graph '%s' — it is not deletable.\n"),
+				*NodeTitle, *GraphName);
+			return;
 		}
 
 		if (Cast<UMaterialGraphNode>(FoundNode))

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/GraphNode_SetDefaults.h

@@ -95,12 +95,12 @@ public:
 		UEdGraphNode* Node = F.Node(Entry.Node).Cast<UEdGraphNode>();
 		if (!Node) return;
 
-		MCPProperty P = MCPProperty::GetOneExactMatch(Node, CPF_Edit, Entry.Name, Result);
+		MCPProperty P = MCPProperty::GetOneExactMatch(Node, CPF_Edit, Entry.Name);
 		if (!P) return;
 
 		UMCPServer::AddTouchedObject(Node);
 
-		if (!P.SetText(Entry.Value, Result))
+		if (!P.SetText(Entry.Value))
 			return;
 	}
 
@@ -126,7 +126,7 @@ public:
 		for (const TSharedPtr<FJsonValue>& PinVal : Pins.Array)
 		{
 			FSetNodeDefaultEntry Entry;
-			if (!MCPUtils::PopulateFromJson(FSetNodeDefaultEntry::StaticStruct(), &Entry, PinVal, Result))
+			if (!MCPUtils::PopulateFromJson(FSetNodeDefaultEntry::StaticStruct(), &Entry, PinVal))
 				continue;
 
 			if (K2Schema)

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/GraphNode_SetPositions.h

@@ -57,7 +57,7 @@ public:
 		for (const TSharedPtr<FJsonValue>& NodeVal : Nodes.Array)
 		{
 			FMoveNodeEntry Entry;
-			if (!MCPUtils::PopulateFromJson(FMoveNodeEntry::StaticStruct(), &Entry, NodeVal, Result)) continue;
+			if (!MCPUtils::PopulateFromJson(FMoveNodeEntry::StaticStruct(), &Entry, NodeVal)) continue;
 
 			MCPFetcher FN(BP);
 			UEdGraphNode* Node = FN.Node(Entry.Node).Cast<UEdGraphNode>();

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/GraphPin_Connect.h

@@ -57,7 +57,7 @@ public:
 		for (const TSharedPtr<FJsonValue>& ConnVal : Connections.Array)
 		{
 			FConnectPinsEntry Entry;
-			if (!MCPUtils::PopulateFromJson(FConnectPinsEntry::StaticStruct(), &Entry, ConnVal, Result))
+			if (!MCPUtils::PopulateFromJson(FConnectPinsEntry::StaticStruct(), &Entry, ConnVal))
 				continue;
 
 			MCPFetcher FS(G);

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/GraphPin_Disconnect.h

@@ -57,7 +57,7 @@ public:
 		for (const TSharedPtr<FJsonValue>& DiscVal : Disconnections.Array)
 		{
 			FDisconnectPinEntry Entry;
-			if (!MCPUtils::PopulateFromJson(FDisconnectPinEntry::StaticStruct(), &Entry, DiscVal, Result)) continue;
+			if (!MCPUtils::PopulateFromJson(FDisconnectPinEntry::StaticStruct(), &Entry, DiscVal)) continue;
 
 			MCPFetcher FP(G);
 			UEdGraphPin* Pin = FP.Walk(Entry.Pin).Cast<UEdGraphPin>();

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/MaterialFunction_Create.h

@@ -2,7 +2,7 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
 #include "Materials/MaterialFunction.h"
 #include "Factories/MaterialFunctionFactoryNew.h"
@@ -33,9 +33,7 @@ public:
 
 	virtual void Handle(FStringBuilderBase& Result) override
 	{
-		MCPErrorCallback Error(Result);
-
-		MCPPackageMaker Maker(AssetPath, Error);
+		MCPPackageMaker Maker(AssetPath);
 		if (!Maker.Ok()) return;
 
 		// Create via IAssetTools + factory.

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/MaterialInstance_ClearParameter.h

@@ -44,7 +44,7 @@ public:
 
 		// Parse the association string.
 		EMaterialParameterAssociation Association;
-		if (!MCPUtils::ParseMaterialParameterAssociation(ParameterAssociation, Association, Result))
+		if (!MCPUtils::ParseMaterialParameterAssociation(ParameterAssociation, Association))
 			return;
 
 		FMaterialParameterInfo ParamID(*Parameter, Association, ParameterLayer);

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/MaterialInstance_Create.h

@@ -2,7 +2,7 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
 #include "Materials/Material.h"
 #include "Materials/MaterialInterface.h"
@@ -35,9 +35,7 @@ public:
 
 	virtual void Handle(FStringBuilderBase& Result) override
 	{
-		MCPErrorCallback Error(Result);
-
-		MCPPackageMaker Maker(AssetPath, Error);
+		MCPPackageMaker Maker(AssetPath);
 		if (!Maker.Ok()) return;
 
 		// Load parent material -- try as Material first, then as Material Instance.

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/MaterialInstance_SetParameter.h

@@ -48,7 +48,7 @@ public:
 
 		// Parse the association string.
 		EMaterialParameterAssociation Association;
-		if (!MCPUtils::ParseMaterialParameterAssociation(ParameterAssociation, Association, Result))
+		if (!MCPUtils::ParseMaterialParameterAssociation(ParameterAssociation, Association))
 			return;
 
 		// Build the parameter ID to look up.

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Material_Create.h

@@ -2,7 +2,7 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
 #include "Materials/Material.h"
 #include "MaterialDomain.h"
@@ -40,23 +40,21 @@ public:
 
 	virtual void Handle(FStringBuilderBase& Result) override
 	{
-		MCPErrorCallback Error(Result);
-
-		MCPPackageMaker Maker(AssetPath, Error);
+		MCPPackageMaker Maker(AssetPath);
 		if (!Maker.Ok()) return;
 
 		// Parse optional enum properties before creating the asset.
 		EMaterialDomain ParsedDomain = MD_Surface;
 		if (!Domain.IsEmpty())
 		{
-			if (!MCPUtils::StringToEnum(Domain, ParsedDomain, Error, TEXT("MD_")))
+			if (!MCPUtils::StringToEnum(Domain, ParsedDomain, TEXT("MD_")))
 				return;
 		}
 
 		EBlendMode ParsedBlendMode = BLEND_Opaque;
 		if (!BlendMode.IsEmpty())
 		{
-			if (!MCPUtils::StringToEnum(BlendMode, ParsedBlendMode, Error, TEXT("BLEND_")))
+			if (!MCPUtils::StringToEnum(BlendMode, ParsedBlendMode, TEXT("BLEND_")))
 				return;
 		}
 

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Property_Get.h

@@ -35,7 +35,7 @@ public:
 		UObject* Template = F.Walk(Path).Template().Cast<UObject>();
 		if (!Template) return;
 
-		MCPProperty P = MCPProperty::GetOneExactMatch(Template, CPF_Edit, Property, Result);
+		MCPProperty P = MCPProperty::GetOneExactMatch(Template, CPF_Edit, Property);
 		if (!P) return;
 
 		Result.Append(P.GetText());

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Property_Set.h

@@ -47,7 +47,7 @@ public:
 		TArray<TPair<MCPProperty, FString>> Resolved;
 		for (const auto& Pair : Properties.Json->Values)
 		{
-			MCPProperty P = MCPProperty::GetOneExactMatch(Template, CPF_Edit, Pair.Key, Result);
+			MCPProperty P = MCPProperty::GetOneExactMatch(Template, CPF_Edit, Pair.Key);
 			if (!P) return;
 
 			FString ValueStr;
@@ -63,7 +63,7 @@ public:
 		int32 SuccessCount = 0;
 		for (auto& [P, ValueStr] : Resolved)
 		{
-			if (!P.SetText(ValueStr, Result))
+			if (!P.SetText(ValueStr))
 				continue;
 			SuccessCount++;
 		}

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/StateMachine_AddState.h

@@ -2,7 +2,7 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
 #include "EdGraph/EdGraph.h"
@@ -65,7 +65,7 @@ public:
 		}
 
 		// Check for duplicate state name
-		if (MCPUtils::FindStateByName(SMGraph, StateName, nullptr))
+		if (MCPUtils::FindStateByName(SMGraph, StateName))
 		{
 			Result.Appendf(TEXT("ERROR: State '%s' already exists in %s\n"), *StateName, *MCPUtils::FormatName(SMGraph));
 			return;
@@ -94,7 +94,7 @@ public:
 		if (!AnimationAsset.IsEmpty() && NewState->GetBoundGraph())
 		{
 			MCPAssets<UAnimSequence> AnimAssets;
-			if (!AnimAssets.Exact(AnimationAsset).Errors(Result).ENone().ETwo().Load()) return;
+			if (!AnimAssets.Exact(AnimationAsset).ENone().ETwo().Load()) return;
 
 			UAnimGraphNode_SequencePlayer* SeqNode = NewObject<UAnimGraphNode_SequencePlayer>(NewState->GetBoundGraph());
 			SeqNode->CreateNewGuid();

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/StateMachine_AddTransition.h

@@ -2,7 +2,7 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
 #include "Kismet2/KismetEditorUtilities.h"
 #include "Animation/AnimBlueprint.h"
@@ -51,7 +51,7 @@ public:
 	virtual void Handle(FStringBuilderBase& Result) override
 	{
 		MCPAssets<UAnimBlueprint> Assets;
-		if (!Assets.Exact(Blueprint).Errors(Result).ENone().ETwo().Load()) return;
+		if (!Assets.Exact(Blueprint).ENone().ETwo().Load()) return;
 		UAnimBlueprint* AnimBP = Assets.Object();
 
 		UAnimationStateMachineGraph* SMGraph = MCPUtils::FindStateMachineGraph(AnimBP, Graph);
@@ -61,10 +61,10 @@ public:
 			return;
 		}
 
-		UAnimStateNode* FromStateNode = MCPUtils::FindStateByName(SMGraph, FromState, Result);
+		UAnimStateNode* FromStateNode = MCPUtils::FindStateByName(SMGraph, FromState);
 		if (!FromStateNode) return;
 
-		UAnimStateNode* ToStateNode = MCPUtils::FindStateByName(SMGraph, ToState, Result);
+		UAnimStateNode* ToStateNode = MCPUtils::FindStateByName(SMGraph, ToState);
 		if (!ToStateNode) return;
 
 		// Create transition node

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/StateMachine_RemoveState.h

@@ -52,7 +52,7 @@ public:
 		}
 
 		// Find the state node
-		UAnimStateNode* StateNode = MCPUtils::FindStateByName(SMGraph, StateName, Result);
+		UAnimStateNode* StateNode = MCPUtils::FindStateByName(SMGraph, StateName);
 		if (!StateNode) return;
 
 		// Collect and remove transitions connected to this state

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/StateMachine_SetAnimation.h

@@ -2,7 +2,7 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
 #include "EdGraph/EdGraph.h"
@@ -59,7 +59,7 @@ public:
 		}
 
 		// Find the target state
-		UAnimStateNode* StateNode = MCPUtils::FindStateByName(SMGraph, StateName, Result);
+		UAnimStateNode* StateNode = MCPUtils::FindStateByName(SMGraph, StateName);
 		if (!StateNode) return;
 
 		UEdGraph* InnerGraph = StateNode->GetBoundGraph();
@@ -71,7 +71,7 @@ public:
 
 		// Find the animation asset
 		MCPAssets<UAnimSequence> AnimAssets;
-		if (!AnimAssets.Exact(AnimationAsset).Errors(Result).ENone().ETwo().Load()) return;
+		if (!AnimAssets.Exact(AnimationAsset).ENone().ETwo().Load()) return;
 		UAnimSequence* AnimSeq = AnimAssets.Object();
 
 		// Find existing SequencePlayer or create one

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/StateMachine_SetBlendSpace.h

@@ -2,7 +2,7 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
 #include "EdGraph/EdGraph.h"
@@ -57,14 +57,14 @@ public:
 	{
 		// Load the anim blueprint
 		MCPAssets<UAnimBlueprint> Assets;
-		if (!Assets.Exact(Blueprint).Errors(Result).ENone().ETwo().Load()) return;
+		if (!Assets.Exact(Blueprint).ENone().ETwo().Load()) return;
 		UAnimBlueprint* AnimBP = Assets.Object();
 
 		// Find the state machine graph and state
 		UAnimationStateMachineGraph* SMGraph = MCPUtils::FindStateMachineGraph(AnimBP, Graph);
 		if (!SMGraph) { Result.Appendf(TEXT("ERROR: State machine graph '%s' not found\n"), *Graph); return; }
 
-		UAnimStateNode* StateNode = MCPUtils::FindStateByName(SMGraph, StateName, Result);
+		UAnimStateNode* StateNode = MCPUtils::FindStateByName(SMGraph, StateName);
 		if (!StateNode) return;
 
 		UEdGraph* InnerGraph = StateNode->GetBoundGraph();
@@ -72,7 +72,7 @@ public:
 
 		// Load the blend space asset
 		MCPAssets<UBlendSpace> BlendSpaceAssets;
-		if (!BlendSpaceAssets.Exact(BlendSpace).Errors(Result).ENone().ETwo().Load()) return;
+		if (!BlendSpaceAssets.Exact(BlendSpace).ENone().ETwo().Load()) return;
 		UBlendSpace* BlendSpaceAsset = BlendSpaceAssets.Object();
 
 		// Find existing BlendSpacePlayer or create one

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/StateMachine_SetTransitionRule.h

@@ -2,7 +2,7 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
 #include "Kismet2/KismetEditorUtilities.h"
 #include "Animation/AnimBlueprint.h"
@@ -56,7 +56,7 @@ public:
 	virtual void Handle(FStringBuilderBase& Result) override
 	{
 		MCPAssets<UAnimBlueprint> Assets;
-		if (!Assets.Exact(Blueprint).Errors(Result).ENone().ETwo().Load()) return;
+		if (!Assets.Exact(Blueprint).ENone().ETwo().Load()) return;
 		UAnimBlueprint* AnimBP = Assets.Object();
 
 		UAnimationStateMachineGraph* SMGraph = MCPUtils::FindStateMachineGraph(AnimBP, Graph);

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Struct_Create.h

@@ -2,7 +2,7 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "MCPUtils.h"
 #include "StructUtils/UserDefinedStruct.h"
 #include "Kismet2/BlueprintEditorUtils.h"
@@ -47,9 +47,7 @@ public:
 
 	virtual void Handle(FStringBuilderBase& Result) override
 	{
-		MCPErrorCallback Error(Result);
-
-		MCPPackageMaker Maker(AssetPath, Error);
+		MCPPackageMaker Maker(AssetPath);
 		if (!Maker.Ok()) return;
 
 		// Create the struct using the AssetTools factory.
@@ -61,11 +59,11 @@ public:
 		for (const TSharedPtr<FJsonValue>& PropVal : Properties.Array)
 		{
 			FStructPropertyEntry Entry;
-			if (!MCPUtils::PopulateFromJson(FStructPropertyEntry::StaticStruct(), &Entry, PropVal, Result)) return;
+			if (!MCPUtils::PopulateFromJson(FStructPropertyEntry::StaticStruct(), &Entry, PropVal)) return;
 			if (Entry.Name.IsEmpty() || Entry.Type.IsEmpty()) continue;
 
 			FEdGraphPinType PinType;
-			if (!MCPUtils::ResolveTypeFromString(Entry.Type, PinType, Result))
+			if (!MCPUtils::ResolveTypeFromString(Entry.Type, PinType))
 				continue;
 
 			// Snapshot existing GUIDs so we can find the newly added one.

Plugins/BlueprintMCP/Source/BlueprintMCP/Private/MCPAssets.cpp

@@ -1,4 +1,5 @@
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
+#include "MCPServer.h"
 #include "Engine/Blueprint.h"
 #include "Engine/World.h"
 #include "Engine/Level.h"
@@ -46,12 +47,6 @@ MCPAssetsBase& MCPAssetsBase::AllContent()
 	return *this;
 }
 
-MCPAssetsBase& MCPAssetsBase::Errors(MCPErrorCallback InCB)
-{
-	ErrorCB = InCB;
-	return *this;
-}
-
 
 bool MCPAssetsBase::Info()
 {
@@ -171,5 +166,5 @@ void MCPAssetsBase::SetError(const FString &Msg)
 {
 	AssetResults.Empty();
 	UObjectResults.Empty();
-	ErrorCB.SetError(Msg);
+	UMCPServer::Printf(TEXT("ERROR: %s\n"), *Msg);
 }

Plugins/BlueprintMCP/Source/BlueprintMCP/Private/MCPProperty.cpp

@@ -1,5 +1,6 @@
 #include "MCPProperty.h"
 #include "MCPUtils.h"
+#include "MCPServer.h"
 #include "Materials/MaterialExpression.h"
 #include "MaterialGraph/MaterialGraphNode.h"
 
@@ -14,14 +15,14 @@ FString MCPProperty::GetText() const
 	return Result;
 }
 
-bool MCPProperty::SetText(const FString& Value, MCPErrorCallback Error)
+bool MCPProperty::SetText(const FString& Value)
 {
 	void* ValuePtr = Prop->ContainerPtrToValuePtr<void>(Container);
 	const TCHAR* ImportResult = Prop->ImportText_Direct(*Value, ValuePtr, nullptr, PPF_None);
 	if (!ImportResult)
 	{
-		Error.SetError(FString::Printf(TEXT("Failed to parse '%s' for property '%s' (type: %s)"),
-			*Value, *MCPUtils::FormatName(Prop), *Prop->GetCPPType()));
+		UMCPServer::Printf(TEXT("ERROR: Failed to parse '%s' for property '%s' (type: %s)\n"),
+			*Value, *MCPUtils::FormatName(Prop), *Prop->GetCPPType());
 		return false;
 	}
 
@@ -82,19 +83,19 @@ TArray<MCPProperty> MCPProperty::GetAllExactMatch(UObject* Obj, EPropertyFlags F
 	return Result;
 }
 
-MCPProperty MCPProperty::GetOneExactMatch(UObject* Obj, EPropertyFlags Flags, const FString& Name, MCPErrorCallback Error)
+MCPProperty MCPProperty::GetOneExactMatch(UObject* Obj, EPropertyFlags Flags, const FString& Name)
 {
 	TArray<MCPProperty> Matches = GetAllExactMatch(Obj, Flags, Name);
 	if (Matches.Num() == 0)
 	{
-		Error.SetError(FString::Printf(TEXT("Property '%s' not found on %s"),
-			*Name, *MCPUtils::FormatName(Obj->GetClass())));
+		UMCPServer::Printf(TEXT("ERROR: Property '%s' not found on %s\n"),
+			*Name, *MCPUtils::FormatName(Obj->GetClass()));
 		return MCPProperty();
 	}
 	if (Matches.Num() > 1)
 	{
-		Error.SetError(FString::Printf(TEXT("Ambiguous property '%s' on %s"),
-			*Name, *MCPUtils::FormatName(Obj->GetClass())));
+		UMCPServer::Printf(TEXT("ERROR: Ambiguous property '%s' on %s\n"),
+			*Name, *MCPUtils::FormatName(Obj->GetClass()));
 		return MCPProperty();
 	}
 	return Matches[0];

Plugins/BlueprintMCP/Source/BlueprintMCP/Private/MCPServer.cpp

@@ -2,7 +2,7 @@
 #include "MCPHandler.h"
 #include "LogCapture.h"
 #include "MCPUtils.h"
-#include "MCPAssetFinder.h"
+#include "MCPAssets.h"
 #include "UObject/StrongObjectPtr.h"
 #include "Materials/MaterialExpression.h"
 #include "AssetRegistry/AssetRegistryModule.h"
@@ -289,12 +289,14 @@ FString UMCPServer::HandleRequest(const FString& Line)
 	IMCPHandler* Handler = Cast<IMCPHandler>(HandlerObj.Get());
 
 	// Populate the handler object with the request parameters.
-	TStringBuilder<4096> PopulateError;
-	if (!MCPUtils::PopulateFromJson(HandlerObj->GetClass(), HandlerObj.Get(), &*Request, PopulateError))
+	HandlerOutput.Reset();
+	if (!MCPUtils::PopulateFromJson(HandlerObj->GetClass(), HandlerObj.Get(), &*Request))
 	{
-		PopulateError.Append(TEXT("\nUsage:\n"));
-		MCPUtils::FormatCommandHelp(*HandlerClass, PopulateError);
-		return PopulateError.ToString();
+		HandlerOutput.Append(TEXT("\nUsage:\n"));
+		MCPUtils::FormatCommandHelp(*HandlerClass, HandlerOutput);
+		FString Result = HandlerOutput.ToString();
+		HandlerOutput.Reset();
+		return Result;
 	}
 
 	// Invoke the handler with log capture.

Plugins/BlueprintMCP/Source/BlueprintMCP/Private/MCPUtils.cpp

@@ -1,4 +1,5 @@
 #include "MCPUtils.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "Dom/JsonValue.h"
 #include "Serialization/JsonReader.h"
@@ -90,22 +91,6 @@ extern int32 TrySavePackageSEH(
 	FSavePackageArgs* SaveArgs, ESavePackageResult* OutResult);
 #endif
 
-// ============================================================
-// MCPErrorCallback
-// ============================================================
-
-MCPErrorCallback::MCPErrorCallback(std::nullptr_t)
-	: Func([](const FString&) {})
-{}
-
-MCPErrorCallback::MCPErrorCallback(FString& OutError)
-	: Func([&OutError](const FString& Msg) { OutError = Msg; })
-{}
-
-MCPErrorCallback::MCPErrorCallback(FStringBuilderBase& OutResult)
-	: Func([&OutResult](const FString& Msg) { OutResult.Appendf(TEXT("ERROR: %s\n"), *Msg); })
-{}
-
 // ============================================================
 // Name Formatting
 // ============================================================
@@ -343,12 +328,12 @@ FString MCPUtils::EnumToString(UEnum* Enum, int64 Value, const FString& Prefix)
 	return Full;
 }
 
-bool MCPUtils::StringToEnum(UEnum* Enum, const FString& Str, int64& OutValue, MCPErrorCallback Error, const FString& Prefix)
+bool MCPUtils::StringToEnum(UEnum* Enum, const FString& Str, int64& OutValue, const FString& Prefix)
 {
 	OutValue = Enum->GetValueByNameString(Prefix + Str);
 	if (OutValue == INDEX_NONE)
 	{
-		Error.SetError(FString::Printf(TEXT("Invalid value '%s' for %s"), *Str, *Enum->GetName()));
+		UMCPServer::Printf(TEXT("ERROR: Invalid value '%s' for %s\n"), *Str, *Enum->GetName());
 		return false;
 	}
 	return true;
@@ -541,7 +526,7 @@ UClass* MCPUtils::FindClassByName(const FString& ClassName)
 }
 
 bool MCPUtils::ResolveTypeFromString(
-	const FString& TypeName, FEdGraphPinType& OutPinType, MCPErrorCallback Error)
+	const FString& TypeName, FEdGraphPinType& OutPinType)
 {
 	FString TypeLower = TypeName.ToLower();
 
@@ -614,7 +599,7 @@ bool MCPUtils::ResolveTypeFromString(
 		UClass* FoundClass = FindClassByName(ClassName);
 		if (!FoundClass)
 		{
-			Error.SetError(FString::Printf(TEXT("Class '%s' not found for object reference type"), *ClassName));
+			UMCPServer::Printf(TEXT("ERROR: Class '%s' not found for object reference type\n"), *ClassName);
 			return false;
 		}
 		OutPinType.PinCategory = UEdGraphSchema_K2::PC_Object;
@@ -626,7 +611,7 @@ bool MCPUtils::ResolveTypeFromString(
 		UClass* FoundClass = FindClassByName(ClassName);
 		if (!FoundClass)
 		{
-			Error.SetError(FString::Printf(TEXT("Class '%s' not found for soft object reference type"), *ClassName));
+			UMCPServer::Printf(TEXT("ERROR: Class '%s' not found for soft object reference type\n"), *ClassName);
 			return false;
 		}
 		OutPinType.PinCategory = UEdGraphSchema_K2::PC_SoftObject;
@@ -638,7 +623,7 @@ bool MCPUtils::ResolveTypeFromString(
 		UClass* FoundClass = FindClassByName(ClassName);
 		if (!FoundClass)
 		{
-			Error.SetError(FString::Printf(TEXT("Class '%s' not found for class reference type (TSubclassOf)"), *ClassName));
+			UMCPServer::Printf(TEXT("ERROR: Class '%s' not found for class reference type (TSubclassOf)\n"), *ClassName);
 			return false;
 		}
 		OutPinType.PinCategory = UEdGraphSchema_K2::PC_Class;
@@ -650,7 +635,7 @@ bool MCPUtils::ResolveTypeFromString(
 		UClass* FoundClass = FindClassByName(ClassName);
 		if (!FoundClass)
 		{
-			Error.SetError(FString::Printf(TEXT("Class '%s' not found for soft class reference type"), *ClassName));
+			UMCPServer::Printf(TEXT("ERROR: Class '%s' not found for soft class reference type\n"), *ClassName);
 			return false;
 		}
 		OutPinType.PinCategory = UEdGraphSchema_K2::PC_SoftClass;
@@ -662,7 +647,7 @@ bool MCPUtils::ResolveTypeFromString(
 		UClass* FoundClass = FindClassByName(ClassName);
 		if (!FoundClass)
 		{
-			Error.SetError(FString::Printf(TEXT("Class '%s' not found for interface reference type"), *ClassName));
+			UMCPServer::Printf(TEXT("ERROR: Class '%s' not found for interface reference type\n"), *ClassName);
 			return false;
 		}
 		OutPinType.PinCategory = UEdGraphSchema_K2::PC_Interface;
@@ -738,9 +723,9 @@ bool MCPUtils::ResolveTypeFromString(
 			}
 			else
 			{
-				Error.SetError(FString::Printf(
-					TEXT("Unknown type '%s'. Use: bool, int, float, string, name, text, byte, vector, rotator, transform, object, a struct/enum name (e.g. FVector, EMyEnum), or colon syntax for references (object:Actor, softobject:Actor, class:Actor, softclass:Actor, interface:MyInterface)"),
-					*TypeName));
+				UMCPServer::Printf(
+					TEXT("ERROR: Unknown type '%s'. Use: bool, int, float, string, name, text, byte, vector, rotator, transform, object, a struct/enum name (e.g. FVector, EMyEnum), or colon syntax for references (object:Actor, softobject:Actor, class:Actor, softclass:Actor, interface:MyInterface)\n"),
+					*TypeName);
 				return false;
 			}
 		}
@@ -798,54 +783,6 @@ UMaterial* MCPUtils::ReplaceMaterialWithTransientCopy(UMaterial* Material)
 	return Material;
 }
 
-// ============================================================
-// PreEdit / PostEdit
-// ============================================================
-
-void MCPUtils::PreEdit(const TArray<UObject*>& Objects)
-{
-	for (UObject* Obj : Objects)
-		Obj->PreEditChange(nullptr);
-}
-
-void MCPUtils::PostEdit(const TArray<UObject*>& Objects)
-{
-	TSet<UEdGraphNode*> Nodes;
-	TSet<UEdGraph*> Graphs;
-	TSet<UMaterial*> Materials;
-	TSet<UBlueprint*> Blueprints;
-	for (int32 i = Objects.Num() - 1; i >= 0; --i)
-	{
-		UObject* Obj = Objects[i];
-		Obj->PostEditChange();
-		Obj->MarkPackageDirty();
-
-		if (UEdGraphNode* Node = Cast<UEdGraphNode>(Obj))
-			Nodes.Add(Node);
-
-		if (UEdGraph* Graph = Cast<UEdGraph>(Obj))
-			Graphs.Add(Graph);
-
-		if (UBlueprint* BP = Cast<UBlueprint>(Obj))
-			Blueprints.Add(BP);
-
-		if (UMaterialInterface* MatIface = Cast<UMaterialInterface>(Obj))
-			if (UMaterial* BaseMat = MatIface->GetMaterial())
-				Materials.Add(BaseMat);
-	}
-	for (UEdGraphNode* Node : Nodes)
-		Node->ReconstructNode();
-	for (UEdGraph* Graph : Graphs)
-		Graph->NotifyGraphChanged();
-	for (UMaterial *Material : Materials)
-		UMaterialEditingLibrary::RebuildMaterialInstanceEditors(Material);
-	for (UBlueprint *Blueprint : Blueprints)
-		FBlueprintEditorUtils::MarkBlueprintAsStructurallyModified(Blueprint);
-
-	if (GEditor)
-		GEditor->RedrawAllViewports();
-}
-
 
 TMap<FMaterialParameterInfo, FMaterialParameterMetadata> MCPUtils::GetMaterialParameters(UMaterialInterface* Material)
 {
@@ -860,7 +797,7 @@ TMap<FMaterialParameterInfo, FMaterialParameterMetadata> MCPUtils::GetMaterialPa
 	return Result;
 }
 
-bool MCPUtils::ParseMaterialParameterAssociation(const FString& Str, EMaterialParameterAssociation& OutAssociation, MCPErrorCallback Error)
+bool MCPUtils::ParseMaterialParameterAssociation(const FString& Str, EMaterialParameterAssociation& OutAssociation)
 {
 	if (Str.Equals(TEXT("Global"), ESearchCase::IgnoreCase))
 		OutAssociation = GlobalParameter;
@@ -870,7 +807,7 @@ bool MCPUtils::ParseMaterialParameterAssociation(const FString& Str, EMaterialPa
 		OutAssociation = BlendParameter;
 	else
 	{
-		Error.SetError(FString::Printf(TEXT("Invalid ParameterAssociation '%s' (expected 'Global', 'Layer', or 'Blend')"), *Str));
+		UMCPServer::Printf(TEXT("ERROR: Invalid ParameterAssociation '%s' (expected 'Global', 'Layer', or 'Blend')\n"), *Str);
 		return false;
 	}
 	return true;
@@ -984,7 +921,7 @@ UAnimationStateMachineGraph* MCPUtils::FindStateMachineGraph(UBlueprint* BP, con
 	return nullptr;
 }
 
-UAnimStateNode* MCPUtils::FindStateByName(UAnimationStateMachineGraph* SMGraph, const FString& StateName, MCPErrorCallback Error)
+UAnimStateNode* MCPUtils::FindStateByName(UAnimationStateMachineGraph* SMGraph, const FString& StateName)
 {
 	for (UEdGraphNode* Node : SMGraph->Nodes)
 	{
@@ -996,7 +933,7 @@ UAnimStateNode* MCPUtils::FindStateByName(UAnimationStateMachineGraph* SMGraph,
 			}
 		}
 	}
-	Error.SetError(FString::Printf(TEXT("State '%s' not found in graph '%s'"), *StateName, *SMGraph->GetName()));
+	UMCPServer::Printf(TEXT("ERROR: State '%s' not found in graph '%s'\n"), *StateName, *SMGraph->GetName());
 	return nullptr;
 }
 
@@ -1229,22 +1166,20 @@ FString MCPUtils::SetPropertyFromJson(
 bool MCPUtils::PopulateFromJson(
 	UStruct* StructType,
 	void* Container,
-	const TSharedPtr<FJsonValue>& JsonValue,
-	MCPErrorCallback Error)
+	const TSharedPtr<FJsonValue>& JsonValue)
 {
 	if (!JsonValue.IsValid() || (JsonValue->Type != EJson::Object))
 	{
-		Error.SetError(TEXT("Expected a JSON object"));
+		UMCPServer::Print(TEXT("ERROR: Expected a JSON object\n"));
 		return false;
 	}
-	return PopulateFromJson(StructType, Container, JsonValue->AsObject().Get(), Error);
+	return PopulateFromJson(StructType, Container, JsonValue->AsObject().Get());
 }
 
 bool MCPUtils::PopulateFromJson(
 	UStruct* StructType,
 	void* Container,
-	const FJsonObject* Json,
-	MCPErrorCallback Error)
+	const FJsonObject* Json)
 {
 	// Build a set of known property names (as JSON keys) for the unknown-field check.
 	TSet<FString> KnownKeys;
@@ -1262,7 +1197,7 @@ bool MCPUtils::PopulateFromJson(
 	{
 		if (!KnownKeys.Contains(KV.Key))
 		{
-			Error.SetError(FString::Printf(TEXT("Unknown parameter '%s'"), *KV.Key));
+			UMCPServer::Printf(TEXT("ERROR: Unknown parameter '%s'\n"), *KV.Key);
 			return false;
 		}
 	}
@@ -1277,7 +1212,7 @@ bool MCPUtils::PopulateFromJson(
 		{
 			if (!bOptional)
 			{
-				Error.SetError(FString::Printf(TEXT("Missing required parameter '%s'"), *JsonKey));
+				UMCPServer::Printf(TEXT("ERROR: Missing required parameter '%s'\n"), *JsonKey);
 				return false;
 			}
 			continue;
@@ -1286,7 +1221,7 @@ bool MCPUtils::PopulateFromJson(
 		FString PropError = SetPropertyFromJson(Container, Prop, JsonKey, Json);
 		if (!PropError.IsEmpty())
 		{
-			Error.SetError(PropError);
+			UMCPServer::Printf(TEXT("ERROR: %s\n"), *PropError);
 			return false;
 		}
 	}
@@ -1369,11 +1304,11 @@ FString MCPUtils::FormatPropertyType(FProperty* Prop)
 // FindPropertyByName
 // ============================================================
 
-FProperty* MCPUtils::FindPropertyByName(UObject* Obj, const FString& Name, MCPErrorCallback Error)
+FProperty* MCPUtils::FindPropertyByName(UObject* Obj, const FString& Name)
 {
 	if (!Obj)
 	{
-		Error.SetError(TEXT("Object is null"));
+		UMCPServer::Print(TEXT("ERROR: Object is null\n"));
 		return nullptr;
 	}
 
@@ -1383,14 +1318,14 @@ FProperty* MCPUtils::FindPropertyByName(UObject* Obj, const FString& Name, MCPEr
 		if (!Identifies(Name, *PropIt)) continue;
 		if (Found)
 		{
-			Error.SetError(FString::Printf(TEXT("Ambiguous property '%s' on %s"), *Name, *FormatName(Obj->GetClass())));
+			UMCPServer::Printf(TEXT("ERROR: Ambiguous property '%s' on %s\n"), *Name, *FormatName(Obj->GetClass()));
 			return nullptr;
 		}
 		Found = *PropIt;
 	}
 
 	if (!Found)
-		Error.SetError(FString::Printf(TEXT("Property '%s' not found on %s"), *Name, *FormatName(Obj->GetClass())));
+		UMCPServer::Printf(TEXT("ERROR: Property '%s' not found on %s\n"), *Name, *FormatName(Obj->GetClass()));
 
 	return Found;
 }
@@ -1411,27 +1346,27 @@ FString MCPUtils::GetPropertyValueText(UObject* Container, FProperty* Prop)
 // SetPropertyValueText
 // ============================================================
 
-bool MCPUtils::SetPropertyValueText(UObject* Container, FProperty* Prop, const FString& Value, MCPErrorCallback Error)
+bool MCPUtils::SetPropertyValueText(UObject* Container, FProperty* Prop, const FString& Value)
 {
 	void* ValuePtr = Prop->ContainerPtrToValuePtr<void>(Container);
 	const TCHAR* ImportResult = Prop->ImportText_Direct(*Value, ValuePtr, Container, PPF_None);
 	if (!ImportResult)
 	{
-		Error.SetError(FString::Printf(TEXT("Failed to parse '%s' for property '%s' (type: %s)"),
-			*Value, *FormatName(Prop), *Prop->GetCPPType()));
+		UMCPServer::Printf(TEXT("ERROR: Failed to parse '%s' for property '%s' (type: %s)\n"),
+			*Value, *FormatName(Prop), *Prop->GetCPPType());
 		return false;
 	}
 	return true;
 }
 
-bool MCPUtils::SetPropertyValueText(void* Container, FProperty* Prop, const FString& Value, UObject* Owner, MCPErrorCallback Error)
+bool MCPUtils::SetPropertyValueText(void* Container, FProperty* Prop, const FString& Value, UObject* Owner)
 {
 	void* ValuePtr = Prop->ContainerPtrToValuePtr<void>(Container);
 	const TCHAR* ImportResult = Prop->ImportText_Direct(*Value, ValuePtr, Owner, PPF_None);
 	if (!ImportResult)
 	{
-		Error.SetError(FString::Printf(TEXT("Failed to parse '%s' for property '%s' (type: %s)"),
-			*Value, *FormatName(Prop), *Prop->GetCPPType()));
+		UMCPServer::Printf(TEXT("ERROR: Failed to parse '%s' for property '%s' (type: %s)\n"),
+			*Value, *FormatName(Prop), *Prop->GetCPPType());
 		return false;
 	}
 	return true;

Plugins/BlueprintMCP/Source/BlueprintMCP/Public/MCPAssets.h

@@ -60,12 +60,7 @@ struct FARFilter;
 //   Assets.EAny() - it's an error if anything is found
 //   Assets.ETwo() - it's an error if two or more are found
 //
-// Errors can be stored in variables, or in string builders,
-// or in json trees.  This example tells it to put error
-// messages into a string variable:
-//
-//   FString ErrorMessage;
-//   Assets.Errors(ErrorMessage)
+// Errors are reported via UMCPServer::Printf.
 //
 // Once the Assets object is configured, it's time to scan
 // the assets.  Use 'Info' if you just want to see
@@ -87,7 +82,7 @@ struct FARFilter;
 //
 // MCPAssets configuration methods can be chained:
 //
-//   Assets.Limit(100).Errors(ErrMsg).ENone().ETwo();
+//   Assets.Limit(100).ENone().ETwo();
 //
 ////////////////////////////////////////////////////////////
 
@@ -102,7 +97,6 @@ public:
 	MCPAssetsBase& Limit(int32 Count) { MaxResults = Count; return *this; }
 	MCPAssetsBase& NoDerived();
 	MCPAssetsBase& AllContent();
-	MCPAssetsBase& Errors(MCPErrorCallback InCB);
 	MCPAssetsBase& EAny() { bErrorIfAny = true; return *this; }
 	MCPAssetsBase& ENone() { bErrorIfNone = true; return *this; }
 	MCPAssetsBase& ETwo() { bErrorIfTwo = true; return *this; }
@@ -135,7 +129,6 @@ protected:
 	bool bErrorIfNone = false;
 	bool bErrorIfTwo = false;
 	int32 MaxResults = 50;
-	MCPErrorCallback ErrorCB = MCPErrorCallback(nullptr);
 };
 
 

Plugins/BlueprintMCP/Source/BlueprintMCP/Public/MCPPackageMaker.h

@@ -1,7 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
-#include "MCPUtils.h"
+#include "MCPServer.h"
 #include "UObject/Package.h"
 #include "AssetToolsModule.h"
 #include "IAssetTools.h"
@@ -12,14 +12,13 @@
 class MCPPackageMaker
 {
 public:
-	MCPPackageMaker(const FString& InFullPath, MCPErrorCallback InError)
+	MCPPackageMaker(const FString& InFullPath)
 		: FullPath(InFullPath)
-		, Error(InError)
 	{
 		// Path must start with /Game.
 		if (!FullPath.StartsWith(TEXT("/Game")))
 		{
-			Error.SetError(FString::Printf(TEXT("Package path '%s' must start with '/Game'"), *FullPath));
+			UMCPServer::Printf(TEXT("ERROR: Package path '%s' must start with '/Game'\n"), *FullPath);
 			bError = true;
 			return;
 		}
@@ -27,7 +26,7 @@ public:
 		// Check for an existing asset at this path.
 		if (FindObject<UPackage>(nullptr, *FullPath))
 		{
-			Error.SetError(FString::Printf(TEXT("An asset already exists at '%s'"), *FullPath));
+			UMCPServer::Printf(TEXT("ERROR: An asset already exists at '%s'\n"), *FullPath);
 			bError = true;
 			return;
 		}
@@ -41,7 +40,7 @@ public:
 		Pkg = CreatePackage(*FullPath);
 		if (!Pkg)
 		{
-			Error.SetError(FString::Printf(TEXT("Failed to create package at '%s'"), *FullPath));
+			UMCPServer::Printf(TEXT("ERROR: Failed to create package at '%s'\n"), *FullPath);
 			bError = true;
 			return false;
 		}
@@ -63,7 +62,7 @@ public:
 		AssetClass* Result = Cast<AssetClass>(NewAsset);
 		if (!Result)
 		{
-			Error.SetError(FString::Printf(TEXT("Failed to create asset at '%s'"), *FullPath));
+			UMCPServer::Printf(TEXT("ERROR: Failed to create asset at '%s'\n"), *FullPath);
 			bError = true;
 		}
 		return Result;
@@ -71,7 +70,6 @@ public:
 
 private:
 	FString FullPath;
-	MCPErrorCallback Error;
 	UPackage* Pkg = nullptr;
 	bool bError = false;
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Public/MCPProperty.h

@@ -14,7 +14,7 @@ struct MCPProperty
 	MCPProperty(FProperty* InProp, void* Container);
 
 	FString GetText() const;
-	bool SetText(const FString& Value, MCPErrorCallback Error = nullptr);
+	bool SetText(const FString& Value);
 
 	explicit operator bool() const { return Prop != nullptr; }
 	FProperty* operator->() const { return Prop; }
@@ -22,5 +22,5 @@ struct MCPProperty
 	static TArray<MCPProperty> GetAll(UObject* Obj, EPropertyFlags Flags);
 	static TArray<MCPProperty> GetAllSubstring(UObject* Obj, EPropertyFlags Flags, const FString& Substring);
 	static TArray<MCPProperty> GetAllExactMatch(UObject* Obj, EPropertyFlags Flags, const FString& Name);
-	static MCPProperty GetOneExactMatch(UObject* Obj, EPropertyFlags Flags, const FString& Name, MCPErrorCallback Error);
+	static MCPProperty GetOneExactMatch(UObject* Obj, EPropertyFlags Flags, const FString& Name);
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Public/MCPServer.h

@@ -39,12 +39,12 @@ public:
 
 	// FTickableEditorObject
 	virtual void Tick(float DeltaTime) override;
-
-	/** Static entry point for commandlet mode (no FTickableEditorObject). */
-	static void TickServer(float DeltaTime);
 	virtual bool IsTickable() const override;
 	virtual TStatId GetStatId() const override;
 
+	/** Tick entry point for commandlet mode (no FTickableEditorObject). */
+	static void TickServer(float DeltaTime);
+
 	/** Track an object that has been modified by the current handler. */
 	static void AddTouchedObject(UObject* Obj) { GMCPServer->Notifier.AddTouchedObject(Obj); }
 

Plugins/BlueprintMCP/Source/BlueprintMCP/Public/MCPUtils.h

@@ -30,20 +30,6 @@ class UEnum;
 struct FMemberReference;
 struct FBPVariableDescription;
 
-// ----- Error callback -----
-
-struct MCPErrorCallback
-{
-	TFunction<void(const FString&)> Func;
-
-
-	MCPErrorCallback(std::nullptr_t);
-	MCPErrorCallback(FString& OutError);
-	MCPErrorCallback(FStringBuilderBase& OutResult);
-
-	void SetError(const FString& Msg) const { Func(Msg); }
-};
-
 // Stateless utility functions used by MCP handlers and the MCP server.
 // This is effectively a namespace — all methods are static.
 class MCPUtils
@@ -113,7 +99,7 @@ public:
 
 	// ----- Enum helpers -----
 	static FString EnumToString(UEnum* Enum, int64 Value, const FString& Prefix = FString());
-	static bool StringToEnum(UEnum* Enum, const FString& Str, int64& OutValue, MCPErrorCallback Error, const FString& Prefix = FString());
+	static bool StringToEnum(UEnum* Enum, const FString& Str, int64& OutValue, const FString& Prefix = FString());
 
 	template<typename T>
 	static FString EnumToString(TEnumAsByte<T> Value, const FString& Prefix = FString())
@@ -124,8 +110,8 @@ public:
 	{ return EnumToString(StaticEnum<T>(), (int64)Value, Prefix); }
 
 	template<typename T>
-	static bool StringToEnum(const FString& Str, T& OutValue, MCPErrorCallback Error, const FString& Prefix = FString())
-	{ int64 V; if (!StringToEnum(StaticEnum<T>(), Str, V, Error, Prefix)) return false; OutValue = (T)V; return true; }
+	static bool StringToEnum(const FString& Str, T& OutValue, const FString& Prefix = FString())
+	{ int64 V; if (!StringToEnum(StaticEnum<T>(), Str, V, Prefix)) return false; OutValue = (T)V; return true; }
 
 	// ----- Blueprint helpers -----
 	static TArray<UEdGraph*> AllGraphs(UBlueprint* BP);
@@ -152,7 +138,7 @@ public:
 
 	// ----- Type resolution -----
 	static UClass* FindClassByName(const FString& ClassName);
-	static bool ResolveTypeFromString(const FString& TypeName, FEdGraphPinType& OutPinType, MCPErrorCallback Error);
+	static bool ResolveTypeFromString(const FString& TypeName, FEdGraphPinType& OutPinType);
 	static FString FormatPropertyType(FProperty* Prop);
 
 	// ----- Material helpers -----
@@ -166,36 +152,29 @@ public:
 
 	// ----- Anim blueprint helpers -----
 	static UAnimationStateMachineGraph* FindStateMachineGraph(UBlueprint* BP, const FString& GraphName);
-	static UAnimStateNode* FindStateByName(UAnimationStateMachineGraph* SMGraph, const FString& StateName, MCPErrorCallback Error);
+	static UAnimStateNode* FindStateByName(UAnimationStateMachineGraph* SMGraph, const FString& StateName);
 	static UAnimStateTransitionNode* FindTransition(UAnimationStateMachineGraph* SMGraph, const FString& FromStateName, const FString& ToStateName);
 
 	// ----- Graph actions (node spawning) -----
 	static FString ActionFullName(const TSharedPtr<FEdGraphSchemaAction>& Action);
 	static TArray<TSharedPtr<FEdGraphSchemaAction>> SearchGraphActions(UEdGraph* Graph, const FString& Query, int32 MaxResults = 0, bool ExactMatch = false);
 
-	// ----- Pre/Post edit -----
-	// Call before and after modifying objects. Walks the list looking for
-	// known parent types (UMaterial, UBlueprint, etc.) and issues the
-	// appropriate notifications.
-	static void PreEdit(const TArray<UObject*>& Objects);
-	static void PostEdit(const TArray<UObject*>& Objects);
-
 	// ----- Material Parameters -----
 	static TMap<FMaterialParameterInfo, FMaterialParameterMetadata> GetMaterialParameters(UMaterialInterface* Material);
-	static bool ParseMaterialParameterAssociation(const FString& Str, EMaterialParameterAssociation& OutAssociation, MCPErrorCallback Error = nullptr);
+	static bool ParseMaterialParameterAssociation(const FString& Str, EMaterialParameterAssociation& OutAssociation);
 	static void FormatMaterialParameter(FStringBuilderBase& Result, const FMaterialParameterInfo& Info, const FMaterialParameterMetadata& Meta);
 
 	// ----- Editable template -----
 	static TArray<FProperty*> SearchProperties(UObject* Obj, const FString& Query, EPropertyFlags Flags, bool bLocal);
-	static FProperty* FindPropertyByName(UObject* Obj, const FString& Name, MCPErrorCallback Error = nullptr);
+	static FProperty* FindPropertyByName(UObject* Obj, const FString& Name);
 	static FString GetPropertyValueText(UObject* Container, FProperty* Prop);
-	static bool SetPropertyValueText(UObject* Container, FProperty* Prop, const FString& Value, MCPErrorCallback Error = nullptr);
-	static bool SetPropertyValueText(void* Container, FProperty* Prop, const FString& Value, UObject* Owner, MCPErrorCallback Error = nullptr);
+	static bool SetPropertyValueText(UObject* Container, FProperty* Prop, const FString& Value);
+	static bool SetPropertyValueText(void* Container, FProperty* Prop, const FString& Value, UObject* Owner);
 
 	// ----- JSON helpers -----
 	static FString PropertyNameToJsonKey(const FString& PropName);
-	static bool PopulateFromJson(UStruct* StructType, void* Container, const TSharedPtr<FJsonValue>& JsonValue, MCPErrorCallback Error);
-	static bool PopulateFromJson(UStruct* StructType, void* Container, const FJsonObject* Json, MCPErrorCallback Error);
+	static bool PopulateFromJson(UStruct* StructType, void* Container, const TSharedPtr<FJsonValue>& JsonValue);
+	static bool PopulateFromJson(UStruct* StructType, void* Container, const FJsonObject* Json);
 
 	// ----- Text formatting -----
 	static FString WrapText(const FString& Text, int32 ColLimit, const FString& Prefix);