Remove stringbuilder parameter for handlers

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPAssets.h"
 #include "MCPUtils.h"
@@ -37,7 +38,7 @@ public:
 		return TEXT("Create a new Animation Blueprint asset with a specified skeleton.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPPackageMaker Maker(AssetPath);
 		if (!Maker.Ok()) return;
@@ -94,14 +95,14 @@ public:
 		FKismetEditorUtilities::CompileBlueprint(NewAnimBP);
 		bool bSaved = MCPUtils::SaveBlueprintPackage(NewAnimBP);
 
-		Result.Appendf(TEXT("Created: %s\n"), *AssetPath);
+		UMCPServer::Printf(TEXT("Created: %s\n"), *AssetPath);
-		Result.Appendf(TEXT("ParentClass: %s\n"), *MCPUtils::FormatName(ParentClassObj));
+		UMCPServer::Printf(TEXT("ParentClass: %s\n"), *MCPUtils::FormatName(ParentClassObj));
-		Result.Appendf(TEXT("Saved: %s\n"), bSaved ? TEXT("true") : TEXT("false"));
+		UMCPServer::Printf(TEXT("Saved: %s\n"), bSaved ? TEXT("true") : TEXT("false"));
 
 		TArray<UEdGraph*> Graphs = MCPUtils::AllGraphs(NewAnimBP);
 		for (UEdGraph* Graph : Graphs)
 		{
-			Result.Appendf(TEXT("Graph: %s\n"), *MCPUtils::FormatName(Graph));
+			UMCPServer::Printf(TEXT("Graph: %s\n"), *MCPUtils::FormatName(Graph));
 		}
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPAssets.h"
 #include "MCPUtils.h"
@@ -27,7 +28,7 @@ public:
 		return TEXT("List all animation slot names used in an Animation Blueprint.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPAssets<UAnimBlueprint> Assets;
 		if (!Assets.Exact(Blueprint).ENone().ETwo().Load()) return;
@@ -52,12 +53,12 @@ public:
 
 		for (const FString& Slot : SlotNames)
 		{
-			Result.Appendf(TEXT("%s\n"), *Slot);
+			UMCPServer::Printf(TEXT("%s\n"), *Slot);
 		}
 
 		if (SlotNames.Num() == 0)
 		{
-			Result.Append(TEXT("No animation slot names found.\n"));
+			UMCPServer::Print(TEXT("No animation slot names found.\n"));
 		}
 	}
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/AnimBlueprint_ListSyncGroups.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
@@ -27,7 +28,7 @@ public:
 		return TEXT("List all sync group names used in an Animation Blueprint.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPFetcher F;
 		UAnimBlueprint* AnimBP = F.Walk(Path).Cast<UAnimBlueprint>();
@@ -52,13 +53,13 @@ public:
 
 		if (SyncGroupNames.Num() == 0)
 		{
-			Result.Append(TEXT("No sync groups found.\n"));
+			UMCPServer::Print(TEXT("No sync groups found.\n"));
 			return;
 		}
 
 		for (const FString& Group : SyncGroupNames)
 		{
-			Result.Appendf(TEXT("%s\n"), *Group);
+			UMCPServer::Printf(TEXT("%s\n"), *Group);
 		}
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPAssets.h"
 #include "MCPFetcher.h"
@@ -65,7 +66,7 @@ public:
 			"Replaces all existing samples.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		// Load the blend space
 		MCPAssets<UBlendSpace> Assets;
@@ -128,10 +129,10 @@ public:
 		// Save
 		bool bSaved = MCPUtils::SaveGenericPackage(BS);
 
-		Result.Appendf(TEXT("Set %d samples on %s\n"), SamplesSet, *MCPUtils::FormatName(BS));
+		UMCPServer::Printf(TEXT("Set %d samples on %s\n"), SamplesSet, *MCPUtils::FormatName(BS));
 		if (!bSaved)
 		{
-			Result.Append(TEXT("WARNING: package save failed\n"));
+			UMCPServer::Print(TEXT("WARNING: package save failed\n"));
 		}
 	}
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Asset_Backup.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPUtils.h"
 #include "Misc/Paths.h"
@@ -27,14 +28,14 @@ public:
 		return TEXT("Copy an asset's .uasset file to a .uasset.bak backup.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		FString Filename = FPaths::ConvertRelativePathToFull(
 			FPackageName::LongPackageNameToFilename(AssetPath, FPackageName::GetAssetPackageExtension()));
 
 		if (!IFileManager::Get().FileExists(*Filename))
 		{
-			Result.Appendf(TEXT("ERROR: Asset file not found: %s\n"), *Filename);
+			UMCPServer::Printf(TEXT("ERROR: Asset file not found: %s\n"), *Filename);
 			return;
 		}
 
@@ -42,10 +43,10 @@ public:
 		uint32 CopyResult = IFileManager::Get().Copy(*BackupFilename, *Filename, true);
 		if (CopyResult != COPY_OK)
 		{
-			Result.Appendf(TEXT("ERROR: Failed to copy %s to %s\n"), *Filename, *BackupFilename);
+			UMCPServer::Printf(TEXT("ERROR: Failed to copy %s to %s\n"), *Filename, *BackupFilename);
 			return;
 		}
 
-		Result.Appendf(TEXT("Backed up to %s\n"), *BackupFilename);
+		UMCPServer::Printf(TEXT("Backed up to %s\n"), *BackupFilename);
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPAssets.h"
 #include "MCPUtils.h"
@@ -34,7 +35,7 @@ public:
 			"Use force=true to skip the reference check.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		// Verify the asset file exists on disk
 		FString PackageFilename = FPackageName::LongPackageNameToFilename(
@@ -43,7 +44,7 @@ public:
 
 		if (!IFileManager::Get().FileExists(*PackageFilename))
 		{
-			Result.Appendf(TEXT("ERROR: Asset file not found on disk: %s\n"), *PackageFilename);
+			UMCPServer::Printf(TEXT("ERROR: Asset file not found on disk: %s\n"), *PackageFilename);
 			return;
 		}
 
@@ -59,22 +60,22 @@ public:
 
 		if (Referencers.Num() > 0 && !Force)
 		{
-			Result.Appendf(TEXT("ERROR: Asset is still referenced by %d package(s):\n"), Referencers.Num());
+			UMCPServer::Printf(TEXT("ERROR: Asset is still referenced by %d package(s):\n"), Referencers.Num());
 			for (const FName& Ref : Referencers)
 			{
 				FString RefStr = Ref.ToString();
 				UPackage* RefPackage = FindPackage(nullptr, *RefStr);
-				Result.Appendf(TEXT("  %s%s\n"), *RefStr,
+				UMCPServer::Printf(TEXT("  %s%s\n"), *RefStr,
 					RefPackage ? TEXT(" (loaded)") : TEXT(" (on-disk only)"));
 			}
-			Result.Append(TEXT("Use force=true to skip the reference check.\n"));
+			UMCPServer::Print(TEXT("Use force=true to skip the reference check.\n"));
 			return;
 		}
 
 		// Force delete: unload the package from memory first
 		if (Force && Referencers.Num() > 0)
 		{
-			Result.Appendf(TEXT("WARNING: Force-deleting despite %d referencer(s).\n"), Referencers.Num());
+			UMCPServer::Printf(TEXT("WARNING: Force-deleting despite %d referencer(s).\n"), Referencers.Num());
 		}
 
 		if (Force)
@@ -110,7 +111,7 @@ public:
 
 		if (!bDeleted)
 		{
-			Result.Appendf(TEXT("ERROR: Failed to delete file from disk: %s\n"), *PackageFilename);
+			UMCPServer::Printf(TEXT("ERROR: Failed to delete file from disk: %s\n"), *PackageFilename);
 			return;
 		}
 
@@ -123,6 +124,6 @@ public:
 			Registry.ScanPathsSynchronous({PackageDir}, true);
 		}
 
-		Result.Appendf(TEXT("Deleted %s\n"), *AssetPath);
+		UMCPServer::Printf(TEXT("Deleted %s\n"), *AssetPath);
 	}
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Asset_FindReferences.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPUtils.h"
 #include "AssetRegistry/AssetData.h"
@@ -26,7 +27,7 @@ public:
 		return TEXT("Find all assets that reference a given asset.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		IAssetRegistry& Registry = *IAssetRegistry::Get();
 
@@ -34,7 +35,7 @@ public:
 		FAssetData AssetData = Registry.GetAssetByObjectPath(FSoftObjectPath(AssetPath));
 		if (!AssetData.IsValid())
 		{
-			Result.Appendf(TEXT("ERROR: Asset not found: %s\n"), *AssetPath);
+			UMCPServer::Printf(TEXT("ERROR: Asset not found: %s\n"), *AssetPath);
 			return;
 		}
 
@@ -43,7 +44,7 @@ public:
 
 		if (Referencers.Num() == 0)
 		{
-			Result.Append(TEXT("No referencers found.\n"));
+			UMCPServer::Print(TEXT("No referencers found.\n"));
 			return;
 		}
 
@@ -55,13 +56,13 @@ public:
 			Registry.GetAssetsByPackageName(Ref, RefAssets);
 			if (RefAssets.Num() > 0)
 			{
-				Result.Appendf(TEXT("%s %s\n"),
+				UMCPServer::Printf(TEXT("%s %s\n"),
 					*MCPUtils::FormatName(RefAssets[0].GetClass()),
 					*RefStr);
 			}
 			else
 			{
-				Result.Appendf(TEXT("Unknown %s\n"), *RefStr);
+				UMCPServer::Printf(TEXT("Unknown %s\n"), *RefStr);
 			}
 		}
 	}

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPAssets.h"
 #include "MCPUtils.h"
@@ -30,7 +31,7 @@ public:
 		return TEXT("Rename or move an asset with reference fixup.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		// Load the asset
 		MCPAssets<UObject> Assets;
@@ -47,7 +48,7 @@ public:
 			NewAssetName = NewPath;
 			if (NewPackagePath.IsEmpty())
 			{
-				Result.Appendf(TEXT("ERROR: Cannot determine directory from AssetPath '%s'\n"), *AssetPath);
+				UMCPServer::Printf(TEXT("ERROR: Cannot determine directory from AssetPath '%s'\n"), *AssetPath);
 				return;
 			}
 		}
@@ -61,10 +62,10 @@ public:
 
 		if (!AssetTools.RenameAssets(RenameData))
 		{
-			Result.Append(TEXT("ERROR: Rename failed. The target path may be invalid or a conflicting asset may exist.\n"));
+			UMCPServer::Print(TEXT("ERROR: Rename failed. The target path may be invalid or a conflicting asset may exist.\n"));
 			return;
 		}
 
-		Result.Appendf(TEXT("Renamed to %s/%s\n"), *NewPackagePath, *NewAssetName);
+		UMCPServer::Printf(TEXT("Renamed to %s/%s\n"), *NewPackagePath, *NewAssetName);
 	}
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Asset_Restore.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPUtils.h"
 #include "Misc/PackageName.h"
@@ -28,7 +29,7 @@ public:
 		return TEXT("Restore a .uasset file from its .uasset.bak backup, reloading it in the editor.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		FString Filename = FPaths::ConvertRelativePathToFull(
 			FPackageName::LongPackageNameToFilename(AssetPath, FPackageName::GetAssetPackageExtension()));
@@ -36,7 +37,7 @@ public:
 
 		if (!IFileManager::Get().FileExists(*BackupFilename))
 		{
-			Result.Appendf(TEXT("ERROR: Backup file not found: %s\n"), *BackupFilename);
+			UMCPServer::Printf(TEXT("ERROR: Backup file not found: %s\n"), *BackupFilename);
 			return;
 		}
 
@@ -51,7 +52,7 @@ public:
 		uint32 CopyResult = IFileManager::Get().Copy(*Filename, *BackupFilename, true);
 		if (CopyResult != COPY_OK)
 		{
-			Result.Appendf(TEXT("ERROR: Failed to copy backup over %s\n"), *AssetPath);
+			UMCPServer::Printf(TEXT("ERROR: Failed to copy backup over %s\n"), *AssetPath);
 			return;
 		}
 
@@ -63,12 +64,12 @@ public:
 			UEditorLoadingAndSavingUtils::ReloadPackages({Package}, bReloaded, ErrorMessage, EReloadPackagesInteractionMode::AssumePositive);
 			if (!bReloaded)
 			{
-				Result.Appendf(TEXT("WARNING: Restored %s but reload failed: %s\n"),
+				UMCPServer::Printf(TEXT("WARNING: Restored %s but reload failed: %s\n"),
 					*AssetPath, *ErrorMessage.ToString());
 				return;
 			}
 		}
 
-		Result.Appendf(TEXT("Restored %s from backup\n"), *AssetPath);
+		UMCPServer::Printf(TEXT("Restored %s from backup\n"), *AssetPath);
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPAssets.h"
 #include "MCPUtils.h"
@@ -31,11 +32,11 @@ public:
 		return TEXT("Search for assets by name and/or type. At least one of Query or Type must be specified.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		if (Query.IsEmpty() && Type.IsEmpty())
 		{
-			Result.Append(TEXT("ERROR: At least one of Query or Type must be specified\n"));
+			UMCPServer::Print(TEXT("ERROR: At least one of Query or Type must be specified\n"));
 			return;
 		}
 
@@ -47,7 +48,7 @@ public:
 			UClass* TypeClass = MCPUtils::FindClassByName(Type);
 			if (!TypeClass)
 			{
-				Result.Appendf(TEXT("ERROR: Unknown asset type '%s'\n"), *Type);
+				UMCPServer::Printf(TEXT("ERROR: Unknown asset type '%s'\n"), *Type);
 				return;
 			}
 			Assets.NoScans().Scan(TypeClass);
@@ -63,18 +64,18 @@ public:
 		const TArray<FAssetData>& AllData = Assets.AllData();
 		for (const FAssetData& Data : AllData)
 		{
-			Result.Appendf(TEXT("%s %s\n"),
+			UMCPServer::Printf(TEXT("%s %s\n"),
 				*MCPUtils::FormatName(Data.GetClass()),
 				*Data.PackageName.ToString());
 		}
 
 		if (AllData.Num() == 0)
 		{
-			Result.Append(TEXT("No assets found.\n"));
+			UMCPServer::Print(TEXT("No assets found.\n"));
 		}
 		else if (AllData.Num() >= Limit)
 		{
-			Result.Appendf(TEXT("WARNING: You reached the limit of %d, to raise it, specify the Limit parameter.\n"), Limit);
+			UMCPServer::Printf(TEXT("WARNING: You reached the limit of %d, to raise it, specify the Limit parameter.\n"), Limit);
 		}
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPAssets.h"
 #include "MCPUtils.h"
@@ -31,7 +32,7 @@ public:
 		return TEXT("Create a new 2D Blend Space asset with a specified skeleton.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPPackageMaker Maker(AssetPath);
 		if (!Maker.Ok()) return;
@@ -46,7 +47,7 @@ public:
 		UBlendSpace* NewBS = NewObject<UBlendSpace>(Maker.Package(), FName(*Maker.Name()), RF_Public | RF_Standalone);
 		if (!NewBS)
 		{
-			Result.Append(TEXT("ERROR: Failed to create Blend Space object\n"));
+			UMCPServer::Print(TEXT("ERROR: Failed to create Blend Space object\n"));
 			return;
 		}
 
@@ -56,9 +57,9 @@ public:
 		NewBS->MarkPackageDirty();
 		bool bSaved = MCPUtils::SaveGenericPackage(NewBS);
 
-		Result.Appendf(TEXT("Created %s\n"), *NewBS->GetPathName());
+		UMCPServer::Printf(TEXT("Created %s\n"), *NewBS->GetPathName());
-		Result.Appendf(TEXT("Skeleton: %s\n"), *SkeletonObj->GetPathName());
+		UMCPServer::Printf(TEXT("Skeleton: %s\n"), *SkeletonObj->GetPathName());
 		if (!bSaved)
-			Result.Append(TEXT("WARNING: Package save failed\n"));
+			UMCPServer::Print(TEXT("WARNING: Package save failed\n"));
 	}
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/BlueprintGraph_Create.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
@@ -37,11 +38,11 @@ public:
 		return TEXT("Create a new function, macro, or custom event graph in a Blueprint.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		if (GraphType != TEXT("function") && GraphType != TEXT("macro") && GraphType != TEXT("customEvent"))
 		{
-			Result.Appendf(TEXT("ERROR: Invalid GraphType '%s'. Valid values: function, macro, customEvent\n"), *GraphType);
+			UMCPServer::Printf(TEXT("ERROR: Invalid GraphType '%s'. Valid values: function, macro, customEvent\n"), *GraphType);
 			return;
 		}
 
@@ -52,7 +53,7 @@ public:
 		// Check graph name uniqueness
 		if (!MCPUtils::AllGraphsNamed(BP, Graph).IsEmpty())
 		{
-			Result.Appendf(TEXT("ERROR: A graph named '%s' already exists in %s\n"), *Graph, *MCPUtils::FormatName(BP));
+			UMCPServer::Printf(TEXT("ERROR: A graph named '%s' already exists in %s\n"), *Graph, *MCPUtils::FormatName(BP));
 			return;
 		}
 
@@ -63,7 +64,7 @@ public:
 			{
 				if (CE->CustomFunctionName == FName(*Graph))
 				{
-					Result.Appendf(TEXT("ERROR: A custom event named '%s' already exists in %s\n"), *Graph, *MCPUtils::FormatName(BP));
+					UMCPServer::Printf(TEXT("ERROR: A custom event named '%s' already exists in %s\n"), *Graph, *MCPUtils::FormatName(BP));
 					return;
 				}
 			}
@@ -75,11 +76,11 @@ public:
 				UEdGraph::StaticClass(), UEdGraphSchema_K2::StaticClass());
 			if (!NewGraph)
 			{
-				Result.Append(TEXT("ERROR: Failed to create function graph\n"));
+				UMCPServer::Print(TEXT("ERROR: Failed to create function graph\n"));
 				return;
 			}
 			FBlueprintEditorUtils::AddFunctionGraph(BP, NewGraph, /*bIsUserCreated=*/true, /*SignatureFromObject=*/static_cast<UClass*>(nullptr));
-			Result.Appendf(TEXT("Created function graph: %s\n"), *MCPUtils::FormatName(NewGraph));
+			UMCPServer::Printf(TEXT("Created function graph: %s\n"), *MCPUtils::FormatName(NewGraph));
 		}
 		else if (GraphType == TEXT("macro"))
 		{
@@ -87,11 +88,11 @@ public:
 				UEdGraph::StaticClass(), UEdGraphSchema_K2::StaticClass());
 			if (!NewGraph)
 			{
-				Result.Append(TEXT("ERROR: Failed to create macro graph\n"));
+				UMCPServer::Print(TEXT("ERROR: Failed to create macro graph\n"));
 				return;
 			}
 			FBlueprintEditorUtils::AddMacroGraph(BP, NewGraph, /*bIsUserCreated=*/true, /*SignatureFromClass=*/nullptr);
-			Result.Appendf(TEXT("Created macro graph: %s\n"), *MCPUtils::FormatName(NewGraph));
+			UMCPServer::Printf(TEXT("Created macro graph: %s\n"), *MCPUtils::FormatName(NewGraph));
 		}
 		else // customEvent
 		{
@@ -100,7 +101,7 @@ public:
 				EventGraph = BP->UbergraphPages[0];
 			if (!EventGraph)
 			{
-				Result.Append(TEXT("ERROR: Blueprint has no EventGraph to add a custom event to\n"));
+				UMCPServer::Print(TEXT("ERROR: Blueprint has no EventGraph to add a custom event to\n"));
 				return;
 			}
 
@@ -111,7 +112,7 @@ public:
 			NewEvent->CreateNewGuid();
 			NewEvent->PostPlacedNewNode();
 			NewEvent->AllocateDefaultPins();
-			Result.Appendf(TEXT("Created custom event: %s\n"), *MCPUtils::FormatName(NewEvent));
+			UMCPServer::Printf(TEXT("Created custom event: %s\n"), *MCPUtils::FormatName(NewEvent));
 		}
 
 		MCPUtils::SaveBlueprintPackage(BP);

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/BlueprintGraph_Delete.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
@@ -31,7 +32,7 @@ public:
 		return TEXT("Delete a function or macro graph from a Blueprint. Cannot delete EventGraph pages.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPFetcher F;
 		F.Walk(Path);
@@ -73,12 +74,12 @@ public:
 			{
 				if (G && MCPUtils::Identifies(Graph, G))
 				{
-					Result.Appendf(TEXT("ERROR: Cannot delete UbergraphPage '%s'. EventGraph pages cannot be deleted.\n"),
+					UMCPServer::Printf(TEXT("ERROR: Cannot delete UbergraphPage '%s'. EventGraph pages cannot be deleted.\n"),
 						*MCPUtils::FormatName(G));
 					return;
 				}
 			}
-			Result.Appendf(TEXT("ERROR: Graph '%s' not found in blueprint %s\n"),
+			UMCPServer::Printf(TEXT("ERROR: Graph '%s' not found in blueprint %s\n"),
 				*Graph, *MCPUtils::FormatName(BP));
 			return;
 		}
@@ -88,8 +89,8 @@ public:
 		FBlueprintEditorUtils::RemoveGraph(BP, TargetGraph, EGraphRemoveFlags::Default);
 		bool bSaved = MCPUtils::SaveBlueprintPackage(BP);
 
-		Result.Appendf(TEXT("Deleted %s graph %s\n"), *GraphType, *GraphName);
+		UMCPServer::Printf(TEXT("Deleted %s graph %s\n"), *GraphType, *GraphName);
 		if (!bSaved)
-			Result.Append(TEXT("WARNING: Package save failed.\n"));
+			UMCPServer::Print(TEXT("WARNING: Package save failed.\n"));
 	}
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/BlueprintGraph_Rename.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
@@ -31,7 +32,7 @@ public:
 		return TEXT("Rename a function or macro graph in a Blueprint. Cannot rename EventGraph pages.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPFetcher F;
 		UEdGraph* TargetGraph = F.Walk(Graph).Cast<UEdGraph>();
@@ -40,14 +41,14 @@ public:
 		UBlueprint* BP = Cast<UBlueprint>(TargetGraph->GetOuter());
 		if (!BP)
 		{
-			Result.Appendf(TEXT("Error: Graph '%s' is not owned by a Blueprint.\n"), *Graph);
+			UMCPServer::Printf(TEXT("Error: Graph '%s' is not owned by a Blueprint.\n"), *Graph);
 			return;
 		}
 
 		// Check if it's an UbergraphPage -- disallow rename
 		if (BP->UbergraphPages.Contains(TargetGraph))
 		{
-			Result.Appendf(TEXT("Error: Cannot rename UbergraphPage '%s'. EventGraph pages cannot be renamed.\n"),
+			UMCPServer::Printf(TEXT("Error: Cannot rename UbergraphPage '%s'. EventGraph pages cannot be renamed.\n"),
 				*MCPUtils::FormatName(TargetGraph));
 			return;
 		}
@@ -57,7 +58,7 @@ public:
 		bool bIsMacro = BP->MacroGraphs.Contains(TargetGraph);
 		if (!bIsFunction && !bIsMacro)
 		{
-			Result.Appendf(TEXT("Error: Graph '%s' is not a function or macro graph.\n"),
+			UMCPServer::Printf(TEXT("Error: Graph '%s' is not a function or macro graph.\n"),
 				*MCPUtils::FormatName(TargetGraph));
 			return;
 		}
@@ -67,7 +68,7 @@ public:
 		{
 			if (Existing != TargetGraph)
 			{
-				Result.Appendf(TEXT("Error: A graph named '%s' already exists in '%s'.\n"),
+				UMCPServer::Printf(TEXT("Error: A graph named '%s' already exists in '%s'.\n"),
 					*NewName, *MCPUtils::FormatName(BP));
 				return;
 			}
@@ -76,7 +77,7 @@ public:
 		FBlueprintEditorUtils::RenameGraph(TargetGraph, NewName);
 		MCPUtils::SaveBlueprintPackage(BP);
 
-		Result.Appendf(TEXT("Renamed to %s %s\n"),
+		UMCPServer::Printf(TEXT("Renamed to %s %s\n"),
 			bIsFunction ? TEXT("function") : TEXT("macro"),
 			*MCPUtils::FormatName(TargetGraph));
 	}

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

@@ -40,7 +40,7 @@ public:
 			"Optionally attach it to an existing parent component.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPAssets<UBlueprint> Assets;
 		if (!Assets.Exact(Blueprint).ENone().ETwo().Load()) return;
@@ -123,13 +123,13 @@ public:
 
 		bool bSaved = MCPUtils::SaveBlueprintPackage(BP);
 
-		Result.Appendf(TEXT("Added component %s (%s)"),
+		UMCPServer::Printf(TEXT("Added component %s (%s)"),
 			*MCPUtils::FormatName(NewNode->ComponentTemplate),
 			*MCPUtils::FormatName(ComponentClassObj));
 		if (ParentSCSNode)
 		{
-			Result.Appendf(TEXT(" under %s"), *MCPUtils::FormatName(ParentSCSNode->ComponentTemplate));
+			UMCPServer::Printf(TEXT(" under %s"), *MCPUtils::FormatName(ParentSCSNode->ComponentTemplate));
 		}
-		Result.Appendf(TEXT("\nSaved: %s\n"), bSaved ? TEXT("true") : TEXT("false"));
+		UMCPServer::Printf(TEXT("\nSaved: %s\n"), bSaved ? TEXT("true") : TEXT("false"));
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
@@ -49,7 +50,7 @@ public:
 		return TEXT("Create a new multicast event dispatcher on a Blueprint, optionally with parameters.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPFetcher F;
 		UBlueprint* BP = F.Walk(Path).Cast<UBlueprint>();
@@ -62,7 +63,7 @@ public:
 		{
 			if (Var.VarName == DispatcherFName)
 			{
-				Result.Appendf(TEXT("Error: A variable or dispatcher named '%s' already exists.\n"), *DispatcherName);
+				UMCPServer::Printf(TEXT("Error: A variable or dispatcher named '%s' already exists.\n"), *DispatcherName);
 				return;
 			}
 		}
@@ -70,7 +71,7 @@ public:
 		// Check against existing graphs (functions, macros, etc.)
 		if (!MCPUtils::AllGraphsNamed(BP, DispatcherName).IsEmpty())
 		{
-			Result.Appendf(TEXT("Error: A graph named '%s' already exists.\n"), *DispatcherName);
+			UMCPServer::Printf(TEXT("Error: A graph named '%s' already exists.\n"), *DispatcherName);
 			return;
 		}
 
@@ -79,7 +80,7 @@ public:
 		DelegateType.PinCategory = UEdGraphSchema_K2::PC_MCDelegate;
 		if (!FBlueprintEditorUtils::AddMemberVariable(BP, DispatcherFName, DelegateType))
 		{
-			Result.Appendf(TEXT("Error: Failed to add delegate variable for '%s'.\n"), *DispatcherName);
+			UMCPServer::Printf(TEXT("Error: Failed to add delegate variable for '%s'.\n"), *DispatcherName);
 			return;
 		}
 
@@ -90,7 +91,7 @@ public:
 			UEdGraph::StaticClass(), UEdGraphSchema_K2::StaticClass());
 		if (!SigGraph)
 		{
-			Result.Append(TEXT("Error: Failed to create delegate signature graph.\n"));
+			UMCPServer::Print(TEXT("Error: Failed to create delegate signature graph.\n"));
 			return;
 		}
 
@@ -116,7 +117,7 @@ public:
 			if (!EntryNode)
 			{
 				MCPUtils::SaveBlueprintPackage(BP);
-				Result.Append(TEXT("Error: Event dispatcher created but entry node not found — parameters could not be added.\n"));
+				UMCPServer::Print(TEXT("Error: Event dispatcher created but entry node not found — parameters could not be added.\n"));
 				return;
 			}
 
@@ -137,9 +138,9 @@ public:
 
 		MCPUtils::SaveBlueprintPackage(BP);
 
-		Result.Appendf(TEXT("Created event dispatcher '%s'"), *DispatcherName);
+		UMCPServer::Printf(TEXT("Created event dispatcher '%s'"), *DispatcherName);
 		if (ParamCount > 0)
-			Result.Appendf(TEXT(" with %d parameter(s)"), ParamCount);
+			UMCPServer::Printf(TEXT(" with %d parameter(s)"), ParamCount);
-		Result.Append(TEXT(".\n"));
+		UMCPServer::Print(TEXT(".\n"));
 	}
 };

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

@@ -42,7 +42,7 @@ public:
 		return TEXT("Add a new parameter to a function, custom event, or event dispatcher in a Blueprint.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPAssets<UBlueprint> Assets;
 		if (!Assets.Exact(Blueprint).ENone().ETwo().Load()) return;
@@ -135,7 +135,7 @@ public:
 		EntryNode->CreateUserDefinedPin(FName(*ParamName), PinType, EGPD_Output);
 		bool bSaved = MCPUtils::SaveBlueprintPackage(BP);
 
-		Result.Appendf(TEXT("Added %s parameter '%s' to %s '%s'%s\n"),
+		UMCPServer::Printf(TEXT("Added %s parameter '%s' to %s '%s'%s\n"),
 			*ParamType, *ParamName, *NodeType, *FunctionName,
 			bSaved ? TEXT("") : TEXT(" (WARNING: save failed)"));
 	}

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

@@ -33,14 +33,14 @@ public:
 			"Creates stub function graphs for each interface function.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPAssets<UBlueprint> Assets;
 		if (!Assets.Exact(Blueprint).ENone().ETwo().Load()) return;
 		UBlueprint* BP = Assets.Object();
 
 		// Resolve the interface class
-		UClass* InterfaceClass = FindInterfaceClass(InterfaceName, Result);
+		UClass* InterfaceClass = FindInterfaceClass(InterfaceName);
 		if (!InterfaceClass) return;
 
 		// Check for duplicates
@@ -64,15 +64,15 @@ public:
 		}
 
 		// Collect stub function graph names from the newly added interface entry
-		Result.Appendf(TEXT("Added interface %s\n"), *MCPUtils::FormatName(InterfaceClass));
+		UMCPServer::Printf(TEXT("Added interface %s\n"), *MCPUtils::FormatName(InterfaceClass));
-		Result.Appendf(TEXT("Function stubs:\n"));
+		UMCPServer::Printf(TEXT("Function stubs:\n"));
 		for (const FBPInterfaceDescription& IfaceDesc : BP->ImplementedInterfaces)
 		{
 			if (IfaceDesc.Interface != InterfaceClass) continue;
 			for (const UEdGraph* Graph : IfaceDesc.Graphs)
 			{
 				if (Graph)
-					Result.Appendf(TEXT("  %s\n"), *MCPUtils::FormatName(Graph));
+					UMCPServer::Printf(TEXT("  %s\n"), *MCPUtils::FormatName(Graph));
 			}
 			break;
 		}
@@ -82,7 +82,7 @@ private:
 	// Resolve an interface name to a UClass. Tries loaded UInterface classes
 	// first (for native interfaces), then falls back to loading a Blueprint
 	// Interface asset.
-	static UClass* FindInterfaceClass(const FString& Name, FStringBuilderBase& Result)
+	static UClass* FindInterfaceClass(const FString& Name)
 	{
 		// Strategy 1: Search loaded UInterface classes by name
 		for (TObjectIterator<UClass> It; It; ++It)

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

@@ -43,7 +43,7 @@ public:
 		return TEXT("Add a new member variable to a Blueprint.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPAssets<UBlueprint> Assets;
 		if (!Assets.Exact(Blueprint).ENone().ETwo().Load()) return;
@@ -80,13 +80,13 @@ public:
 
 		bool bSaved = MCPUtils::SaveBlueprintPackage(BP);
 
-		Result.Appendf(TEXT("Added %s %s to %s\n"),
+		UMCPServer::Printf(TEXT("Added %s %s to %s\n"),
 			*VariableType, *VariableName, *MCPUtils::FormatName(BP));
 		if (IsArray)
-			Result.Append(TEXT("Container: Array\n"));
+			UMCPServer::Print(TEXT("Container: Array\n"));
 		if (!Category.IsEmpty())
-			Result.Appendf(TEXT("Category: %s\n"), *Category);
+			UMCPServer::Printf(TEXT("Category: %s\n"), *Category);
 		if (!bSaved)
-			Result.Append(TEXT("Warning: package save failed\n"));
+			UMCPServer::Print(TEXT("Warning: package save failed\n"));
 	}
 };

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

@@ -45,7 +45,7 @@ public:
 		return TEXT("Change the type of an existing parameter on a function or custom event in a Blueprint.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPAssets<UBlueprint> Assets;
 		if (!Assets.Exact(Blueprint).ENone().ETwo().Load()) return;
@@ -123,14 +123,14 @@ public:
 				for (UEdGraphPin* Linked : Pin->LinkedTo)
 				{
 					if (!Linked || !Linked->GetOwningNode()) continue;
-					Result.Appendf(TEXT("Connection at risk: %s -> %s on %s\n"),
+					UMCPServer::Printf(TEXT("Connection at risk: %s -> %s on %s\n"),
 						*MCPUtils::FormatName(Pin),
 						*MCPUtils::FormatName(Linked),
 						*MCPUtils::FormatName(Linked->GetOwningNode()));
 					AtRisk++;
 				}
 			}
-			Result.Appendf(TEXT("Dry run: %d connection(s) at risk.\n"), AtRisk);
+			UMCPServer::Printf(TEXT("Dry run: %d connection(s) at risk.\n"), AtRisk);
 			return;
 		}
 
@@ -152,7 +152,7 @@ public:
 		// Save
 		bool bSaved = MCPUtils::SaveBlueprintPackage(BP);
 
-		Result.Appendf(TEXT("Changed '%s' to %s. Save %s.\n"),
+		UMCPServer::Printf(TEXT("Changed '%s' to %s. Save %s.\n"),
 			*ParamName, *MCPUtils::FormatPinType(NewPinType),
 			bSaved ? TEXT("succeeded") : TEXT("failed"));
 	}

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPAssets.h"
@@ -43,7 +44,7 @@ public:
 			"Supports dry-run mode to preview affected nodes before committing.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPFetcher F;
 		UBlueprint* BP = F.Walk(Blueprint).Cast<UBlueprint>();
@@ -62,10 +63,10 @@ public:
 		}
 		if (!Found)
 		{
-			Result.Appendf(TEXT("ERROR: Variable '%s' not found in %s.\nAvailable variables:\n"),
+			UMCPServer::Printf(TEXT("ERROR: Variable '%s' not found in %s.\nAvailable variables:\n"),
 				*Variable, *MCPUtils::FormatName(BP));
 			for (const FBPVariableDescription& Var : BP->NewVariables)
-				Result.Appendf(TEXT("  %s\n"), *MCPUtils::FormatName(Var));
+				UMCPServer::Printf(TEXT("  %s\n"), *MCPUtils::FormatName(Var));
 			return;
 		}
 
@@ -91,14 +92,14 @@ public:
 			for (auto* VarNode : NodeArray)
 			{
 				if (VarNode->GetVarName() != VarFName) continue;
-				Result.Appendf(TEXT("  %s %s in %s\n"), NodeType,
+				UMCPServer::Printf(TEXT("  %s %s in %s\n"), NodeType,
 					*MCPUtils::FormatName(static_cast<UEdGraphNode*>(VarNode)),
 					*MCPUtils::FormatName(VarNode->GetGraph()));
 				for (UEdGraphPin* Pin : VarNode->Pins)
 				{
 					if (!Pin || Pin->LinkedTo.Num() == 0) continue;
 					if (NodeType[0] == 'G' && Pin->Direction != EGPD_Output) continue; // Get nodes: only output pins
-					Result.Appendf(TEXT("    %s connected to %d pin(s)\n"),
+					UMCPServer::Printf(TEXT("    %s connected to %d pin(s)\n"),
 						*MCPUtils::FormatName(Pin), Pin->LinkedTo.Num());
 				}
 			}
@@ -114,13 +115,13 @@ public:
 
 		if (DryRun)
 		{
-			Result.Appendf(TEXT("Dry run: would change %s from %s to %s\n"),
+			UMCPServer::Printf(TEXT("Dry run: would change %s from %s to %s\n"),
 				*MCPUtils::FormatName(*Found),
 				*MCPUtils::FormatPinType(Found->VarType),
 				*MCPUtils::FormatPinType(NewPinType));
 			if (bHasAffected)
 			{
-				Result.Append(TEXT("Affected nodes:\n"));
+				UMCPServer::Print(TEXT("Affected nodes:\n"));
 				AppendAffectedNodes(GetNodes, TEXT("Get"));
 				AppendAffectedNodes(SetNodes, TEXT("Set"));
 			}
@@ -131,14 +132,14 @@ public:
 		Found->VarType = NewPinType;
 
 		bool bSaved = MCPUtils::SaveBlueprintPackage(BP);
-		Result.Appendf(TEXT("Changed %s to %s.%s\n"),
+		UMCPServer::Printf(TEXT("Changed %s to %s.%s\n"),
 			*MCPUtils::FormatName(*Found),
 			*MCPUtils::FormatPinType(NewPinType),
 			bSaved ? TEXT("") : TEXT(" WARNING: save failed."));
 
 		if (bHasAffected)
 		{
-			Result.Append(TEXT("Affected nodes:\n"));
+			UMCPServer::Print(TEXT("Affected nodes:\n"));
 			AppendAffectedNodes(GetNodes, TEXT("Get"));
 			AppendAffectedNodes(SetNodes, TEXT("Set"));
 		}

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPAssets.h"
 #include "MCPUtils.h"
@@ -43,7 +44,7 @@ public:
 
 	// Compile a single blueprint and append results to Out.
 	// Returns true if the blueprint compiled cleanly (no errors).
-	static bool CompileAndReport(UBlueprint* BP, FStringBuilderBase& Out)
+	static bool CompileAndReport(UBlueprint* BP)
 	{
 		EBlueprintCompileOptions CompileOpts =
 			EBlueprintCompileOptions::SkipSave |
@@ -61,7 +62,7 @@ public:
 			if (!Node->bHasCompilerMessage) continue;
 			bool bIsError = (Node->ErrorType == EMessageSeverity::Error);
 			if (bIsError) ErrorCount++; else WarningCount++;
-			Out.Appendf(TEXT("  %s: [%s] %s > %s: %s\n"),
+			UMCPServer::Printf(TEXT("  %s: [%s] %s > %s: %s\n"),
 				bIsError ? TEXT("ERROR") : TEXT("WARNING"),
 				*MCPUtils::FormatName(Node->GetGraph()),
 				*MCPUtils::FormatName(Node),
@@ -74,18 +75,18 @@ public:
 
 		if (bIsValid && WarningCount == 0)
 		{
-			Out.Appendf(TEXT("  OK (status: %s)\n"), *StatusStr);
+			UMCPServer::Printf(TEXT("  OK (status: %s)\n"), *StatusStr);
 		}
 		else
 		{
-			Out.Appendf(TEXT("  status: %s, errors: %d, warnings: %d\n"),
+			UMCPServer::Printf(TEXT("  status: %s, errors: %d, warnings: %d\n"),
 				*StatusStr, ErrorCount, WarningCount);
 		}
 
 		return bIsValid;
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPAssets<UBlueprint> Finder;
 		Finder.Scan<UBlueprint>().Scan<UWorld>();
@@ -104,7 +105,7 @@ public:
 		// countOnly: return count without compiling anything
 		if (CountOnly)
 		{
-			Result.Appendf(TEXT("Matching blueprints: %d\n"), TotalMatching);
+			UMCPServer::Printf(TEXT("Matching blueprints: %d\n"), TotalMatching);
 			return;
 		}
 
@@ -131,12 +132,12 @@ public:
 			UBlueprint* BP = Loader.Object();
 
 			TotalChecked++;
-			Result.Appendf(TEXT("%s:\n"), *MCPUtils::FormatName(BP));
+			UMCPServer::Printf(TEXT("%s:\n"), *MCPUtils::FormatName(BP));
-			bool bValid = CompileAndReport(BP, Result);
+			bool bValid = CompileAndReport(BP);
 			if (bValid) TotalPassed++; else TotalFailed++;
 		}
 
-		Result.Appendf(TEXT("\nSummary: %d checked, %d passed, %d failed (of %d matching)\n"),
+		UMCPServer::Printf(TEXT("\nSummary: %d checked, %d passed, %d failed (of %d matching)\n"),
 			TotalChecked, TotalPassed, TotalFailed, TotalMatching);
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPAssets.h"
 #include "MCPUtils.h"
@@ -34,7 +35,7 @@ public:
 		return TEXT("Create a new Blueprint asset with a specified parent class and type.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPPackageMaker Maker(AssetPath);
 		if (!Maker.Ok()) return;
@@ -93,11 +94,11 @@ public:
 		bool bSaved = MCPUtils::SaveBlueprintPackage(NewBP);
 
 		// Report result
-		Result.Appendf(TEXT("Created: %s\n"), *MCPUtils::FormatName(NewBP));
+		UMCPServer::Printf(TEXT("Created: %s\n"), *MCPUtils::FormatName(NewBP));
-		Result.Appendf(TEXT("Parent: %s\n"), *MCPUtils::FormatName(ParentClassObj));
+		UMCPServer::Printf(TEXT("Parent: %s\n"), *MCPUtils::FormatName(ParentClassObj));
 		if (!bSaved)
-			Result.Append(TEXT("Warning: save failed\n"));
+			UMCPServer::Print(TEXT("Warning: save failed\n"));
 		for (UEdGraph* Graph : MCPUtils::AllGraphs(NewBP))
-			Result.Appendf(TEXT("Graph: %s\n"), *MCPUtils::FormatName(Graph));
+			UMCPServer::Printf(TEXT("Graph: %s\n"), *MCPUtils::FormatName(Graph));
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPAssets.h"
 #include "MCPUtils.h"
@@ -37,7 +38,7 @@ public:
 			"finding divergence after copy-paste, or auditing consistency.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		// Load both blueprints
 		MCPAssets<UBlueprint> AssetsA;
@@ -89,13 +90,13 @@ public:
 
 			if (!pGA)
 			{
-				Result.Appendf(TEXT("Graph %s: only in B (%d nodes)\n"), *GraphName, (*pGB)->Nodes.Num());
+				UMCPServer::Printf(TEXT("Graph %s: only in B (%d nodes)\n"), *GraphName, (*pGB)->Nodes.Num());
 				TotalDiffs++;
 				continue;
 			}
 			if (!pGB)
 			{
-				Result.Appendf(TEXT("Graph %s: only in A (%d nodes)\n"), *GraphName, (*pGA)->Nodes.Num());
+				UMCPServer::Printf(TEXT("Graph %s: only in A (%d nodes)\n"), *GraphName, (*pGA)->Nodes.Num());
 				TotalDiffs++;
 				continue;
 			}
@@ -181,32 +182,32 @@ public:
 
 			if (bIdentical)
 			{
-				Result.Appendf(TEXT("Graph %s: identical (%d nodes)\n"), *GraphName, GA->Nodes.Num());
+				UMCPServer::Printf(TEXT("Graph %s: identical (%d nodes)\n"), *GraphName, GA->Nodes.Num());
 				continue;
 			}
 
 			TotalDiffs++;
-			Result.Appendf(TEXT("Graph %s: different (A=%d nodes, B=%d nodes)\n"), *GraphName, GA->Nodes.Num(), GB->Nodes.Num());
+			UMCPServer::Printf(TEXT("Graph %s: different (A=%d nodes, B=%d nodes)\n"), *GraphName, GA->Nodes.Num(), GB->Nodes.Num());
 
 			if (!OnlyInA.IsEmpty())
 			{
-				Result.Append(TEXT("  Nodes only in A:\n"));
+				UMCPServer::Print(TEXT("  Nodes only in A:\n"));
-				for (const FString& Line : OnlyInA) Result.Appendf(TEXT("  %s\n"), *Line);
+				for (const FString& Line : OnlyInA) UMCPServer::Printf(TEXT("  %s\n"), *Line);
 			}
 			if (!OnlyInB.IsEmpty())
 			{
-				Result.Append(TEXT("  Nodes only in B:\n"));
+				UMCPServer::Print(TEXT("  Nodes only in B:\n"));
-				for (const FString& Line : OnlyInB) Result.Appendf(TEXT("  %s\n"), *Line);
+				for (const FString& Line : OnlyInB) UMCPServer::Printf(TEXT("  %s\n"), *Line);
 			}
 			if (!ConnsOnlyInA.IsEmpty())
 			{
-				Result.Append(TEXT("  Connections only in A:\n"));
+				UMCPServer::Print(TEXT("  Connections only in A:\n"));
-				for (const FString& Line : ConnsOnlyInA) Result.Appendf(TEXT("  %s\n"), *Line);
+				for (const FString& Line : ConnsOnlyInA) UMCPServer::Printf(TEXT("  %s\n"), *Line);
 			}
 			if (!ConnsOnlyInB.IsEmpty())
 			{
-				Result.Append(TEXT("  Connections only in B:\n"));
+				UMCPServer::Print(TEXT("  Connections only in B:\n"));
-				for (const FString& Line : ConnsOnlyInB) Result.Appendf(TEXT("  %s\n"), *Line);
+				for (const FString& Line : ConnsOnlyInB) UMCPServer::Printf(TEXT("  %s\n"), *Line);
 			}
 		}
 
@@ -225,17 +226,17 @@ public:
 
 		if (!VarsOnlyInA.IsEmpty())
 		{
-			Result.Append(TEXT("Variables only in A:\n"));
+			UMCPServer::Print(TEXT("Variables only in A:\n"));
-			for (const FString& Name : VarsOnlyInA) Result.Appendf(TEXT("  %s\n"), *Name);
+			for (const FString& Name : VarsOnlyInA) UMCPServer::Printf(TEXT("  %s\n"), *Name);
 			TotalDiffs += VarsOnlyInA.Num();
 		}
 		if (!VarsOnlyInB.IsEmpty())
 		{
-			Result.Append(TEXT("Variables only in B:\n"));
+			UMCPServer::Print(TEXT("Variables only in B:\n"));
-			for (const FString& Name : VarsOnlyInB) Result.Appendf(TEXT("  %s\n"), *Name);
+			for (const FString& Name : VarsOnlyInB) UMCPServer::Printf(TEXT("  %s\n"), *Name);
 			TotalDiffs += VarsOnlyInB.Num();
 		}
 
-		Result.Appendf(TEXT("Total differences: %d\n"), TotalDiffs);
+		UMCPServer::Printf(TEXT("Total differences: %d\n"), TotalDiffs);
 	}
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Blueprint_Dump.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
@@ -31,46 +32,46 @@ public:
 			"and graph names. Does not include graph contents (use DumpGraphs for that).");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPFetcher F;
 		UBlueprint* BP = F.Walk(Blueprint).Cast<UBlueprint>();
 		if (!BP) return;
 
 		// Header
-		Result.Appendf(TEXT("Blueprint: %s\n"), *MCPUtils::FormatName(BP));
+		UMCPServer::Printf(TEXT("Blueprint: %s\n"), *MCPUtils::FormatName(BP));
-		Result.Appendf(TEXT("Parent: %s\n"), BP->ParentClass ? *MCPUtils::FormatName(BP->ParentClass) : TEXT("None"));
+		UMCPServer::Printf(TEXT("Parent: %s\n"), BP->ParentClass ? *MCPUtils::FormatName(BP->ParentClass) : TEXT("None"));
-		Result.Appendf(TEXT("Type: %s\n"),
+		UMCPServer::Printf(TEXT("Type: %s\n"),
 			*MCPUtils::EnumToString(BP->BlueprintType));
 
 		// Animation Blueprint
 		if (UAnimBlueprint* AnimBP = Cast<UAnimBlueprint>(BP))
 		{
 			if (AnimBP->TargetSkeleton)
-				Result.Appendf(TEXT("TargetSkeleton: %s\n"), *AnimBP->TargetSkeleton->GetPathName());
+				UMCPServer::Printf(TEXT("TargetSkeleton: %s\n"), *AnimBP->TargetSkeleton->GetPathName());
 		}
 
 		// Interfaces
 		for (const FBPInterfaceDescription& I : BP->ImplementedInterfaces)
 		{
 			if (I.Interface)
-				Result.Appendf(TEXT("Interface: %s\n"), *MCPUtils::FormatName(I.Interface));
+				UMCPServer::Printf(TEXT("Interface: %s\n"), *MCPUtils::FormatName(I.Interface));
 		}
 
 		// Variables
 		if (!BP->NewVariables.IsEmpty())
 		{
-			Result.Append(TEXT("\nVariables:\n"));
+			UMCPServer::Print(TEXT("\nVariables:\n"));
 			for (const FBPVariableDescription& V : BP->NewVariables)
 			{
-				Result.Appendf(TEXT("  %s %s"),
+				UMCPServer::Printf(TEXT("  %s %s"),
 					*MCPUtils::FormatPinType(V.VarType),
 					*MCPUtils::FormatName(V));
 				if (!V.DefaultValue.IsEmpty())
-					Result.Appendf(TEXT(" = %s"), *V.DefaultValue);
+					UMCPServer::Printf(TEXT(" = %s"), *V.DefaultValue);
 				if (!V.Category.IsEmpty() && V.Category.ToString() != TEXT("Default"))
-					Result.Appendf(TEXT("  [%s]"), *V.Category.ToString());
+					UMCPServer::Printf(TEXT("  [%s]"), *V.Category.ToString());
-				Result.Append(TEXT("\n"));
+				UMCPServer::Print(TEXT("\n"));
 			}
 		}
 
@@ -80,16 +81,16 @@ public:
 			const TArray<USCS_Node*>& AllNodes = SCS->GetAllNodes();
 			if (!AllNodes.IsEmpty())
 			{
-				Result.Append(TEXT("\nComponents:\n"));
+				UMCPServer::Print(TEXT("\nComponents:\n"));
 				for (USCS_Node* Node : AllNodes)
 				{
 					if (!Node || !Node->ComponentTemplate) continue;
-					Result.Appendf(TEXT("  %s (%s)"),
+					UMCPServer::Printf(TEXT("  %s (%s)"),
 						*MCPUtils::FormatName(Node->ComponentTemplate),
 						*MCPUtils::FormatName(Node->ComponentClass));
 					if (Node->ParentComponentOrVariableName != NAME_None)
-						Result.Appendf(TEXT("  parent=%s"), *Node->ParentComponentOrVariableName.ToString());
+						UMCPServer::Printf(TEXT("  parent=%s"), *Node->ParentComponentOrVariableName.ToString());
-					Result.Append(TEXT("\n"));
+					UMCPServer::Print(TEXT("\n"));
 				}
 			}
 		}
@@ -98,9 +99,9 @@ public:
 		TArray<UEdGraph*> Graphs = MCPUtils::AllGraphs(BP);
 		if (!Graphs.IsEmpty())
 		{
-			Result.Append(TEXT("\nGraphs:\n"));
+			UMCPServer::Print(TEXT("\nGraphs:\n"));
 			for (UEdGraph* Graph : Graphs)
-				Result.Appendf(TEXT("  %s\n"), *MCPUtils::FormatName(Graph));
+				UMCPServer::Printf(TEXT("  %s\n"), *MCPUtils::FormatName(Graph));
 		}
 	}
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Blueprint_ListComponents.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
@@ -29,7 +30,7 @@ public:
 			"showing hierarchy and component classes.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPFetcher F;
 		F.Walk(Path);
@@ -41,7 +42,7 @@ public:
 		USimpleConstructionScript* SCS = BP->SimpleConstructionScript;
 		if (!SCS)
 		{
-			Result.Append(TEXT("ERROR: Not an Actor Blueprint (no SimpleConstructionScript)\n"));
+			UMCPServer::Print(TEXT("ERROR: Not an Actor Blueprint (no SimpleConstructionScript)\n"));
 			return;
 		}
 
@@ -50,11 +51,11 @@ public:
 
 		if (AllNodes.Num() == 0)
 		{
-			Result.Append(TEXT("No components.\n"));
+			UMCPServer::Print(TEXT("No components.\n"));
 			return;
 		}
 
-		Result.Append(TEXT("WARNING: This only lists components added in this blueprint's SCS. "
+		UMCPServer::Print(TEXT("WARNING: This only lists components added in this blueprint's SCS. "
 			"It does not include inherited components from C++ parent classes "
 			"(available via the CDO's OwnedComponents) or from parent blueprint SCS nodes.\n"));
 
@@ -62,34 +63,34 @@ public:
 		for (USCS_Node* Root : RootNodes)
 		{
 			if (!Root) continue;
-			EmitNode(Root, 0, Root == RootNodes[0], Result);
+			EmitNode(Root, 0, Root == RootNodes[0]);
 		}
 	}
 
 private:
-	void EmitNode(USCS_Node* Node, int32 Depth, bool bIsSceneRoot, FStringBuilderBase& Result)
+	void EmitNode(USCS_Node* Node, int32 Depth, bool bIsSceneRoot)
 	{
 		// Indent to show hierarchy
 		for (int32 i = 0; i < Depth; i++)
-			Result.Append(TEXT("  "));
+			UMCPServer::Print(TEXT("  "));
 
 		FString ClassName = Node->ComponentClass
 			? MCPUtils::FormatName(Node->ComponentClass)
 			: TEXT("None");
 
-		Result.Appendf(TEXT("%s %s"),
+		UMCPServer::Printf(TEXT("%s %s"),
 			*ClassName,
 			*MCPUtils::FormatName(Node->ComponentTemplate));
 
 		if (bIsSceneRoot && Depth == 0)
-			Result.Append(TEXT(" [SceneRoot]"));
+			UMCPServer::Print(TEXT(" [SceneRoot]"));
 
-		Result.Append(TEXT("\n"));
+		UMCPServer::Print(TEXT("\n"));
 
 		for (USCS_Node* Child : Node->GetChildNodes())
 		{
 			if (!Child) continue;
-			EmitNode(Child, Depth + 1, false, Result);
+			EmitNode(Child, Depth + 1, false);
 		}
 	}
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Blueprint_ListEventDispatchers.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
@@ -31,7 +32,7 @@ public:
 		return TEXT("List all event dispatchers on a Blueprint, including their parameter signatures.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPFetcher F;
 		UBlueprint* BP = F.Walk(Path).Cast<UBlueprint>();
@@ -42,7 +43,7 @@ public:
 
 		for (const FName& DelegateName : DelegateNameSet)
 		{
-			Result.Appendf(TEXT("%s("), *DelegateName.ToString());
+			UMCPServer::Printf(TEXT("%s("), *DelegateName.ToString());
 
 			UEdGraph* SigGraph = FBlueprintEditorUtils::GetDelegateSignatureGraphByName(BP, DelegateName);
 			if (SigGraph)
@@ -53,9 +54,9 @@ public:
 					for (const TSharedPtr<FUserPinInfo>& PinInfo : FE->UserDefinedPins)
 					{
 						if (!PinInfo.IsValid()) continue;
-						if (!bFirst) Result.Append(TEXT(", "));
+						if (!bFirst) UMCPServer::Print(TEXT(", "));
 						bFirst = false;
-						Result.Appendf(TEXT("%s %s"),
+						UMCPServer::Printf(TEXT("%s %s"),
 							*MCPUtils::FormatPinType(PinInfo->PinType),
 							*PinInfo->PinName.ToString());
 					}
@@ -63,12 +64,12 @@ public:
 				}
 			}
 
-			Result.Append(TEXT(")\n"));
+			UMCPServer::Print(TEXT(")\n"));
 		}
 
 		if (DelegateNameSet.Num() == 0)
 		{
-			Result.Append(TEXT("No event dispatchers found.\n"));
+			UMCPServer::Print(TEXT("No event dispatchers found.\n"));
 		}
 	}
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Blueprint_ListInterfaces.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
@@ -27,7 +28,7 @@ public:
 			"including their function graphs.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPFetcher F;
 		F.Walk(Path);
@@ -41,17 +42,17 @@ public:
 			if (!IfaceDesc.Interface) continue;
 			bAny = true;
 
-			Result.Appendf(TEXT("Interface: %s\n"), *MCPUtils::FormatName(IfaceDesc.Interface));
+			UMCPServer::Printf(TEXT("Interface: %s\n"), *MCPUtils::FormatName(IfaceDesc.Interface));
 			for (const UEdGraph* Graph : IfaceDesc.Graphs)
 			{
 				if (!Graph) continue;
-				Result.Appendf(TEXT("  %s\n"), *MCPUtils::FormatName(Graph));
+				UMCPServer::Printf(TEXT("  %s\n"), *MCPUtils::FormatName(Graph));
 			}
 		}
 
 		if (!bAny)
 		{
-			Result.Append(TEXT("No interfaces implemented.\n"));
+			UMCPServer::Print(TEXT("No interfaces implemented.\n"));
 		}
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPAssets.h"
 #include "MCPUtils.h"
@@ -31,7 +32,7 @@ public:
 			"Reports compiler warnings and errors.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		// Load Blueprint
 		MCPAssets<UBlueprint> Assets;
@@ -61,24 +62,24 @@ public:
 		}
 
 		// Summary
-		Result.Appendf(TEXT("Refreshed %s: %d graphs, %d nodes"), *MCPUtils::FormatName(BP), GraphCount, NodeCount);
+		UMCPServer::Printf(TEXT("Refreshed %s: %d graphs, %d nodes"), *MCPUtils::FormatName(BP), GraphCount, NodeCount);
 		if (OrphanedPinsRemoved > 0)
 		{
-			Result.Appendf(TEXT(", %d orphaned pins removed"), OrphanedPinsRemoved);
+			UMCPServer::Printf(TEXT(", %d orphaned pins removed"), OrphanedPinsRemoved);
 		}
-		Result.Append(TEXT("\n"));
+		UMCPServer::Print(TEXT("\n"));
 
 		// Collect compiler warnings and errors
 		if (BP->Status == BS_Error)
 		{
-			Result.Append(TEXT("ERROR: Blueprint has compiler errors after refresh\n"));
+			UMCPServer::Print(TEXT("ERROR: Blueprint has compiler errors after refresh\n"));
 		}
 
 		for (UEdGraphNode* Node : MCPUtils::AllNodes(BP))
 		{
 			if (!Node->bHasCompilerMessage) continue;
 			const TCHAR* Prefix = (Node->ErrorType == EMessageSeverity::Error) ? TEXT("ERROR") : TEXT("WARNING");
-			Result.Appendf(TEXT("%s: [%s] %s: %s\n"),
+			UMCPServer::Printf(TEXT("%s: [%s] %s: %s\n"),
 				Prefix, *MCPUtils::FormatName(Node->GetGraph()),
 				*MCPUtils::FormatName(Node), *Node->ErrorMsg);
 		}

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Blueprint_RemoveComponent.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
@@ -31,7 +32,7 @@ public:
 		return TEXT("Remove a component from a Blueprint's SimpleConstructionScript.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPFetcher F;
 		UBlueprint* BP = F.Walk(Blueprint).Cast<UBlueprint>();
@@ -40,7 +41,7 @@ public:
 		USimpleConstructionScript* SCS = BP->SimpleConstructionScript;
 		if (!SCS)
 		{
-			Result.Append(TEXT("ERROR: Not an Actor Blueprint (no SimpleConstructionScript).\n"));
+			UMCPServer::Print(TEXT("ERROR: Not an Actor Blueprint (no SimpleConstructionScript).\n"));
 			return;
 		}
 
@@ -59,12 +60,12 @@ public:
 
 		if (!NodeToRemove)
 		{
-			Result.Appendf(TEXT("ERROR: Component '%s' not found.\nAvailable components:\n"),
+			UMCPServer::Printf(TEXT("ERROR: Component '%s' not found.\nAvailable components:\n"),
 				*Component);
 			for (USCS_Node* Node : AllNodes)
 			{
 				if (Node && Node->ComponentTemplate)
-					Result.Appendf(TEXT("  %s\n"), *MCPUtils::FormatName(Node->ComponentTemplate));
+					UMCPServer::Printf(TEXT("  %s\n"), *MCPUtils::FormatName(Node->ComponentTemplate));
 			}
 			return;
 		}
@@ -73,7 +74,7 @@ public:
 		const TArray<USCS_Node*>& RootNodes = SCS->GetRootNodes();
 		if (RootNodes.Contains(NodeToRemove) && NodeToRemove->GetChildNodes().Num() > 0)
 		{
-			Result.Appendf(TEXT("ERROR: Cannot remove '%s' — it is a root component with %d child(ren). "
+			UMCPServer::Printf(TEXT("ERROR: Cannot remove '%s' — it is a root component with %d child(ren). "
 				"Remove or re-parent the children first.\n"),
 				*MCPUtils::FormatName(NodeToRemove->ComponentTemplate),
 				NodeToRemove->GetChildNodes().Num());
@@ -87,7 +88,7 @@ public:
 
 		bool bSaved = MCPUtils::SaveBlueprintPackage(BP);
 
-		Result.Appendf(TEXT("Removed component %s.%s\n"),
+		UMCPServer::Printf(TEXT("Removed component %s.%s\n"),
 			*RemovedName,
 			bSaved ? TEXT("") : TEXT(" WARNING: save failed."));
 	}

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPAssets.h"
@@ -36,7 +37,7 @@ public:
 		return TEXT("Remove a parameter from a function or custom event in a Blueprint.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPAssets<UBlueprint> Assets;
 		if (!Assets.Exact(Blueprint).ENone().ETwo().Load()) return;
@@ -68,11 +69,11 @@ public:
 
 		if (!EntryNode)
 		{
-			Result.Appendf(TEXT("Error: Function or event '%s' not found.\nAvailable:\n"), *FunctionName);
+			UMCPServer::Printf(TEXT("Error: Function or event '%s' not found.\nAvailable:\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(CE));
+				UMCPServer::Printf(TEXT("  event: %s\n"), *MCPUtils::FormatName(CE));
 			return;
 		}
 
@@ -90,11 +91,11 @@ public:
 
 		if (RemovedIndex == INDEX_NONE)
 		{
-			Result.Appendf(TEXT("Error: Parameter '%s' not found on %s.\nAvailable:\n"),
+			UMCPServer::Printf(TEXT("Error: Parameter '%s' not found on %s.\nAvailable:\n"),
 				*ParamName, *MCPUtils::FormatName(EntryNode));
 			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;
 		}
 
@@ -108,8 +109,8 @@ public:
 
 		bool bSaved = MCPUtils::SaveBlueprintPackage(BP);
 
-		Result.Appendf(TEXT("Removed parameter '%s' from %s.\n"), *ParamName, *MCPUtils::FormatName(EntryNode));
+		UMCPServer::Printf(TEXT("Removed parameter '%s' from %s.\n"), *ParamName, *MCPUtils::FormatName(EntryNode));
 		if (!bSaved)
-			Result.Append(TEXT("Warning: save failed.\n"));
+			UMCPServer::Print(TEXT("Warning: save failed.\n"));
 	}
 };

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

@@ -35,7 +35,7 @@ public:
 			"Optionally preserve the function graphs as regular functions.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPAssets<UBlueprint> Assets;
 		if (!Assets.Exact(Blueprint).ENone().ETwo().Load()) return;
@@ -67,8 +67,8 @@ public:
 		FTopLevelAssetPath InterfacePath = FoundInterface->GetClassPathName();
 		FBlueprintEditorUtils::RemoveInterface(BP, InterfacePath, PreserveFunctions);
 
-		Result.Appendf(TEXT("Removed interface %s\n"), *MCPUtils::FormatName(FoundInterface));
+		UMCPServer::Printf(TEXT("Removed interface %s\n"), *MCPUtils::FormatName(FoundInterface));
 		if (PreserveFunctions)
-			Result.Append(TEXT("Function graphs preserved as regular functions.\n"));
+			UMCPServer::Print(TEXT("Function graphs preserved as regular functions.\n"));
 	}
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Blueprint_RemoveVariable.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
@@ -30,7 +31,7 @@ public:
 		return TEXT("Remove a member variable from a Blueprint.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPFetcher F;
 		UBlueprint* BP = F.Walk(Blueprint).Cast<UBlueprint>();
@@ -50,11 +51,11 @@ public:
 
 		if (!Found)
 		{
-			Result.Appendf(TEXT("ERROR: Variable '%s' not found in %s.\nAvailable variables:\n"),
+			UMCPServer::Printf(TEXT("ERROR: Variable '%s' not found in %s.\nAvailable variables:\n"),
 				*VariableName, *MCPUtils::FormatName(BP));
 			for (const FBPVariableDescription& Var : BP->NewVariables)
 			{
-				Result.Appendf(TEXT("  %s\n"), *MCPUtils::FormatName(Var));
+				UMCPServer::Printf(TEXT("  %s\n"), *MCPUtils::FormatName(Var));
 			}
 			return;
 		}
@@ -65,7 +66,7 @@ public:
 		FBlueprintEditorUtils::RemoveMemberVariable(BP, VarFName);
 
 		bool bSaved = MCPUtils::SaveBlueprintPackage(BP);
-		Result.Appendf(TEXT("Removed variable %s from %s.%s\n"),
+		UMCPServer::Printf(TEXT("Removed variable %s from %s.%s\n"),
 			*VarFName.ToString(), *MCPUtils::FormatName(BP),
 			bSaved ? TEXT("") : TEXT(" WARNING: save failed."));
 	}

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

@@ -33,7 +33,7 @@ public:
 		return TEXT("Change a Blueprint's parent class. Accepts C++ class names or Blueprint names.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		// Load Blueprint
 		MCPAssets<UBlueprint> Assets;
@@ -66,9 +66,9 @@ public:
 		FKismetEditorUtilities::CompileBlueprint(BP);
 		bool bSaved = MCPUtils::SaveBlueprintPackage(BP);
 
-		Result.Appendf(TEXT("Reparented %s: %s -> %s\n"),
+		UMCPServer::Printf(TEXT("Reparented %s: %s -> %s\n"),
 			*MCPUtils::FormatName(BP), *OldParentName, *MCPUtils::FormatName(NewParentClassObj));
 		if (!bSaved)
-			Result.Append(TEXT("Warning: save failed\n"));
+			UMCPServer::Print(TEXT("Warning: save failed\n"));
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPAssets.h"
 #include "MCPUtils.h"
@@ -36,7 +37,7 @@ public:
 		return TEXT("List all Blueprint assets in the project, with optional filtering by name, parent class, or type.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPAssets<UObject> Assets;
 		Assets.NoScans().Substring(Query).Limit(500);
@@ -73,13 +74,13 @@ public:
 				}
 			}
 
-			Result.Appendf(TEXT("%30s %s\n"), *ParentClassName, *Asset.PackageName.ToString());
+			UMCPServer::Printf(TEXT("%30s %s\n"), *ParentClassName, *Asset.PackageName.ToString());
 			Count++;
 		}
 
 		if (Count == 0)
 		{
-			Result.Append(TEXT("No blueprint assets found.\n"));
+			UMCPServer::Print(TEXT("No blueprint assets found.\n"));
 		}
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPAssets.h"
 #include "MCPUtils.h"
@@ -41,7 +42,7 @@ public:
 		return TEXT("Search across all Blueprint graphs for nodes matching a query string.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		int32 Limit = (MaxResults > 0) ? FMath::Clamp(MaxResults, 1, 200) : 50;
 		int32 Count = 0;
@@ -85,15 +86,15 @@ public:
 				if (!bMatch) continue;
 
 				Count++;
-				Result.Appendf(TEXT("blueprint: %s\n"), *MCPUtils::FormatName(BP));
+				UMCPServer::Printf(TEXT("blueprint: %s\n"), *MCPUtils::FormatName(BP));
-				Result.Appendf(TEXT("  graph: %s\n"), *MCPUtils::FormatName(Node->GetGraph()));
+				UMCPServer::Printf(TEXT("  graph: %s\n"), *MCPUtils::FormatName(Node->GetGraph()));
-				Result.Appendf(TEXT("  node: %s\n"), *MCPUtils::FormatName(Node));
+				UMCPServer::Printf(TEXT("  node: %s\n"), *MCPUtils::FormatName(Node));
-				Result.Appendf(TEXT("  class: %s\n"), *MCPUtils::FormatName(Node->GetClass()));
+				UMCPServer::Printf(TEXT("  class: %s\n"), *MCPUtils::FormatName(Node->GetClass()));
-				if (!FuncName.IsEmpty()) Result.Appendf(TEXT("  function: %s\n"), *FuncName);
+				if (!FuncName.IsEmpty()) UMCPServer::Printf(TEXT("  function: %s\n"), *FuncName);
-				if (!EventName.IsEmpty()) Result.Appendf(TEXT("  event: %s\n"), *EventName);
+				if (!EventName.IsEmpty()) UMCPServer::Printf(TEXT("  event: %s\n"), *EventName);
-				if (!VarName.IsEmpty()) Result.Appendf(TEXT("  variable: %s\n"), *VarName);
+				if (!VarName.IsEmpty()) UMCPServer::Printf(TEXT("  variable: %s\n"), *VarName);
-				if (bIsLevelBP) Result.Append(TEXT("  level-blueprint: true\n"));
+				if (bIsLevelBP) UMCPServer::Print(TEXT("  level-blueprint: true\n"));
-				Result.Append(TEXT("\n"));
+				UMCPServer::Print(TEXT("\n"));
 			}
 		};
 
@@ -120,7 +121,7 @@ public:
 			SearchBlueprint(LevelBP, true);
 		}
 
-		Result.Appendf(TEXT("Results: %d\n"), Count);
+		UMCPServer::Printf(TEXT("Results: %d\n"), Count);
-		if (Count >= Limit) Result.Appendf(TEXT("(limit %d reached, use MaxResults to increase)\n"), Limit);
+		if (Count >= Limit) UMCPServer::Printf(TEXT("(limit %d reached, use MaxResults to increase)\n"), Limit);
 	}
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Class_Search.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPUtils.h"
 #include "UObject/UObjectIterator.h"
@@ -36,7 +37,7 @@ public:
 			"Returns class names, parent class, package, and flags.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		Limit = FMath::Clamp(Limit, 1, 500);
 
@@ -53,7 +54,7 @@ public:
 			}
 			if (!ParentClassObj)
 			{
-				Result.Appendf(TEXT("Error: Parent class '%s' not found\n"), *ParentClass);
+				UMCPServer::Printf(TEXT("Error: Parent class '%s' not found\n"), *ParentClass);
 				return;
 			}
 		}
@@ -78,16 +79,16 @@ public:
 			}
 		}
 
-		Result.Appendf(TEXT("Found %d classes"), TotalMatched);
+		UMCPServer::Printf(TEXT("Found %d classes"), TotalMatched);
 		if (TotalMatched > Limit)
 		{
-			Result.Appendf(TEXT(" (showing %d)"), Limit);
+			UMCPServer::Printf(TEXT(" (showing %d)"), Limit);
 		}
-		Result.Append(TEXT("\n"));
+		UMCPServer::Print(TEXT("\n"));
 
 		for (UClass* Class : Matches)
 		{
-			Result.Appendf(TEXT("  %s"), *MCPUtils::FormatName(Class));
+			UMCPServer::Printf(TEXT("  %s"), *MCPUtils::FormatName(Class));
 
 			// Flags
 			TStringBuilder<64> Flags;
@@ -97,15 +98,15 @@ public:
 			if (Class->ClassGeneratedBy) Flags.Append(TEXT(" Blueprint"));
 			if (Flags.Len() > 0)
 			{
-				Result.Appendf(TEXT(" [%s]"), Flags.ToString() + 1); // skip leading space
+				UMCPServer::Printf(TEXT(" [%s]"), Flags.ToString() + 1); // skip leading space
 			}
 
 			if (Class->GetSuperClass())
 			{
-				Result.Appendf(TEXT(" : %s"), *MCPUtils::FormatName(Class->GetSuperClass()));
+				UMCPServer::Printf(TEXT(" : %s"), *MCPUtils::FormatName(Class->GetSuperClass()));
 			}
 
-			Result.Append(TEXT("\n"));
+			UMCPServer::Print(TEXT("\n"));
 		}
 	}
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Class_ShowProperties.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPUtils.h"
 #include "Class_ShowProperties.generated.h"
@@ -27,16 +28,16 @@ public:
 		return TEXT("List properties on a UClass, including type, owning class, and property flags.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		UClass* FoundClass = MCPUtils::FindClassByName(ClassName);
 		if (!FoundClass)
 		{
-			Result.Appendf(TEXT("ERROR: Class '%s' not found\n"), *ClassName);
+			UMCPServer::Printf(TEXT("ERROR: Class '%s' not found\n"), *ClassName);
 			return;
 		}
 
-		Result.Appendf(TEXT("Properties of %s:\n"), *MCPUtils::FormatName(FoundClass));
+		UMCPServer::Printf(TEXT("Properties of %s:\n"), *MCPUtils::FormatName(FoundClass));
 
 		int32 Count = 0;
 		for (TFieldIterator<FProperty> PropIt(FoundClass); PropIt; ++PropIt)
@@ -61,18 +62,18 @@ public:
 			if (Prop->HasAnyPropertyFlags(CPF_RepNotify)) Flags.Append(TEXT(" RepNotify"));
 
 			UClass* OwnerClass = Prop->GetOwnerClass();
-			Result.Appendf(TEXT("  %s %s"), *MCPUtils::FormatPropertyType(Prop), *PropName);
+			UMCPServer::Printf(TEXT("  %s %s"), *MCPUtils::FormatPropertyType(Prop), *PropName);
 			if (OwnerClass && OwnerClass != FoundClass)
-				Result.Appendf(TEXT(" [%s]"), *MCPUtils::FormatName(OwnerClass));
+				UMCPServer::Printf(TEXT(" [%s]"), *MCPUtils::FormatName(OwnerClass));
 			if (Flags.Len() > 0)
-				Result.Appendf(TEXT(" (%s)"), Flags.ToString() + 1); // skip leading space
+				UMCPServer::Printf(TEXT(" (%s)"), Flags.ToString() + 1); // skip leading space
-			Result.Append(TEXT("\n"));
+			UMCPServer::Print(TEXT("\n"));
 			Count++;
 		}
 
 		if (Count == 0)
 		{
-			Result.Append(TEXT("No properties found.\n"));
+			UMCPServer::Print(TEXT("No properties found.\n"));
 		}
 	}
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Editor_ListOpenAssets.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "Editor.h"
 #include "Subsystems/AssetEditorSubsystem.h"
@@ -22,19 +23,19 @@ public:
 		return TEXT("List all currently open asset editors, showing which has focus and whether they have unsaved changes.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		UAssetEditorSubsystem* Sub = GEditor->GetEditorSubsystem<UAssetEditorSubsystem>();
 		if (!Sub)
 		{
-			Result.Append(TEXT("Error: AssetEditorSubsystem not available\n"));
+			UMCPServer::Print(TEXT("Error: AssetEditorSubsystem not available\n"));
 			return;
 		}
 
 		TArray<UObject*> EditedAssets = Sub->GetAllEditedAssets();
 		if (EditedAssets.IsEmpty())
 		{
-			Result.Append(TEXT("No asset editors are open.\n"));
+			UMCPServer::Print(TEXT("No asset editors are open.\n"));
 			return;
 		}
 
@@ -42,7 +43,7 @@ public:
 		{
 			bool bDirty = Asset->GetOutermost()->IsDirty();
 
-			Result.Appendf(TEXT("  %s%s\n"),
+			UMCPServer::Printf(TEXT("  %s%s\n"),
 				bDirty ? TEXT("[unsaved] ") : TEXT(""),
 				*Asset->GetPathName());
 		}

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Editor_OpenAsset.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "Editor.h"
@@ -26,7 +27,7 @@ public:
 		return TEXT("Open an asset in its editor and bring it to focus.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPFetcher F;
 		UObject* Obj = F.Walk(Path).Cast<UObject>();
@@ -35,13 +36,13 @@ public:
 		UAssetEditorSubsystem* Sub = GEditor->GetEditorSubsystem<UAssetEditorSubsystem>();
 		if (!Sub)
 		{
-			Result.Append(TEXT("Error: AssetEditorSubsystem not available\n"));
+			UMCPServer::Print(TEXT("Error: AssetEditorSubsystem not available\n"));
 			return;
 		}
 
 		if (Sub->OpenEditorForAsset(Obj))
-			Result.Appendf(TEXT("Opened editor for %s\n"), *Obj->GetPathName());
+			UMCPServer::Printf(TEXT("Opened editor for %s\n"), *Obj->GetPathName());
 		else
-			Result.Appendf(TEXT("Error: Could not open editor for %s\n"), *Obj->GetPathName());
+			UMCPServer::Printf(TEXT("Error: Could not open editor for %s\n"), *Obj->GetPathName());
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPAssets.h"
 #include "MCPUtils.h"
@@ -32,7 +33,7 @@ public:
 		return TEXT("Create a new UserDefinedEnum asset with the specified values.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPPackageMaker Maker(AssetPath);
 		if (!Maker.Ok()) return;
@@ -64,8 +65,8 @@ public:
 
 		bool bSaved = MCPUtils::SaveGenericPackage(NewEnum);
 
-		Result.Appendf(TEXT("Created %s with %d values\n"), *NewEnum->GetPathName(), EnumValues.Num());
+		UMCPServer::Printf(TEXT("Created %s with %d values\n"), *NewEnum->GetPathName(), EnumValues.Num());
 		if (!bSaved)
-			Result.Append(TEXT("WARNING: Package save failed\n"));
+			UMCPServer::Print(TEXT("WARNING: Package save failed\n"));
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
@@ -49,7 +50,7 @@ public:
 			"Use GraphNodeSearchTypes first to find the exact action name.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPFetcher F;
 		UEdGraph* TargetGraph = F.Walk(Graph).Cast<UEdGraph>();
@@ -68,13 +69,13 @@ public:
 			TArray<TSharedPtr<FEdGraphSchemaAction>> Matches = MCPUtils::SearchGraphActions(TargetGraph, Entry.ActionName, 0, /*ExactMatch=*/true);
 			if (Matches.Num() == 0)
 			{
-				Result.Appendf(TEXT("ERROR: No action found matching '%s'. Use GraphNodeSearchTypes to find available actions.\n"),
+				UMCPServer::Printf(TEXT("ERROR: No action found matching '%s'. Use GraphNodeSearchTypes to find available actions.\n"),
 					*Entry.ActionName);
 				continue;
 			}
 			if (Matches.Num() > 1)
 			{
-				Result.Appendf(TEXT("ERROR: Ambiguous: %d actions match '%s'.\n"),
+				UMCPServer::Printf(TEXT("ERROR: Ambiguous: %d actions match '%s'.\n"),
 					Matches.Num(), *Entry.ActionName);
 				continue;
 			}
@@ -84,18 +85,18 @@ public:
 			UEdGraphNode* NewNode = Matches[0]->PerformAction(TargetGraph, nullptr, Location, /*bSelectNewNode=*/false);
 			if (!NewNode)
 			{
-				Result.Appendf(TEXT("ERROR: PerformAction returned null for '%s'.\n"), *Entry.ActionName);
+				UMCPServer::Printf(TEXT("ERROR: PerformAction returned null for '%s'.\n"), *Entry.ActionName);
 				continue;
 			}
 
 			if (!NewNode->NodeGuid.IsValid())
 				NewNode->CreateNewGuid();
 
-			Result.Appendf(TEXT("Spawned: %s (%s)\n"),
+			UMCPServer::Printf(TEXT("Spawned: %s (%s)\n"),
 				*MCPUtils::FormatName(NewNode), *MCPUtils::FormatName(NewNode->GetClass()));
 			SuccessCount++;
 		}
 
-		Result.Appendf(TEXT("Spawned %d/%d nodes.\n"), SuccessCount, TotalCount);
+		UMCPServer::Printf(TEXT("Spawned %d/%d nodes.\n"), SuccessCount, TotalCount);
 	}
 };

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

@@ -32,7 +32,7 @@ public:
 			"Cannot delete undeletable nodes (entry points, root nodes, etc).");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPFetcher F;
 		UEdGraphNode* FoundNode = F.Walk(Node).Cast<UEdGraphNode>();
@@ -63,6 +63,6 @@ public:
 			Graph->RemoveNode(FoundNode);
 		}
 
-		Result.Appendf(TEXT("Deleted node '%s' from graph '%s'.\n"), *NodeTitle, *GraphName);
+		UMCPServer::Printf(TEXT("Deleted node '%s' from graph '%s'.\n"), *NodeTitle, *GraphName);
 	}
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/GraphNode_Duplicate.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
@@ -39,7 +40,7 @@ public:
 			"Connections are not preserved on the duplicates.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPFetcher F;
 		UEdGraph* TargetGraph = F.Walk(Graph).Cast<UEdGraph>();
@@ -47,7 +48,7 @@ public:
 
 		if (Nodes.Array.Num() == 0)
 		{
-			Result.Append(TEXT("ERROR: Nodes array is empty\n"));
+			UMCPServer::Print(TEXT("ERROR: Nodes array is empty\n"));
 			return;
 		}
 
@@ -67,7 +68,7 @@ public:
 			}
 			if (!Found)
 			{
-				Result.Appendf(TEXT("ERROR: Node '%s' not found in graph\n"), *Name);
+				UMCPServer::Printf(TEXT("ERROR: Node '%s' not found in graph\n"), *Name);
 				continue;
 			}
 			SourceNodes.Add(Found);
@@ -81,7 +82,7 @@ public:
 			UEdGraphNode* NewNode = DuplicateObject<UEdGraphNode>(SourceNode, TargetGraph);
 			if (!NewNode)
 			{
-				Result.Appendf(TEXT("ERROR: Failed to duplicate %s\n"), *MCPUtils::FormatName(SourceNode));
+				UMCPServer::Printf(TEXT("ERROR: Failed to duplicate %s\n"), *MCPUtils::FormatName(SourceNode));
 				continue;
 			}
 
@@ -96,7 +97,7 @@ public:
 			}
 
 			TargetGraph->AddNode(NewNode, false, false);
-			Result.Appendf(TEXT("Duplicated: %s -> %s\n"), *MCPUtils::FormatName(SourceNode), *MCPUtils::FormatName(NewNode));
+			UMCPServer::Printf(TEXT("Duplicated: %s -> %s\n"), *MCPUtils::FormatName(SourceNode), *MCPUtils::FormatName(NewNode));
 		}
 
 	}

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/GraphNode_GetComment.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
@@ -26,14 +27,14 @@ public:
 		return TEXT("Get the comment text and bubble visibility of a node.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPFetcher F;
 		UEdGraphNode* FoundNode = F.Walk(Node).Cast<UEdGraphNode>();
 		if (!FoundNode) return;
 
-		Result.Appendf(TEXT("Node: %s\n"), *MCPUtils::FormatName(FoundNode));
+		UMCPServer::Printf(TEXT("Node: %s\n"), *MCPUtils::FormatName(FoundNode));
-		Result.Appendf(TEXT("Comment: %s\n"), *FoundNode->NodeComment);
+		UMCPServer::Printf(TEXT("Comment: %s\n"), *FoundNode->NodeComment);
-		Result.Appendf(TEXT("BubbleVisible: %s\n"), FoundNode->bCommentBubbleVisible ? TEXT("true") : TEXT("false"));
+		UMCPServer::Printf(TEXT("BubbleVisible: %s\n"), FoundNode->bCommentBubbleVisible ? TEXT("true") : TEXT("false"));
 	}
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/GraphNode_SearchTypes.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
@@ -35,7 +36,7 @@ public:
 			"Returns full action names for use with GraphNodeCreate.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		int32 ClampedMax = FMath::Clamp(MaxResults, 1, 500);
 
@@ -47,16 +48,16 @@ public:
 
 		for (const TSharedPtr<FEdGraphSchemaAction>& Action : Actions)
 		{
-			Result.Appendf(TEXT("%s\n"), *MCPUtils::ActionFullName(Action));
+			UMCPServer::Printf(TEXT("%s\n"), *MCPUtils::ActionFullName(Action));
 		}
 
 		if (Actions.Num() == 0)
 		{
-			Result.Append(TEXT("No matching node types found.\n"));
+			UMCPServer::Print(TEXT("No matching node types found.\n"));
 		}
 		else if (Actions.Num() >= ClampedMax)
 		{
-			Result.Appendf(TEXT("WARNING: Reached limit of %d results. Refine your query or increase MaxResults.\n"), ClampedMax);
+			UMCPServer::Printf(TEXT("WARNING: Reached limit of %d results. Refine your query or increase MaxResults.\n"), ClampedMax);
 		}
 	}
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/GraphNode_SetComment.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
@@ -29,7 +30,7 @@ public:
 		return TEXT("Set a node's comment text. Makes the comment bubble visible if non-empty.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPFetcher F;
 		UEdGraphNode* FoundNode = F.Walk(Node).Cast<UEdGraphNode>();
@@ -44,6 +45,6 @@ public:
 			FoundNode->bCommentBubblePinned = true;
 		}
 
-		Result.Appendf(TEXT("Comment set on %s\n"), *MCPUtils::FormatName(FoundNode));
+		UMCPServer::Printf(TEXT("Comment set on %s\n"), *MCPUtils::FormatName(FoundNode));
 	}
 };

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

@@ -53,8 +53,7 @@ public:
 	// K2 graphs: set pin default values.
 	// -----------------------------------------------------------------------
 
-	void HandleK2Entry(const FSetNodeDefaultEntry& Entry, UEdGraph* GraphObj, const UEdGraphSchema_K2* K2Schema,
+	void HandleK2Entry(const FSetNodeDefaultEntry& Entry, UEdGraph* GraphObj, const UEdGraphSchema_K2* K2Schema)
-		FStringBuilderBase& Result)
 	{
 		MCPFetcher F(GraphObj);
 		UEdGraphPin* Pin = F.Node(Entry.Node).Pin(Entry.Name).Cast<UEdGraphPin>();
@@ -64,7 +63,7 @@ public:
 
 		if (Pin->Direction != EGPD_Input)
 		{
-			Result.Appendf(TEXT("error: %s is an output pin\n"), *MCPUtils::FormatName(Pin));
+			UMCPServer::Printf(TEXT("error: %s is an output pin\n"), *MCPUtils::FormatName(Pin));
 			return;
 		}
 
@@ -77,7 +76,7 @@ public:
 		FString Error = K2Schema->IsPinDefaultValid(Pin, UseDefaultValue, UseDefaultObject, UseDefaultText);
 		if (!Error.IsEmpty())
 		{
-			Result.Appendf(TEXT("error: %s: %s\n"), *MCPUtils::FormatName(Pin), *Error);
+			UMCPServer::Printf(TEXT("error: %s: %s\n"), *MCPUtils::FormatName(Pin), *Error);
 			return;
 		}
 		UMCPServer::AddTouchedObject(Node);
@@ -88,8 +87,7 @@ public:
 	// Material graphs: set material expression properties.
 	// -----------------------------------------------------------------------
 
-	void HandleMaterialEntry(const FSetNodeDefaultEntry& Entry, UEdGraph* GraphObj,
+	void HandleMaterialEntry(const FSetNodeDefaultEntry& Entry, UEdGraph* GraphObj)
-		FStringBuilderBase& Result)
 	{
 		MCPFetcher F(GraphObj);
 		UEdGraphNode* Node = F.Node(Entry.Node).Cast<UEdGraphNode>();
@@ -106,7 +104,7 @@ public:
 
 	// -----------------------------------------------------------------------
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		// Fetch the graph once.
 		MCPFetcher GraphFetcher;
@@ -119,7 +117,7 @@ public:
 
 		if (!K2Schema && !MGSchema)
 		{
-			Result.Appendf(TEXT("error: unsupported graph schema %s\n"), *Schema->GetClass()->GetName());
+			UMCPServer::Printf(TEXT("error: unsupported graph schema %s\n"), *Schema->GetClass()->GetName());
 			return;
 		}
 
@@ -130,11 +128,11 @@ public:
 				continue;
 
 			if (K2Schema)
-				HandleK2Entry(Entry, GraphObj, K2Schema, Result);
+				HandleK2Entry(Entry, GraphObj, K2Schema);
 			else if (MGSchema)
-				HandleMaterialEntry(Entry, GraphObj, Result);
+				HandleMaterialEntry(Entry, GraphObj);
 		}
 
-		Result.Appendf(TEXT("Done.\n"));
+		UMCPServer::Printf(TEXT("Done.\n"));
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
@@ -46,7 +47,7 @@ public:
 		return TEXT("Reposition one or more nodes in a Blueprint graph.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPFetcher F;
 		UBlueprint* BP = F.Walk(Blueprint).Cast<UBlueprint>();
@@ -65,10 +66,10 @@ public:
 
 			Node->NodePosX = Entry.X;
 			Node->NodePosY = Entry.Y;
-			Result.Appendf(TEXT("Moved %s to (%d, %d)\n"), *MCPUtils::FormatName(Node), Entry.X, Entry.Y);
+			UMCPServer::Printf(TEXT("Moved %s to (%d, %d)\n"), *MCPUtils::FormatName(Node), Entry.X, Entry.Y);
 			SuccessCount++;
 		}
 
-		Result.Appendf(TEXT("Moved %d/%d nodes.\n"), SuccessCount, Nodes.Array.Num());
+		UMCPServer::Printf(TEXT("Moved %d/%d nodes.\n"), SuccessCount, Nodes.Array.Num());
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
@@ -45,7 +46,7 @@ public:
 		return TEXT("Connect pins between nodes in a graph (Blueprint or Material).");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPFetcher F;
 		UEdGraph* G = F.Walk(Graph).ToGraph().Cast<UEdGraph>();
@@ -72,7 +73,7 @@ public:
 			const FPinConnectionResponse Response = Schema->CanCreateConnection(SourcePin, TargetPin);
 			if (Response.Response == CONNECT_RESPONSE_DISALLOW)
 			{
-				Result.Appendf(TEXT("error: Cannot connect %s.%s to %s.%s: %s\n"),
+				UMCPServer::Printf(TEXT("error: Cannot connect %s.%s to %s.%s: %s\n"),
 					*MCPUtils::FormatName(SourcePin->GetOwningNode()), *MCPUtils::FormatName(SourcePin),
 					*MCPUtils::FormatName(TargetPin->GetOwningNode()), *MCPUtils::FormatName(TargetPin),
 					*Response.Message.ToString());
@@ -83,6 +84,6 @@ public:
 			SuccessCount++;
 		}
 
-		Result.Appendf(TEXT("Connected %d/%d pins.\n"), SuccessCount, TotalCount);
+		UMCPServer::Printf(TEXT("Connected %d/%d pins.\n"), SuccessCount, TotalCount);
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
@@ -45,7 +46,7 @@ public:
 			"Can disconnect a specific link or all links on a pin.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPFetcher F;
 		UEdGraph* G = F.Walk(Graph).ToGraph().Cast<UEdGraph>();
@@ -73,7 +74,7 @@ public:
 
 				if (!Pin->LinkedTo.Contains(Target))
 				{
-					Result.Appendf(TEXT("Error: %s.%s is not connected to %s.%s\n"),
+					UMCPServer::Printf(TEXT("Error: %s.%s is not connected to %s.%s\n"),
 						*MCPUtils::FormatName(Pin->GetOwningNode()), *MCPUtils::FormatName(Pin),
 						*MCPUtils::FormatName(Target->GetOwningNode()), *MCPUtils::FormatName(Target));
 					continue;
@@ -91,14 +92,14 @@ public:
 				}
 			}
 
-			Result.Appendf(TEXT("Disconnected %d link(s) from %s.%s\n"),
+			UMCPServer::Printf(TEXT("Disconnected %d link(s) from %s.%s\n"),
 				DisconnectedCount,
 				*MCPUtils::FormatName(Pin->GetOwningNode()), *MCPUtils::FormatName(Pin));
 			SuccessCount++;
 			TotalDisconnected += DisconnectedCount;
 		}
 
-		Result.Appendf(TEXT("Done: %d/%d succeeded, %d links broken.\n"),
+		UMCPServer::Printf(TEXT("Done: %d/%d succeeded, %d links broken.\n"),
 			SuccessCount, Disconnections.Array.Num(), TotalDisconnected);
 	}
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Graph_Dump.h

@@ -32,7 +32,7 @@ public:
 			"If given a blueprint or material, dumps all graphs. If given a specific graph, dumps only that one.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPFetcher F;
 		F.Walk(Path);

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPAssets.h"
 #include "MCPUtils.h"
@@ -31,7 +32,7 @@ public:
 		return TEXT("Create a new UMaterialFunction asset with an optional description.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPPackageMaker Maker(AssetPath);
 		if (!Maker.Ok()) return;
@@ -46,8 +47,8 @@ public:
 
 		bool bSaved = MCPUtils::SaveGenericPackage(MF);
 
-		Result.Appendf(TEXT("Created %s\n"), *MF->GetPathName());
+		UMCPServer::Printf(TEXT("Created %s\n"), *MF->GetPathName());
 		if (!bSaved)
-			Result.Append(TEXT("WARNING: Package save failed\n"));
+			UMCPServer::Print(TEXT("WARNING: Package save failed\n"));
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
@@ -36,7 +37,7 @@ public:
 		return TEXT("Remove a parameter override from a Material Instance, reverting it to the parent material's value.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPFetcher F;
 		UMaterialInstanceConstant* MI = F.Asset(Path).Cast<UMaterialInstanceConstant>();
@@ -66,13 +67,13 @@ public:
 
 		if (Removed == 0)
 		{
-			Result.Appendf(TEXT("No override found for parameter '%s' (association=%s layer=%d) on %s"),
+			UMCPServer::Printf(TEXT("No override found for parameter '%s' (association=%s layer=%d) on %s"),
 				*Parameter, *ParameterAssociation, ParameterLayer, *MCPUtils::FormatName(MI));
 			return;
 		}
 
 		MCPUtils::SaveGenericPackage(MI);
-		Result.Appendf(TEXT("Cleared override for '%s' on %s\n"),
+		UMCPServer::Printf(TEXT("Cleared override for '%s' on %s\n"),
 			*Parameter, *MCPUtils::FormatName(MI));
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPAssets.h"
 #include "MCPUtils.h"
@@ -33,7 +34,7 @@ public:
 		return TEXT("Create a new Material Instance Constant asset with a specified parent material.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPPackageMaker Maker(AssetPath);
 		if (!Maker.Ok()) return;
@@ -63,7 +64,7 @@ public:
 
 		if (!ParentMaterialObj)
 		{
-			Result.Appendf(TEXT("ERROR: Parent material '%s' not found\n"), *ParentMaterial);
+			UMCPServer::Printf(TEXT("ERROR: Parent material '%s' not found\n"), *ParentMaterial);
 			return;
 		}
 
@@ -77,14 +78,14 @@ public:
 		// Save.
 		bool bSaved = MCPUtils::SaveGenericPackage(MI);
 
-		Result.Appendf(TEXT("Created %s\n"), *MI->GetPathName());
+		UMCPServer::Printf(TEXT("Created %s\n"), *MI->GetPathName());
 		if (UMaterialInstance* ParentMI = Cast<UMaterialInstance>(ParentMaterialObj))
-			Result.Appendf(TEXT("Parent: %s\n"), *MCPUtils::FormatName(ParentMI));
+			UMCPServer::Printf(TEXT("Parent: %s\n"), *MCPUtils::FormatName(ParentMI));
 		else if (UMaterial* ParentMat = Cast<UMaterial>(ParentMaterialObj))
-			Result.Appendf(TEXT("Parent: %s\n"), *MCPUtils::FormatName(ParentMat));
+			UMCPServer::Printf(TEXT("Parent: %s\n"), *MCPUtils::FormatName(ParentMat));
 		else
-			Result.Appendf(TEXT("Parent: %s\n"), *ParentMaterialObj->GetPathName());
+			UMCPServer::Printf(TEXT("Parent: %s\n"), *ParentMaterialObj->GetPathName());
 		if (!bSaved)
-			Result.Append(TEXT("WARNING: Package save failed\n"));
+			UMCPServer::Print(TEXT("WARNING: Package save failed\n"));
 	}
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/MaterialInstance_DumpParameters.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
@@ -27,7 +28,7 @@ public:
 		return TEXT("List all parameters on a Material Instance, showing current values and which are overridden.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPFetcher F;
 		UMaterialInstanceConstant* MI = F.Asset(Path).Cast<UMaterialInstanceConstant>();
@@ -40,8 +41,8 @@ public:
 		for (auto& [Info, Meta] : AllParams)
 		{
 			if (!Meta.bOverride) continue;
-			if (!bHasOverrides) { Result.Append(TEXT("\nOverridden Parameters:\n")); bHasOverrides = true; }
+			if (!bHasOverrides) { UMCPServer::Print(TEXT("\nOverridden Parameters:\n")); bHasOverrides = true; }
-			MCPUtils::FormatMaterialParameter(Result, Info, Meta);
+			MCPUtils::FormatMaterialParameter(Info, Meta);
 		}
 
 		// Inherited (non-overridden) parameters.
@@ -49,8 +50,8 @@ public:
 		for (auto& [Info, Meta] : AllParams)
 		{
 			if (Meta.bOverride) continue;
-			if (!bHasInherited) { Result.Append(TEXT("\nInherited Parameters (not overridden):\n")); bHasInherited = true; }
+			if (!bHasInherited) { UMCPServer::Print(TEXT("\nInherited Parameters (not overridden):\n")); bHasInherited = true; }
-			MCPUtils::FormatMaterialParameter(Result, Info, Meta);
+			MCPUtils::FormatMaterialParameter(Info, Meta);
 		}
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
@@ -40,7 +41,7 @@ public:
 		return TEXT("Set a parameter override on a Material Instance.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPFetcher F;
 		UMaterialInstanceConstant* MI = F.Asset(Path).Cast<UMaterialInstanceConstant>();
@@ -59,13 +60,13 @@ public:
 		FMaterialParameterMetadata* Found = AllParams.Find(ParamID);
 		if (!Found)
 		{
-			Result.Appendf(TEXT("No parameter named '%s' with association=%s layer=%d"),
+			UMCPServer::Printf(TEXT("No parameter named '%s' with association=%s layer=%d"),
 				*Parameter, *ParameterAssociation, ParameterLayer);
 			return;
 		}
 		if (Found->PrimitiveDataIndex != INDEX_NONE)
 		{
-			Result.Appendf(TEXT("Parameter '%s' uses custom primitive data and cannot be set on a material instance"), *Parameter);
+			UMCPServer::Printf(TEXT("Parameter '%s' uses custom primitive data and cannot be set on a material instance"), *Parameter);
 			return;
 		}
 
@@ -78,7 +79,7 @@ public:
 			float ScalarValue;
 			if (!FDefaultValueHelper::ParseFloat(Value, ScalarValue))
 			{
-				Result.Appendf(TEXT("Failed to parse '%s' as a float"), *Value);
+				UMCPServer::Printf(TEXT("Failed to parse '%s' as a float"), *Value);
 				return;
 			}
 			MI->SetScalarParameterValueEditorOnly(ParamID, ScalarValue);
@@ -89,19 +90,19 @@ public:
 			FLinearColor Color;
 			if (!Color.InitFromString(Value))
 			{
-				Result.Appendf(TEXT("Failed to parse '%s' as a color/vector (expected format: '(R=1,G=0,B=0,A=1)')"), *Value);
+				UMCPServer::Printf(TEXT("Failed to parse '%s' as a color/vector (expected format: '(R=1,G=0,B=0,A=1)')"), *Value);
 				return;
 			}
 			MI->SetVectorParameterValueEditorOnly(ParamID, Color);
 			break;
 		}
 		default:
-			Result.Appendf(TEXT("Parameters of type %d (see EMaterialParameterType) are not implemented"), (int)Type);
+			UMCPServer::Printf(TEXT("Parameters of type %d (see EMaterialParameterType) are not implemented"), (int)Type);
 			return;
 		}
 		MCPUtils::SaveGenericPackage(MI);
 
-		Result.Appendf(TEXT("Set '%s' = %s on %s\n"),
+		UMCPServer::Printf(TEXT("Set '%s' = %s on %s\n"),
 			*Parameter, *Value, *MCPUtils::FormatName(MI));
 	}
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Material_Compile.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
@@ -26,7 +27,7 @@ public:
 		return TEXT("Force recompile a material and check for compilation errors.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		// Load material
 		MCPFetcher F;
@@ -47,14 +48,14 @@ public:
 
 		if (Errors.IsEmpty())
 		{
-			Result.Appendf(TEXT("%s compiled successfully.\n"), *MCPUtils::FormatName(MaterialObj));
+			UMCPServer::Printf(TEXT("%s compiled successfully.\n"), *MCPUtils::FormatName(MaterialObj));
 		}
 		else
 		{
-			Result.Appendf(TEXT("%s compiled with %d error(s):\n"), *MCPUtils::FormatName(MaterialObj), Errors.Num());
+			UMCPServer::Printf(TEXT("%s compiled with %d error(s):\n"), *MCPUtils::FormatName(MaterialObj), Errors.Num());
 			for (const FString& Err : Errors)
 			{
-				Result.Appendf(TEXT("  %s\n"), *Err);
+				UMCPServer::Printf(TEXT("  %s\n"), *Err);
 			}
 		}
 	}

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPAssets.h"
 #include "MCPUtils.h"
@@ -38,7 +39,7 @@ public:
 		return TEXT("Create a new UMaterial asset with optional domain, blend mode, and two-sided settings.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPPackageMaker Maker(AssetPath);
 		if (!Maker.Ok()) return;
@@ -73,11 +74,11 @@ public:
 
 		bool bSaved = MCPUtils::SaveGenericPackage(MaterialObj);
 
-		Result.Appendf(TEXT("Created %s\n"), *MaterialObj->GetPathName());
+		UMCPServer::Printf(TEXT("Created %s\n"), *MaterialObj->GetPathName());
-		Result.Appendf(TEXT("Domain: %s\n"), *MCPUtils::EnumToString(MaterialObj->MaterialDomain, TEXT("MD_")));
+		UMCPServer::Printf(TEXT("Domain: %s\n"), *MCPUtils::EnumToString(MaterialObj->MaterialDomain, TEXT("MD_")));
-		Result.Appendf(TEXT("BlendMode: %s\n"), *MCPUtils::EnumToString(MaterialObj->BlendMode, TEXT("BLEND_")));
+		UMCPServer::Printf(TEXT("BlendMode: %s\n"), *MCPUtils::EnumToString(MaterialObj->BlendMode, TEXT("BLEND_")));
-		Result.Appendf(TEXT("TwoSided: %s\n"), MaterialObj->TwoSided ? TEXT("true") : TEXT("false"));
+		UMCPServer::Printf(TEXT("TwoSided: %s\n"), MaterialObj->TwoSided ? TEXT("true") : TEXT("false"));
 		if (!bSaved)
-			Result.Append(TEXT("WARNING: Package save failed\n"));
+			UMCPServer::Print(TEXT("WARNING: Package save failed\n"));
 	}
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Material_DumpParameters.h

@@ -27,7 +27,7 @@ public:
 		return TEXT("List all parameters on a Material, showing their default values.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPFetcher F;
 		UMaterial* Mat = F.Asset(Path).Cast<UMaterial>();
@@ -37,7 +37,7 @@ public:
 
 		for (auto& [Info, Meta] : AllParams)
 		{
-			MCPUtils::FormatMaterialParameter(Result, Info, Meta);
+			MCPUtils::FormatMaterialParameter(Info, Meta);
 		}
 	}
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Property_Dump.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPProperty.h"
@@ -36,7 +37,7 @@ public:
 			"showing current values and which properties are editable.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		// Resolve the path to an object and get its editable template.
 		MCPFetcher F;
@@ -70,9 +71,9 @@ public:
 		for (const FString& Category : Categories)
 		{
 			if (Category.IsEmpty())
-				Result.Append(TEXT("\nUncategorized:\n"));
+				UMCPServer::Print(TEXT("\nUncategorized:\n"));
 			else
-				Result.Appendf(TEXT("\n%s:\n"), *Category);
+				UMCPServer::Printf(TEXT("\n%s:\n"), *Category);
 
 			for (MCPProperty& P : ByCategory[Category])
 			{
@@ -83,7 +84,7 @@ public:
 					ValueStr = ValueStr.Left(80) + TEXT("...");
 
 				bool bEditable = !P->HasAnyPropertyFlags(CPF_EditConst);
-				Result.Appendf(TEXT("    %s %s %s = %s\n"),
+				UMCPServer::Printf(TEXT("    %s %s %s = %s\n"),
 					bEditable ? TEXT("editable") : TEXT("readonly"),
 					*MCPUtils::FormatPropertyType(P.Prop),
 					*PropName,
@@ -92,6 +93,6 @@ public:
 		}
 
 		if (Props.IsEmpty())
-			Result.Append(TEXT("  (no blueprint-visible properties found)\n"));
+			UMCPServer::Print(TEXT("  (no blueprint-visible properties found)\n"));
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPProperty.h"
@@ -29,7 +30,7 @@ public:
 		return TEXT("Get the value of a single property on an object resolved via MCPFetcher path.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPFetcher F;
 		UObject* Template = F.Walk(Path).Template().Cast<UObject>();
@@ -38,7 +39,7 @@ public:
 		MCPProperty P = MCPProperty::GetOneExactMatch(Template, CPF_Edit, Property);
 		if (!P) return;
 
-		Result.Append(P.GetText());
+		UMCPServer::Print(P.GetText());
-		Result.Append(TEXT("\n"));
+		UMCPServer::Print(TEXT("\n"));
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPProperty.h"
@@ -30,7 +31,7 @@ public:
 			"Properties is a JSON object like {\"TwoSided\": \"true\", \"BlendMode\": \"BLEND_Translucent\"}.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		// Resolve the path to an object and get its editable template.
 		MCPFetcher F;
@@ -39,7 +40,7 @@ public:
 
 		if (!Properties.Json || Properties.Json->Values.Num() == 0)
 		{
-			Result.Append(TEXT("Error: No properties specified\n"));
+			UMCPServer::Print(TEXT("Error: No properties specified\n"));
 			return;
 		}
 
@@ -53,7 +54,7 @@ public:
 			FString ValueStr;
 			if (!Pair.Value->TryGetString(ValueStr))
 			{
-				Result.Appendf(TEXT("Error: Value for '%s' must be a string\n"), *Pair.Key);
+				UMCPServer::Printf(TEXT("Error: Value for '%s' must be a string\n"), *Pair.Key);
 				return;
 			}
 			Resolved.Emplace(P, ValueStr);
@@ -71,8 +72,8 @@ public:
 		// Save.
 		bool bSaved = MCPUtils::SaveGenericPackage(Template);
 
-		Result.Appendf(TEXT("Set %d/%d properties.\n"), SuccessCount, Properties.Json->Values.Num());
+		UMCPServer::Printf(TEXT("Set %d/%d properties.\n"), SuccessCount, Properties.Json->Values.Num());
 		if (!bSaved)
-			Result.Append(TEXT("Warning: Save failed\n"));
+			UMCPServer::Print(TEXT("Warning: Save failed\n"));
 	}
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/ShowCommands.h

@@ -3,6 +3,7 @@
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
+#include "MCPServer.h"
 #include "MCPUtils.h"
 #include "ShowCommands.generated.h"
 
@@ -23,7 +24,7 @@ public:
 		return TEXT("List all available commands with their descriptions.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	void EmitCommandList()
 	{
 		FString QueryLower = Query.ToLower();
 		FString PrevGroup;
@@ -39,40 +40,47 @@ public:
 			if (Group != PrevGroup)
 			{
 				if (!PrevGroup.IsEmpty())
-					Result.Append(TEXT("\n"));
+					UMCPServer::Print(TEXT("\n"));
 				PrevGroup = Group;
 			}
 
 			if (Verbose)
 			{
-				MCPUtils::FormatCommandHelp(Class, Result);
+				MCPUtils::FormatCommandHelp(Class);
 				continue;
 			}
-			Result.Append(ToolName);
+			UMCPServer::Print(ToolName);
-			Result.Append(TEXT("("));
+			UMCPServer::Print(TEXT("("));
 			bool bFirst = true;
 			for (TFieldIterator<FProperty> PropIt(Class, EFieldIterationFlags::None); PropIt; ++PropIt)
 			{
-				if (!bFirst) Result.Append(TEXT(","));
+				if (!bFirst) UMCPServer::Print(TEXT(","));
 				bFirst = false;
-				if (PropIt->HasMetaData(TEXT("Optional"))) Result.Append(TEXT("?"));
+				if (PropIt->HasMetaData(TEXT("Optional"))) UMCPServer::Print(TEXT("?"));
-				Result.Append(MCPUtils::FormatPropertyType(*PropIt));
+				UMCPServer::Print(MCPUtils::FormatPropertyType(*PropIt));
-				Result.Append(TEXT(" "));
+				UMCPServer::Print(TEXT(" "));
-				Result.Append(MCPUtils::PropertyNameToJsonKey(PropIt->GetName()));
+				UMCPServer::Print(MCPUtils::PropertyNameToJsonKey(PropIt->GetName()));
 			}
-			Result.Append(TEXT(")\n"));
+			UMCPServer::Print(TEXT(")\n"));
 		}
+	}
+
+	virtual void Handle() override
+	{
+		UMCPServer::Printf(TEXT("\n"));
+
+		EmitCommandList();
 
 		// Append Path documentation.
-		Result.Append(TEXT("\n"));
+		UMCPServer::Print(TEXT("\n"));
-		Result.Append(TEXT("Some commands take a Path parameter. A Path starts with an asset\n"));
+		UMCPServer::Print(TEXT("Some commands take a Path parameter. A Path starts with an asset\n"));
-		Result.Append(TEXT("package path (e.g. /Game/Widgets/WB_Hotkeys), followed by zero or\n"));
+		UMCPServer::Print(TEXT("package path (e.g. /Game/Widgets/WB_Hotkeys), followed by zero or\n"));
-		Result.Append(TEXT("more comma-separated steps that navigate into the asset:\n"));
+		UMCPServer::Print(TEXT("more comma-separated steps that navigate into the asset:\n"));
-		Result.Append(TEXT("\n"));
+		UMCPServer::Print(TEXT("\n"));
 		for (const MCPFetcher::FWalker& W : MCPFetcher::GetWalkerTable())
 		{
-			Result.Appendf(TEXT("  %s — %s\n"), W.Key, W.Description);
+			UMCPServer::Printf(TEXT("  %s — %s\n"), W.Key, W.Description);
 		}
-		Result.Append(TEXT("\nExample: /Game/Widgets/WB_Hotkeys,graph:EventGraph,node:Self_Reference_03,pin:Result\n"));
+		UMCPServer::Print(TEXT("\nExample: /Game/Widgets/WB_Hotkeys,graph:EventGraph,node:Self_Reference_03,pin:Result\n"));
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPAssets.h"
 #include "MCPFetcher.h"
@@ -49,7 +50,7 @@ public:
 			"Optionally assign an animation asset to the state.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		// Resolve the anim blueprint
 		MCPFetcher F;
@@ -60,14 +61,14 @@ public:
 		UAnimationStateMachineGraph* SMGraph = MCPUtils::FindStateMachineGraph(AnimBP, Graph);
 		if (!SMGraph)
 		{
-			Result.Appendf(TEXT("ERROR: State machine graph '%s' not found in %s\n"), *Graph, *MCPUtils::FormatName(AnimBP));
+			UMCPServer::Printf(TEXT("ERROR: State machine graph '%s' not found in %s\n"), *Graph, *MCPUtils::FormatName(AnimBP));
 			return;
 		}
 
 		// Check for duplicate state name
 		if (MCPUtils::FindStateByName(SMGraph, StateName))
 		{
-			Result.Appendf(TEXT("ERROR: State '%s' already exists in %s\n"), *StateName, *MCPUtils::FormatName(SMGraph));
+			UMCPServer::Printf(TEXT("ERROR: State '%s' already exists in %s\n"), *StateName, *MCPUtils::FormatName(SMGraph));
 			return;
 		}
 
@@ -110,7 +111,7 @@ public:
 		FKismetEditorUtilities::CompileBlueprint(AnimBP);
 		MCPUtils::SaveBlueprintPackage(AnimBP);
 
-		Result.Appendf(TEXT("Created state '%s' in %s\n"), *StateName, *MCPUtils::FormatName(SMGraph));
+		UMCPServer::Printf(TEXT("Created state '%s' in %s\n"), *StateName, *MCPUtils::FormatName(SMGraph));
-		Result.Appendf(TEXT("  node: %s\n"), *MCPUtils::FormatName(NewState));
+		UMCPServer::Printf(TEXT("  node: %s\n"), *MCPUtils::FormatName(NewState));
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPAssets.h"
 #include "MCPUtils.h"
@@ -48,7 +49,7 @@ public:
 		return TEXT("Add a transition between two states in an animation state machine graph.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPAssets<UAnimBlueprint> Assets;
 		if (!Assets.Exact(Blueprint).ENone().ETwo().Load()) return;
@@ -57,7 +58,7 @@ public:
 		UAnimationStateMachineGraph* SMGraph = MCPUtils::FindStateMachineGraph(AnimBP, Graph);
 		if (!SMGraph)
 		{
-			Result.Appendf(TEXT("ERROR: State machine graph '%s' not found in '%s'\n"), *Graph, *MCPUtils::FormatName(AnimBP));
+			UMCPServer::Printf(TEXT("ERROR: State machine graph '%s' not found in '%s'\n"), *Graph, *MCPUtils::FormatName(AnimBP));
 			return;
 		}
 
@@ -92,7 +93,7 @@ public:
 		FKismetEditorUtilities::CompileBlueprint(AnimBP);
 		MCPUtils::SaveBlueprintPackage(AnimBP);
 
-		Result.Appendf(TEXT("Created transition %s -> %s: %s\n"),
+		UMCPServer::Printf(TEXT("Created transition %s -> %s: %s\n"),
 			*FromState, *ToState, *MCPUtils::FormatName(TransNode));
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
@@ -33,7 +34,7 @@ public:
 		return TEXT("Remove a state and its connected transitions from an animation state machine graph.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		// Fetch the state machine graph via MCPFetcher
 		MCPFetcher F;
@@ -47,7 +48,7 @@ public:
 		UBlueprint* BP = Cast<UBlueprint>(SMGraph->GetOuter()->GetOuter());
 		if (!BP)
 		{
-			Result.Append(TEXT("ERROR: Could not find owning blueprint.\n"));
+			UMCPServer::Print(TEXT("ERROR: Could not find owning blueprint.\n"));
 			return;
 		}
 
@@ -75,7 +76,7 @@ public:
 		FKismetEditorUtilities::CompileBlueprint(BP);
 		MCPUtils::SaveBlueprintPackage(BP);
 
-		Result.Appendf(TEXT("Removed state %s and %d transition(s).\n"),
+		UMCPServer::Printf(TEXT("Removed state %s and %d transition(s).\n"),
 			*MCPUtils::FormatName(StateNode), RemovedTransitions);
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPAssets.h"
 #include "MCPFetcher.h"
@@ -43,7 +44,7 @@ public:
 		return TEXT("Set or replace the animation sequence played by a state in an animation state machine.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		// Resolve the anim blueprint
 		MCPFetcher F;
@@ -54,7 +55,7 @@ public:
 		UAnimationStateMachineGraph* SMGraph = MCPUtils::FindStateMachineGraph(AnimBP, Graph);
 		if (!SMGraph)
 		{
-			Result.Appendf(TEXT("ERROR: State machine graph '%s' not found in %s\n"), *Graph, *MCPUtils::FormatName(AnimBP));
+			UMCPServer::Printf(TEXT("ERROR: State machine graph '%s' not found in %s\n"), *Graph, *MCPUtils::FormatName(AnimBP));
 			return;
 		}
 
@@ -65,7 +66,7 @@ public:
 		UEdGraph* InnerGraph = StateNode->GetBoundGraph();
 		if (!InnerGraph)
 		{
-			Result.Appendf(TEXT("ERROR: State '%s' has no bound graph\n"), *StateName);
+			UMCPServer::Printf(TEXT("ERROR: State '%s' has no bound graph\n"), *StateName);
 			return;
 		}
 
@@ -102,8 +103,8 @@ public:
 		MCPUtils::SaveBlueprintPackage(AnimBP);
 
 		if (bCreatedNew)
-			Result.Appendf(TEXT("Created sequence player in state '%s', assigned %s\n"), *StateName, *MCPUtils::FormatName(AnimSeq));
+			UMCPServer::Printf(TEXT("Created sequence player in state '%s', assigned %s\n"), *StateName, *MCPUtils::FormatName(AnimSeq));
 		else
-			Result.Appendf(TEXT("Updated sequence player in state '%s' to %s\n"), *StateName, *MCPUtils::FormatName(AnimSeq));
+			UMCPServer::Printf(TEXT("Updated sequence player in state '%s' to %s\n"), *StateName, *MCPUtils::FormatName(AnimSeq));
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPAssets.h"
 #include "MCPFetcher.h"
@@ -53,7 +54,7 @@ public:
 			"and optionally wire blueprint variables to the X and Y axis inputs.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		// Load the anim blueprint
 		MCPAssets<UAnimBlueprint> Assets;
@@ -62,13 +63,13 @@ public:
 
 		// 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; }
+		if (!SMGraph) { UMCPServer::Printf(TEXT("ERROR: State machine graph '%s' not found\n"), *Graph); return; }
 
 		UAnimStateNode* StateNode = MCPUtils::FindStateByName(SMGraph, StateName);
 		if (!StateNode) return;
 
 		UEdGraph* InnerGraph = StateNode->GetBoundGraph();
-		if (!InnerGraph) { Result.Appendf(TEXT("ERROR: State '%s' has no bound graph\n"), *StateName); return; }
+		if (!InnerGraph) { UMCPServer::Printf(TEXT("ERROR: State '%s' has no bound graph\n"), *StateName); return; }
 
 		// Load the blend space asset
 		MCPAssets<UBlendSpace> BlendSpaceAssets;
@@ -100,17 +101,17 @@ public:
 		ConnectToOutputPose(BSNode, InnerGraph);
 
 		// Wire X and Y variables if provided
-		WireVariable(AnimBP, InnerGraph, BSNode, XVariable, TEXT("X"), Result);
+		WireVariable(AnimBP, InnerGraph, BSNode, XVariable, TEXT("X"));
-		WireVariable(AnimBP, InnerGraph, BSNode, YVariable, TEXT("Y"), Result);
+		WireVariable(AnimBP, InnerGraph, BSNode, YVariable, TEXT("Y"));
 
 		// Compile and save
 		FKismetEditorUtilities::CompileBlueprint(AnimBP);
 		bool bSaved = MCPUtils::SaveBlueprintPackage(AnimBP);
 
-		Result.Appendf(TEXT("BlendSpacePlayer %s placed in state %s\n"),
+		UMCPServer::Printf(TEXT("BlendSpacePlayer %s placed in state %s\n"),
 			*MCPUtils::FormatName(BSNode), *StateName);
 		if (!bSaved)
-			Result.Append(TEXT("WARNING: Failed to save package\n"));
+			UMCPServer::Print(TEXT("WARNING: Failed to save package\n"));
 	}
 
 private:
@@ -160,7 +161,7 @@ private:
 
 	void WireVariable(UAnimBlueprint* AnimBP, UEdGraph* InnerGraph,
 		UAnimGraphNode_BlendSpacePlayer* BSNode, const FString& VarName,
-		const TCHAR* PinName, FStringBuilderBase& Result)
+		const TCHAR* PinName)
 	{
 		if (VarName.IsEmpty()) return;
 
@@ -185,7 +186,7 @@ private:
 		}
 		if (!bVarFound)
 		{
-			Result.Appendf(TEXT("WARNING: Variable '%s' not found, skipping %s wire\n"), *VarName, PinName);
+			UMCPServer::Printf(TEXT("WARNING: Variable '%s' not found, skipping %s wire\n"), *VarName, PinName);
 			return;
 		}
 

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPAssets.h"
 #include "MCPUtils.h"
@@ -53,7 +54,7 @@ public:
 		return TEXT("Update properties on an existing transition between two states in an animation state machine.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPAssets<UAnimBlueprint> Assets;
 		if (!Assets.Exact(Blueprint).ENone().ETwo().Load()) return;
@@ -62,14 +63,14 @@ public:
 		UAnimationStateMachineGraph* SMGraph = MCPUtils::FindStateMachineGraph(AnimBP, Graph);
 		if (!SMGraph)
 		{
-			Result.Appendf(TEXT("ERROR: State machine graph '%s' not found in '%s'\n"), *Graph, *MCPUtils::FormatName(AnimBP));
+			UMCPServer::Printf(TEXT("ERROR: State machine graph '%s' not found in '%s'\n"), *Graph, *MCPUtils::FormatName(AnimBP));
 			return;
 		}
 
 		UAnimStateTransitionNode* TransNode = MCPUtils::FindTransition(SMGraph, FromState, ToState);
 		if (!TransNode)
 		{
-			Result.Appendf(TEXT("ERROR: Transition from '%s' to '%s' not found in graph '%s'\n"),
+			UMCPServer::Printf(TEXT("ERROR: Transition from '%s' to '%s' not found in graph '%s'\n"),
 				*FromState, *ToState, *Graph);
 			return;
 		}
@@ -85,7 +86,7 @@ public:
 		FKismetEditorUtilities::CompileBlueprint(AnimBP);
 		MCPUtils::SaveBlueprintPackage(AnimBP);
 
-		Result.Appendf(TEXT("Updated transition %s -> %s: %s\n"),
+		UMCPServer::Printf(TEXT("Updated transition %s -> %s: %s\n"),
 			*FromState, *ToState, *MCPUtils::FormatName(TransNode));
 	}
 };

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

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "MCPServer.h"
 #include "MCPHandler.h"
 #include "MCPAssets.h"
 #include "MCPUtils.h"
@@ -45,7 +46,7 @@ public:
 		return TEXT("Create a new UserDefinedStruct asset with optional initial properties.");
 	}
 
-	virtual void Handle(FStringBuilderBase& Result) override
+	virtual void Handle() override
 	{
 		MCPPackageMaker Maker(AssetPath);
 		if (!Maker.Ok()) return;
@@ -88,10 +89,10 @@ public:
 
 		bool bSaved = MCPUtils::SaveGenericPackage(NewStruct);
 
-		Result.Appendf(TEXT("Created %s\n"), *NewStruct->GetPathName());
+		UMCPServer::Printf(TEXT("Created %s\n"), *NewStruct->GetPathName());
 		if (PropsAdded > 0)
-			Result.Appendf(TEXT("Properties added: %d\n"), PropsAdded);
+			UMCPServer::Printf(TEXT("Properties added: %d\n"), PropsAdded);
 		if (!bSaved)
-			Result.Append(TEXT("WARNING: Package save failed\n"));
+			UMCPServer::Print(TEXT("WARNING: Package save failed\n"));
 	}
 };

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

@@ -260,57 +260,17 @@ TStatId UMCPServer::GetStatId() const
 
 FString UMCPServer::HandleRequest(const FString& Line)
 {
-	// Turn the request string into a JSON tree.
-	TSharedPtr<FJsonObject> Request;
-	TSharedRef<TJsonReader<>> Reader = TJsonReaderFactory<>::Create(Line);
-	FJsonSerializer::Deserialize(Reader, Request);
-	if (!Request.IsValid())
-	{
-		return TEXT("Request is not valid JSON");
-	}
-
-	// Extract the command from the request.
-	FString Command;
-	if (!Request->TryGetStringField(TEXT("command"), Command))
-	{
-		return TEXT("Request does not contain 'command' parameter");
-	}
-	Request->RemoveField(TEXT("command"));
-
-	// Find the handler UClass for the specified command.
-	UClass** HandlerClass = MCPHandlerRegistry.Find(Command);
-	if (!HandlerClass)
-	{
-		return FString::Printf(TEXT("Unknown command: %s"), *Command);
-	}
-
-	// Make an object of the handler class.
-	TStrongObjectPtr<UObject> HandlerObj(NewObject<UObject>(GetTransientPackage(), *HandlerClass));
-	IMCPHandler* Handler = Cast<IMCPHandler>(HandlerObj.Get());
-
-	// Populate the handler object with the request parameters.
-	HandlerOutput.Reset();
-	if (!MCPUtils::PopulateFromJson(HandlerObj->GetClass(), HandlerObj.Get(), &*Request))
-	{
-		HandlerOutput.Append(TEXT("\nUsage:\n"));
-		MCPUtils::FormatCommandHelp(*HandlerClass, HandlerOutput);
-		FString Result = HandlerOutput.ToString();
-		HandlerOutput.Reset();
-		return Result;
-	}
-
-	// Invoke the handler with log capture.
 	LogCapture.CapturedErrors.Empty();
 	LogCapture.bEnabled = true;
 	HandlerOutput.Reset();
-	Handler->Handle(HandlerOutput);
+
+	TryCallHandler(Line);
+
 	Notifier.SendNotifications();
 	LogCapture.bEnabled = false;
 	for (const FString& Msg : LogCapture.CapturedErrors)
 	{
-		HandlerOutput.Append(TEXT("LOG: "));
+		UMCPServer::Printf(TEXT("UE_LOG: %s\n"), *Msg);
-		HandlerOutput.Append(Msg);
-		HandlerOutput.Append(TEXT("\n"));
 	}
 	LogCapture.CapturedErrors.Empty();
 	FString Result = HandlerOutput.ToString();
@@ -322,6 +282,51 @@ FString UMCPServer::HandleRequest(const FString& Line)
 	return Result;
 }
 
+void UMCPServer::TryCallHandler(const FString &Line)
+{
+	// Turn the request string into a JSON tree.
+	TSharedPtr<FJsonObject> Request;
+	TSharedRef<TJsonReader<>> Reader = TJsonReaderFactory<>::Create(Line);
+	FJsonSerializer::Deserialize(Reader, Request);
+	if (!Request.IsValid())
+	{
+		UMCPServer::Printf(TEXT("Request is not valid JSON"));
+		return;
+	}
+
+	// Extract the command from the request.
+	FString Command;
+	if (!Request->TryGetStringField(TEXT("command"), Command))
+	{
+		UMCPServer::Printf(TEXT("Request does not contain 'command' parameter"));
+		return;
+	}
+	Request->RemoveField(TEXT("command"));
+
+	// Find the handler UClass for the specified command.
+	UClass** HandlerClass = MCPHandlerRegistry.Find(Command);
+	if (!HandlerClass)
+	{
+		UMCPServer::Printf(TEXT("Unknown command: %s"), *Command);
+		return;
+	}
+
+	// Make an object of the handler class.
+	TStrongObjectPtr<UObject> HandlerObj(NewObject<UObject>(GetTransientPackage(), *HandlerClass));
+	IMCPHandler* Handler = Cast<IMCPHandler>(HandlerObj.Get());
+
+	// Populate the handler object with the request parameters.
+	if (!MCPUtils::PopulateFromJson(HandlerObj->GetClass(), HandlerObj.Get(), &*Request))
+	{
+		UMCPServer::Printf(TEXT("\nUsage:\n\n"));
+		MCPUtils::FormatCommandHelp(*HandlerClass);
+		return;
+	}
+
+	// Invoke the handler.
+	Handler->Handle();
+}
+
 // ============================================================
 // Connection Maintenance
 // ============================================================

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

@@ -813,7 +813,7 @@ bool MCPUtils::ParseMaterialParameterAssociation(const FString& Str, EMaterialPa
 	return true;
 }
 
-void MCPUtils::FormatMaterialParameter(FStringBuilderBase& Result, const FMaterialParameterInfo& Info, const FMaterialParameterMetadata& Meta)
+void MCPUtils::FormatMaterialParameter(const FMaterialParameterInfo& Info, const FMaterialParameterMetadata& Meta)
 {
 	// Association prefix for layer/blend parameters.
 	FString Prefix;
@@ -825,35 +825,35 @@ void MCPUtils::FormatMaterialParameter(FStringBuilderBase& Result, const FMateri
 	switch (Meta.Value.Type)
 	{
 	case EMaterialParameterType::Scalar:
-		Result.Appendf(TEXT("  %sScalar \"%s\" = %g\n"), *Prefix, *Info.Name.ToString(), Meta.Value.AsScalar());
+		UMCPServer::Printf(TEXT("  %sScalar \"%s\" = %g\n"), *Prefix, *Info.Name.ToString(), Meta.Value.AsScalar());
 		break;
 	case EMaterialParameterType::Vector:
 	{
 		FLinearColor C = Meta.Value.AsLinearColor();
-		Result.Appendf(TEXT("  %sVector \"%s\" = (R=%.3f, G=%.3f, B=%.3f, A=%.3f)\n"),
+		UMCPServer::Printf(TEXT("  %sVector \"%s\" = (R=%.3f, G=%.3f, B=%.3f, A=%.3f)\n"),
 			*Prefix, *Info.Name.ToString(), C.R, C.G, C.B, C.A);
 		break;
 	}
 	case EMaterialParameterType::DoubleVector:
 	{
 		FVector4d V = Meta.Value.AsVector4d();
-		Result.Appendf(TEXT("  %sDoubleVector \"%s\" = (%.3f, %.3f, %.3f, %.3f)\n"),
+		UMCPServer::Printf(TEXT("  %sDoubleVector \"%s\" = (%.3f, %.3f, %.3f, %.3f)\n"),
 			*Prefix, *Info.Name.ToString(), V.X, V.Y, V.Z, V.W);
 		break;
 	}
 	case EMaterialParameterType::Texture:
 	{
 		UTexture* Tex = Cast<UTexture>(Meta.Value.AsTextureObject());
-		Result.Appendf(TEXT("  %sTexture \"%s\" = %s\n"),
+		UMCPServer::Printf(TEXT("  %sTexture \"%s\" = %s\n"),
 			*Prefix, *Info.Name.ToString(), Tex ? *MCPUtils::FormatName(Tex) : TEXT("None"));
 		break;
 	}
 	case EMaterialParameterType::StaticSwitch:
-		Result.Appendf(TEXT("  %sStaticSwitch \"%s\" = %s\n"),
+		UMCPServer::Printf(TEXT("  %sStaticSwitch \"%s\" = %s\n"),
 			*Prefix, *Info.Name.ToString(), Meta.Value.AsStaticSwitch() ? TEXT("true") : TEXT("false"));
 		break;
 	default:
-		Result.Appendf(TEXT("  %sType%d \"%s\"\n"), *Prefix, (int)Meta.Value.Type, *Info.Name.ToString());
+		UMCPServer::Printf(TEXT("  %sType%d \"%s\"\n"), *Prefix, (int)Meta.Value.Type, *Info.Name.ToString());
 		break;
 	}
 }
@@ -1398,29 +1398,29 @@ TArray<FProperty*> MCPUtils::SearchProperties(UObject* Obj, const FString& Query
 // FormatCommandHelp — verbose description of one handler command
 // ============================================================
 
-void MCPUtils::FormatCommandHelp(UClass* HandlerClass, FStringBuilderBase& Result)
+void MCPUtils::FormatCommandHelp(UClass* HandlerClass)
 {
 	const IMCPHandler* Handler = Cast<IMCPHandler>(HandlerClass->GetDefaultObject());
 	if (!Handler) return;
 
 	FString ToolName = GetHandlerName(HandlerClass);
 
-	Result.Append(TEXT("\n"));
+	UMCPServer::Print(TEXT("\n"));
-	Result.Append(WrapText(Handler->GetDescription(), 80, TEXT("// ")));
+	UMCPServer::Print(WrapText(Handler->GetDescription(), 80, TEXT("// ")));
-	Result.Append(TEXT("\n"));
+	UMCPServer::Print(TEXT("\n"));
 
 	// Command signature line
-	Result.Append(ToolName);
+	UMCPServer::Print(ToolName);
-	Result.Append(TEXT("("));
+	UMCPServer::Print(TEXT("("));
 	bool bFirst = true;
 	for (TFieldIterator<FProperty> PropIt(HandlerClass, EFieldIterationFlags::None); PropIt; ++PropIt)
 	{
-		if (!bFirst) Result.Append(TEXT(","));
+		if (!bFirst) UMCPServer::Print(TEXT(","));
 		bFirst = false;
-		if (PropIt->HasMetaData(TEXT("Optional"))) Result.Append(TEXT("?"));
+		if (PropIt->HasMetaData(TEXT("Optional"))) UMCPServer::Print(TEXT("?"));
-		Result.Append(PropertyNameToJsonKey(PropIt->GetName()));
+		UMCPServer::Print(PropertyNameToJsonKey(PropIt->GetName()));
 	}
-	Result.Append(TEXT(")\n"));
+	UMCPServer::Print(TEXT(")\n"));
 
 	// parameter details
 	for (TFieldIterator<FProperty> PropIt(HandlerClass, EFieldIterationFlags::None); PropIt; ++PropIt)
@@ -1431,10 +1431,10 @@ void MCPUtils::FormatCommandHelp(UClass* HandlerClass, FStringBuilderBase& Resul
 		bool bOptional = Prop->HasMetaData(TEXT("Optional"));
 		const FString& Desc = Prop->GetMetaData(TEXT("Description"));
 
-		Result.Appendf(TEXT("    %s %s%s"),
+		UMCPServer::Printf(TEXT("    %s %s%s"),
 			*Type, *Name, bOptional ? TEXT(" (optional)") : TEXT(""));
 		if (!Desc.IsEmpty())
-			Result.Appendf(TEXT(" — %s"), *Desc);
+			UMCPServer::Printf(TEXT(" — %s"), *Desc);
-		Result.Append(TEXT("\n"));
+		UMCPServer::Print(TEXT("\n"));
 	}
 }

Plugins/BlueprintMCP/Source/BlueprintMCP/Public/MCPHandler.h

@@ -51,5 +51,5 @@ public:
 	virtual FString GetDescription() const = 0;
 
 	// Called after parameter fields have been populated from JSON.
-	virtual void Handle(FStringBuilderBase& Result) {}
+	virtual void Handle() {}
 };

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

@@ -53,6 +53,7 @@ public:
 
 	/** Print text to the handler output buffer. */
 	static void Print(const TCHAR* Text) { GMCPServer->HandlerOutput.Append(Text); }
+	static void Print(const FString& Text) { GMCPServer->HandlerOutput.Append(Text); }
 
 	/** Print formatted text to the handler output buffer. */
 	template <typename FmtType, typename... ArgTypes>
@@ -79,6 +80,7 @@ private:
 
 	// Handle a complete JSON line and return the response JSON
 	FString HandleRequest(const FString& Line);
+	void TryCallHandler(const FString &Line);
 
 	// ----- TCP server -----
 	FSocket* ListenSocket = nullptr;

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

@@ -162,7 +162,7 @@ public:
 	// ----- Material Parameters -----
 	static TMap<FMaterialParameterInfo, FMaterialParameterMetadata> GetMaterialParameters(UMaterialInterface* Material);
 	static bool ParseMaterialParameterAssociation(const FString& Str, EMaterialParameterAssociation& OutAssociation);
-	static void FormatMaterialParameter(FStringBuilderBase& Result, const FMaterialParameterInfo& Info, const FMaterialParameterMetadata& Meta);
+	static void FormatMaterialParameter(const FMaterialParameterInfo& Info, const FMaterialParameterMetadata& Meta);
 
 	// ----- Editable template -----
 	static TArray<FProperty*> SearchProperties(UObject* Obj, const FString& Query, EPropertyFlags Flags, bool bLocal);
@@ -183,7 +183,7 @@ public:
 	static TArray<UClass*> CollectHandlerClasses();
 	static FString GetHandlerName(UClass* HandlerClass);
 	static FString GetHandlerGroup(UClass* HandlerClass);
-	static void FormatCommandHelp(UClass* HandlerClass, FStringBuilderBase& Result);
+	static void FormatCommandHelp(UClass* HandlerClass);
 
 
 private: