MCP Backup Restore and remove undo

Plugins/BlueprintMCP/Source/BlueprintMCP/Private/MCPHandlers_AssetMutation.h

@@ -12,6 +12,7 @@
 #include "AssetRegistry/IAssetRegistry.h"
 #include "AssetToolsModule.h"
 #include "IAssetTools.h"
+#include "FileHelpers.h"
 #include "MCPHandlers_AssetMutation.generated.h"
 
 // ---------------------------------------------------------------------------
@@ -241,3 +242,97 @@ public:
 		}
 	}
 };
+
+// ---------------------------------------------------------------------------
+// ---------------------------------------------------------------------------
+// ---------------------------------------------------------------------------
+
+UCLASS(meta=(ToolName="backup_asset"))
+class UMCPHandler_BackupAsset : public UObject, public IMCPHandler
+{
+	GENERATED_BODY()
+
+public:
+	UPROPERTY(meta=(Description="Full package path of the asset (e.g. /Game/Widgets/WB_Hotkeys)"))
+	FString AssetPath;
+
+	virtual FString GetDescription() const override
+	{
+		return TEXT("Copy an asset's .uasset file to a .uasset.bak backup.");
+	}
+
+	virtual void Handle(const FJsonObject* Json, FJsonObject* Result) override
+	{
+		FString Filename = FPaths::ConvertRelativePathToFull(
+			FPackageName::LongPackageNameToFilename(AssetPath, FPackageName::GetAssetPackageExtension()));
+
+		if (!IFileManager::Get().FileExists(*Filename))
+		{
+			return MCPUtils::MakeErrorJson(Result, FString::Printf(TEXT("Asset file not found: %s"), *Filename));
+		}
+
+		FString BackupFilename = Filename + TEXT(".bak");
+		uint32 CopyResult = IFileManager::Get().Copy(*BackupFilename, *Filename, true);
+		if (CopyResult != COPY_OK)
+		{
+			return MCPUtils::MakeErrorJson(Result, FString::Printf(TEXT("Failed to back up %s"), *Filename));
+		}
+
+		Result->SetStringField(TEXT("backupFile"), BackupFilename);
+	}
+};
+
+// ---------------------------------------------------------------------------
+// ---------------------------------------------------------------------------
+// ---------------------------------------------------------------------------
+
+UCLASS(meta=(ToolName="restore_asset"))
+class UMCPHandler_RestoreAsset : public UObject, public IMCPHandler
+{
+	GENERATED_BODY()
+
+public:
+	UPROPERTY(meta=(Description="Full package path of the asset (e.g. /Game/Widgets/WB_Hotkeys)"))
+	FString AssetPath;
+
+	virtual FString GetDescription() const override
+	{
+		return TEXT("Restore a .uasset file from its .uasset.bak backup, reloading it in the editor.");
+	}
+
+	virtual void Handle(const FJsonObject* Json, FJsonObject* Result) override
+	{
+		FString Filename = FPaths::ConvertRelativePathToFull(
+			FPackageName::LongPackageNameToFilename(AssetPath, FPackageName::GetAssetPackageExtension()));
+		FString BackupFilename = Filename + TEXT(".bak");
+
+		if (!IFileManager::Get().FileExists(*BackupFilename))
+		{
+			return MCPUtils::MakeErrorJson(Result, FString::Printf(TEXT("Backup file not found: %s"), *BackupFilename));
+		}
+
+		// Release file handles if the package is loaded
+		UPackage* Package = FindPackage(nullptr, *AssetPath);
+		if (Package)
+		{
+			ResetLoaders(Package);
+		}
+
+		// Copy backup over the original
+		uint32 CopyResult = IFileManager::Get().Copy(*Filename, *BackupFilename, true);
+		if (CopyResult != COPY_OK)
+		{
+			return MCPUtils::MakeErrorJson(Result, FString::Printf(TEXT("Failed to restore %s"), *Filename));
+		}
+
+		// Reload the package if it was loaded
+		if (Package)
+		{
+			bool bReloaded = false;
+			FText ErrorMessage;
+			UEditorLoadingAndSavingUtils::ReloadPackages({Package}, bReloaded, ErrorMessage, EReloadPackagesInteractionMode::AssumePositive);
+		}
+
+		Result->SetStringField(TEXT("restoredFrom"), BackupFilename);
+	}
+};

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

@@ -253,23 +253,12 @@ void FMCPServer::DispatchToolCall(const FString& ToolName, const FJsonObject* Pa
 {
 	if (UClass** HandlerClass = MCPHandlerRegistry.Find(ToolName))
 	{
-		const bool bIsMutation = MutationEndpoints.Contains(ToolName);
-		if (bIsMutation && GEditor)
-		{
-			GEditor->BeginTransaction(FText::FromString(FString::Printf(TEXT("BlueprintMCP: %s"), *ToolName)));
-		}
-
 		TStrongObjectPtr<UObject> HandlerObj(NewObject<UObject>(GetTransientPackage(), *HandlerClass));
 		IMCPHandler* Handler = Cast<IMCPHandler>(HandlerObj.Get());
 		if (MCPUtils::PopulateFromJson(HandlerObj->GetClass(), HandlerObj.Get(), Params, Result))
 		{
 			Handler->Handle(Params, Result);
 		}
-
-		if (bIsMutation && GEditor)
-		{
-			GEditor->EndTransaction();
-		}
 	}
 	else
 	{
@@ -316,7 +305,6 @@ bool FMCPServer::Start(int32 InPort, bool bEditorMode)
 
 	// Register handlers
 	BuildMCPHandlerRegistry();
-	RegisterHandlers();
 
 	// Create TCP listen socket
 	ISocketSubsystem* SocketSub = ISocketSubsystem::Get(PLATFORM_SOCKETSUBSYSTEM);
@@ -535,65 +523,9 @@ bool FMCPServer::ProcessOneRequest()
 }
 
 // ============================================================
-// RegisterHandlers / BuildMCPHandlerRegistry
+// BuildMCPHandlerRegistry
 // ============================================================
 
-void FMCPServer::RegisterHandlers()
-{
-	// Mutation endpoints — wrapped in undo transactions by DispatchToolCall()
-	MutationEndpoints = {
-		TEXT("replace_function_calls_in_blueprint"),
-		TEXT("change_blueprint_variable_type"),
-		TEXT("change_function_parameter_type"),
-		TEXT("remove_function_parameter"),
-		TEXT("delete_asset"),
-		TEXT("connect_blueprint_pins"),
-		TEXT("disconnect_blueprint_pins"),
-		TEXT("refresh_all_nodes_in_graph"),
-		TEXT("set_pin_default_values"),
-		TEXT("set_node_positions"),
-		TEXT("change_struct_node_type"),
-		TEXT("delete_node_from_graph"),
-		TEXT("duplicate_nodes_in_graph"),
-		TEXT("spawn_nodes_in_graph"),
-		TEXT("set_node_comment"),
-		TEXT("rename_asset"),
-		TEXT("reparent_blueprint"),
-		TEXT("set_class_default_value"),
-		TEXT("create_blueprint_asset"),
-		TEXT("create_blueprint_graph"),
-		TEXT("delete_blueprint_graph"),
-		TEXT("rename_blueprint_graph"),
-		TEXT("add_blueprint_variable"),
-		TEXT("remove_blueprint_variable"),
-		TEXT("set_blueprint_variable_metadata"),
-		TEXT("add_blueprint_interface"),
-		TEXT("remove_blueprint_interface"),
-		TEXT("add_event_dispatcher"),
-		TEXT("add_function_parameter"),
-		TEXT("add_blueprint_component"),
-		TEXT("remove_blueprint_component"),
-		TEXT("create_material_asset"),
-		TEXT("set_material_property"),
-		TEXT("add_material_expression"),
-		TEXT("delete_material_expression"),
-		TEXT("connect_material_expression_pins"),
-		TEXT("disconnect_material_expression_pin"),
-		TEXT("set_material_expression_property"),
-		TEXT("set_material_expression_position"),
-		TEXT("create_material_instance_asset"),
-		TEXT("set_material_instance_parameter"),
-		TEXT("reparent_material_instance"),
-		TEXT("create_material_function_asset"),
-		TEXT("add_anim_state_to_machine"),
-		TEXT("remove_anim_state_from_machine"),
-		TEXT("add_anim_state_transition"),
-		TEXT("set_anim_transition_rule"),
-		TEXT("set_anim_state_animation"),
-	};
-
-}
-
 void FMCPServer::BuildMCPHandlerRegistry()
 {
 	for (TObjectIterator<UClass> It; It; ++It)

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

@@ -51,8 +51,6 @@ public:
 private:
 	// ----- Tool dispatch -----
 	TMap<FString, UClass*> MCPHandlerRegistry;         // tool name -> UMCPHandler subclass
-	TSet<FString> MutationEndpoints;
-	void RegisterHandlers();
 	void BuildMCPHandlerRegistry();
 
 	// Dispatch a tool call to the appropriate handler