More work on handlers

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

@@ -73,7 +73,7 @@ public:
 		UBlendSpace* BS = Assets.Object();
 
 		// Set axis parameters
-		BS->PreEditChange(nullptr);
+		MCPUtils::PreEdit({BS});
 
 		const FBlendParameter& ParamX = BS->GetBlendParameter(0);
 		const FBlendParameter& ParamY = BS->GetBlendParameter(1);
@@ -126,10 +126,9 @@ public:
 		}
 
 		BS->ValidateSampleData();
-		BS->PostEditChange();
+		MCPUtils::PostEdit({BS});
 
 		// Save
-		BS->MarkPackageDirty();
 		bool bSaved = MCPUtils::SaveGenericPackage(BS);
 
 		Result.Appendf(TEXT("Set %d samples on %s\n"), SamplesSet, *MCPUtils::FormatName(BS));

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

@@ -70,7 +70,6 @@ public:
 		// Set skeleton.
 		NewBS->SetSkeleton(SkeletonObj);
 
-		// Mark dirty and save.
 		NewBS->MarkPackageDirty();
 		bool bSaved = MCPUtils::SaveGenericPackage(NewBS);
 

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

@@ -69,6 +69,8 @@ public:
 			}
 		}
 
+		F.PreEdit();
+
 		if (GraphType == TEXT("function"))
 		{
 			UEdGraph* NewGraph = FBlueprintEditorUtils::CreateNewGraph(BP, FName(*Graph),
@@ -114,7 +116,7 @@ public:
 			Result.Appendf(TEXT("Created custom event: %s\n"), *MCPUtils::FormatName(NewEvent));
 		}
 
-		FBlueprintEditorUtils::MarkBlueprintAsStructurallyModified(BP);
+		F.PostEdit();
 		MCPUtils::SaveBlueprintPackage(BP);
 	}
 };

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

@@ -85,8 +85,9 @@ public:
 
 		// Remove the graph
 		FString GraphName = MCPUtils::FormatName(TargetGraph);
+		F.PreEdit();
 		FBlueprintEditorUtils::RemoveGraph(BP, TargetGraph, EGraphRemoveFlags::Default);
-		FBlueprintEditorUtils::MarkBlueprintAsStructurallyModified(BP);
+		F.PostEdit();
 		bool bSaved = MCPUtils::SaveBlueprintPackage(BP);
 
 		Result.Appendf(TEXT("Deleted %s graph %s\n"), *GraphType, *GraphName);

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

@@ -73,8 +73,9 @@ public:
 			}
 		}
 
+		F.PreEdit();
 		FBlueprintEditorUtils::RenameGraph(TargetGraph, NewName);
-		FBlueprintEditorUtils::MarkBlueprintAsStructurallyModified(BP);
+		F.PostEdit();
 		MCPUtils::SaveBlueprintPackage(BP);
 
 		Result.Appendf(TEXT("Renamed to %s %s\n"),

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

@@ -8,7 +8,6 @@
 #include "Engine/SimpleConstructionScript.h"
 #include "Engine/SCS_Node.h"
 #include "Components/ActorComponent.h"
-#include "Kismet2/BlueprintEditorUtils.h"
 #include "Blueprint_AddComponent.generated.h"
 
 
@@ -107,6 +106,7 @@ public:
 		}
 
 		// Create the SCS node
+		MCPUtils::PreEdit({BP});
 		USCS_Node* NewNode = SCS->CreateNode(ComponentClassObj, FName(*Component));
 		if (!NewNode)
 		{
@@ -126,7 +126,7 @@ public:
 			SCS->AddNode(NewNode);
 		}
 
-		FBlueprintEditorUtils::MarkBlueprintAsStructurallyModified(BP);
+		MCPUtils::PostEdit({BP});
 		bool bSaved = MCPUtils::SaveBlueprintPackage(BP);
 
 		Result.Appendf(TEXT("Added component %s (%s)"),

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

@@ -75,6 +75,7 @@ public:
 		}
 
 		// Add a member variable with PC_MCDelegate pin type
+		F.PreEdit();
 		FEdGraphPinType DelegateType;
 		DelegateType.PinCategory = UEdGraphSchema_K2::PC_MCDelegate;
 		if (!FBlueprintEditorUtils::AddMemberVariable(BP, DispatcherFName, DelegateType))
@@ -115,7 +116,7 @@ public:
 
 			if (!EntryNode)
 			{
-				FBlueprintEditorUtils::MarkBlueprintAsStructurallyModified(BP);
+				F.PostEdit();
 				MCPUtils::SaveBlueprintPackage(BP);
 				Result.Append(TEXT("Error: Event dispatcher created but entry node not found — parameters could not be added.\n"));
 				return;
@@ -136,7 +137,7 @@ public:
 			}
 		}
 
-		FBlueprintEditorUtils::MarkBlueprintAsStructurallyModified(BP);
+		F.PostEdit();
 		MCPUtils::SaveBlueprintPackage(BP);
 
 		Result.Appendf(TEXT("Created event dispatcher '%s'"), *DispatcherName);

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

@@ -133,9 +133,9 @@ public:
 		}
 
 		// Add the parameter pin (EGPD_Output on entry = input to callers)
+		MCPUtils::PreEdit({BP});
 		EntryNode->CreateUserDefinedPin(FName(*ParamName), PinType, EGPD_Output);
-
-		FBlueprintEditorUtils::MarkBlueprintAsStructurallyModified(BP);
+		MCPUtils::PostEdit({BP});
 		bool bSaved = MCPUtils::SaveBlueprintPackage(BP);
 
 		Result.Appendf(TEXT("Added %s parameter '%s' to %s '%s'%s\n"),

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

@@ -55,6 +55,7 @@ public:
 		}
 
 		FTopLevelAssetPath InterfacePath = InterfaceClass->GetClassPathName();
+		MCPUtils::PreEdit({BP});
 		bool bAdded = FBlueprintEditorUtils::ImplementNewInterface(BP, InterfacePath);
 		if (!bAdded)
 		{
@@ -65,7 +66,7 @@ public:
 		}
 
 		// Collect stub function graph names from the newly added interface entry
-		FBlueprintEditorUtils::MarkBlueprintAsStructurallyModified(BP);
+		MCPUtils::PostEdit({BP});
 
 		Result.Appendf(TEXT("Added interface %s\n"), *MCPUtils::FormatName(InterfaceClass));
 		Result.Appendf(TEXT("Function stubs:\n"));

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

@@ -69,6 +69,7 @@ public:
 			PinType.ContainerType = EPinContainerType::Array;
 
 		// Add the variable
+		MCPUtils::PreEdit({BP});
 		if (!FBlueprintEditorUtils::AddMemberVariable(BP, VarFName, PinType, DefaultValue))
 		{
 			MCPErrorCallback(Result).SetError(FString::Printf(
@@ -79,7 +80,7 @@ public:
 		if (!Category.IsEmpty())
 			FBlueprintEditorUtils::SetBlueprintVariableCategory(BP, VarFName, nullptr, FText::FromString(Category));
 
-		FBlueprintEditorUtils::MarkBlueprintAsStructurallyModified(BP);
+		MCPUtils::PostEdit({BP});
 		bool bSaved = MCPUtils::SaveBlueprintPackage(BP);
 
 		Result.Appendf(TEXT("Added %s %s to %s\n"),

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

@@ -135,7 +135,8 @@ public:
 			return;
 		}
 
-		// Apply the type change
+		// Apply the type change (PreEdit/PostEdit on the node itself, not the BP —
+		// MCPUtils::PreEdit/PostEdit operates at BP level, not node level)
 		EntryNode->PreEditChange(nullptr);
 		(*FoundPinInfo)->PinType = NewPinType;
 		EntryNode->PostEditChange();

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

@@ -9,7 +9,6 @@
 #include "EdGraph/EdGraphPin.h"
 #include "K2Node_VariableGet.h"
 #include "K2Node_VariableSet.h"
-#include "Kismet2/BlueprintEditorUtils.h"
 #include "Blueprint_ChangeVariableType.generated.h"
 
 
@@ -129,9 +128,9 @@ public:
 		}
 
 		// Apply the type change
-		BP->PreEditChange(nullptr);
+		F.PreEdit();
 		Found->VarType = NewPinType;
-		BP->PostEditChange();
+		F.PostEdit();
 
 		bool bSaved = MCPUtils::SaveBlueprintPackage(BP);
 		Result.Appendf(TEXT("Changed %s to %s.%s\n"),

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

@@ -42,6 +42,7 @@ public:
 		int32 NodeCount = MCPUtils::AllNodes(BP).Num();
 
 		// Refresh all nodes
+		MCPUtils::PreEdit({BP});
 		FBlueprintEditorUtils::RefreshAllNodes(BP);
 
 		// Remove orphaned pins from all nodes
@@ -61,7 +62,7 @@ public:
 		}
 
 		// Mark as modified and recompile after orphan removal
-		FBlueprintEditorUtils::MarkBlueprintAsStructurallyModified(BP);
+		MCPUtils::PostEdit({BP});
 
 		// Summary
 		Result.Appendf(TEXT("Refreshed %s: %d graphs, %d nodes"), *MCPUtils::FormatName(BP), GraphCount, NodeCount);

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

@@ -7,7 +7,6 @@
 #include "Engine/Blueprint.h"
 #include "Engine/SimpleConstructionScript.h"
 #include "Engine/SCS_Node.h"
-#include "Kismet2/BlueprintEditorUtils.h"
 #include "Blueprint_RemoveComponent.generated.h"
 
 
@@ -84,9 +83,10 @@ public:
 		FString RemovedName = MCPUtils::FormatName(NodeToRemove->ComponentTemplate);
 
 		// Remove the node (promotes children to parent if it has any — but we've guarded root above)
+		F.PreEdit();
 		SCS->RemoveNodeAndPromoteChildren(NodeToRemove);
+		F.PostEdit();
 
-		FBlueprintEditorUtils::MarkBlueprintAsStructurallyModified(BP);
 		bool bSaved = MCPUtils::SaveBlueprintPackage(BP);
 
 		Result.Appendf(TEXT("Removed component %s.%s\n"),

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

@@ -65,8 +65,9 @@ public:
 		}
 
 		FTopLevelAssetPath InterfacePath = FoundInterface->GetClassPathName();
+		MCPUtils::PreEdit({BP});
 		FBlueprintEditorUtils::RemoveInterface(BP, InterfacePath, PreserveFunctions);
-		FBlueprintEditorUtils::MarkBlueprintAsStructurallyModified(BP);
+		MCPUtils::PostEdit({BP});
 
 		Result.Appendf(TEXT("Removed interface %s\n"), *MCPUtils::FormatName(FoundInterface));
 		if (PreserveFunctions)

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

@@ -62,8 +62,9 @@ public:
 		FName VarFName = Found->VarName;
 
 		// RemoveMemberVariable also cleans up Get/Set nodes
+		F.PreEdit();
 		FBlueprintEditorUtils::RemoveMemberVariable(BP, VarFName);
-		FBlueprintEditorUtils::MarkBlueprintAsStructurallyModified(BP);
+		F.PostEdit();
 
 		bool bSaved = MCPUtils::SaveBlueprintPackage(BP);
 		Result.Appendf(TEXT("Removed variable %s from %s.%s\n"),

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

@@ -61,9 +61,9 @@ public:
 		}
 
 		// Perform reparent
-		BP->PreEditChange(nullptr);
+		MCPUtils::PreEdit({BP});
 		BP->ParentClass = NewParentClassObj;
-		BP->PostEditChange();
+		MCPUtils::PostEdit({BP});
 		FBlueprintEditorUtils::RefreshAllNodes(BP);
 		FKismetEditorUtilities::CompileBlueprint(BP);
 		bool bSaved = MCPUtils::SaveBlueprintPackage(BP);

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Blueprint_SetVariableMetadata.h

@@ -1,191 +0,0 @@
-#pragma once
-
-#include "CoreMinimal.h"
-#include "MCPHandler.h"
-#include "MCPFetcher.h"
-#include "MCPUtils.h"
-#include "Engine/Blueprint.h"
-#include "Kismet2/BlueprintEditorUtils.h"
-#include "Blueprint_SetVariableMetadata.generated.h"
-
-
-// ---------------------------------------------------------------------------
-// ---------------------------------------------------------------------------
-// ---------------------------------------------------------------------------
-
-UCLASS()
-class UMCP_Blueprint_SetVariableMetadata : public UObject, public IMCPHandler
-{
-	GENERATED_BODY()
-
-public:
-	UPROPERTY(meta=(Description="Blueprint name or package path"))
-	FString Blueprint;
-
-	UPROPERTY(meta=(Description="Name of the variable to modify"))
-	FString Variable;
-
-	UPROPERTY(meta=(Optional, Description="Category to assign the variable to"))
-	FString Category;
-
-	UPROPERTY(meta=(Optional, Description="Tooltip text for the variable"))
-	FString Tooltip;
-
-	UPROPERTY(meta=(Optional, Description="Replication mode: none, replicated, or repNotify"))
-	FString Replication;
-
-	UPROPERTY(meta=(Optional, Description="If true, expose this variable on spawn"))
-	bool ExposeOnSpawn = false;
-
-	UPROPERTY(meta=(Optional, Description="If true, mark the variable as private"))
-	bool IsPrivate = false;
-
-	UPROPERTY(meta=(Optional, Description="Editability mode: editAnywhere, editDefaultsOnly, editInstanceOnly, or none"))
-	FString Editability;
-
-	virtual FString GetDescription() const override
-	{
-		return TEXT("Set variable metadata properties such as category, tooltip, "
-			"replication, editability, and visibility flags.");
-	}
-
-	virtual void Handle(const FJsonObject* Json, FStringBuilderBase& Result) override
-	{
-		MCPFetcher F(Result);
-		UBlueprint* BP = F.Walk(Blueprint).Cast<UBlueprint>();
-		if (!BP) return;
-
-		// Find the variable using Identifies for consistent name matching
-		FBPVariableDescription* VarDesc = nullptr;
-		for (FBPVariableDescription& Var : BP->NewVariables)
-		{
-			if (MCPUtils::FormatName(Var) == Variable ||
-				Var.VarName.ToString().Equals(Variable, ESearchCase::IgnoreCase))
-			{
-				VarDesc = &Var;
-				break;
-			}
-		}
-
-		if (!VarDesc)
-		{
-			Result.Appendf(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));
-			}
-			return;
-		}
-
-		FName VarFName = VarDesc->VarName;
-		int32 ChangeCount = 0;
-
-		// Category
-		if (Json->HasField(TEXT("category")))
-		{
-			VarDesc->Category = FText::FromString(Category);
-			FBlueprintEditorUtils::SetBlueprintVariableCategory(BP, VarFName, nullptr, FText::FromString(Category));
-			Result.Appendf(TEXT("Set category to '%s'.\n"), *Category);
-			ChangeCount++;
-		}
-
-		// Tooltip
-		if (Json->HasField(TEXT("tooltip")))
-		{
-			FBlueprintEditorUtils::SetBlueprintVariableMetaData(BP, VarFName, nullptr, TEXT("tooltip"), Tooltip);
-			Result.Appendf(TEXT("Set tooltip to '%s'.\n"), *Tooltip);
-			ChangeCount++;
-		}
-
-		// Replication
-		if (Json->HasField(TEXT("replication")))
-		{
-			if (Replication == TEXT("none"))
-			{
-				VarDesc->PropertyFlags &= ~CPF_Net;
-				VarDesc->PropertyFlags &= ~CPF_RepNotify;
-				VarDesc->RepNotifyFunc = NAME_None;
-			}
-			else if (Replication == TEXT("replicated"))
-			{
-				VarDesc->PropertyFlags |= CPF_Net;
-				VarDesc->PropertyFlags &= ~CPF_RepNotify;
-				VarDesc->RepNotifyFunc = NAME_None;
-			}
-			else if (Replication == TEXT("repNotify"))
-			{
-				VarDesc->PropertyFlags |= CPF_Net | CPF_RepNotify;
-				VarDesc->RepNotifyFunc = FName(*FString::Printf(TEXT("OnRep_%s"), *Variable));
-			}
-			else
-			{
-				Result.Appendf(TEXT("ERROR: Invalid replication value '%s'. Valid: none, replicated, repNotify\n"), *Replication);
-				return;
-			}
-			Result.Appendf(TEXT("Set replication to '%s'.\n"), *Replication);
-			ChangeCount++;
-		}
-
-		// ExposeOnSpawn
-		if (Json->HasField(TEXT("exposeOnSpawn")))
-		{
-			if (ExposeOnSpawn)
-				VarDesc->PropertyFlags |= CPF_ExposeOnSpawn;
-			else
-				VarDesc->PropertyFlags &= ~CPF_ExposeOnSpawn;
-			Result.Appendf(TEXT("Set exposeOnSpawn to %s.\n"), ExposeOnSpawn ? TEXT("true") : TEXT("false"));
-			ChangeCount++;
-		}
-
-		// isPrivate
-		if (Json->HasField(TEXT("isPrivate")))
-		{
-			FBlueprintEditorUtils::SetBlueprintVariableMetaData(BP, VarFName, nullptr,
-				TEXT("BlueprintPrivate"), IsPrivate ? TEXT("true") : TEXT("false"));
-			Result.Appendf(TEXT("Set isPrivate to %s.\n"), IsPrivate ? TEXT("true") : TEXT("false"));
-			ChangeCount++;
-		}
-
-		// Editability
-		if (Json->HasField(TEXT("editability")))
-		{
-			VarDesc->PropertyFlags &= ~(CPF_Edit | CPF_DisableEditOnInstance | CPF_DisableEditOnTemplate);
-
-			if (Editability == TEXT("editAnywhere"))
-			{
-				VarDesc->PropertyFlags |= CPF_Edit;
-			}
-			else if (Editability == TEXT("editDefaultsOnly"))
-			{
-				VarDesc->PropertyFlags |= CPF_Edit | CPF_DisableEditOnInstance;
-			}
-			else if (Editability == TEXT("editInstanceOnly"))
-			{
-				VarDesc->PropertyFlags |= CPF_Edit | CPF_DisableEditOnTemplate;
-			}
-			else if (Editability != TEXT("none"))
-			{
-				Result.Appendf(TEXT("ERROR: Invalid editability value '%s'. Valid: editAnywhere, editDefaultsOnly, editInstanceOnly, none\n"), *Editability);
-				return;
-			}
-			Result.Appendf(TEXT("Set editability to '%s'.\n"), *Editability);
-			ChangeCount++;
-		}
-
-		if (ChangeCount == 0)
-		{
-			Result.Append(TEXT("ERROR: No metadata fields specified. Provide at least one of: category, tooltip, replication, exposeOnSpawn, isPrivate, editability\n"));
-			return;
-		}
-
-		BP->PreEditChange(nullptr);
-		BP->PostEditChange();
-		FBlueprintEditorUtils::MarkBlueprintAsStructurallyModified(BP);
-		bool bSaved = MCPUtils::SaveBlueprintPackage(BP);
-
-		Result.Appendf(TEXT("Updated %d field(s) on %s in %s.%s\n"),
-			ChangeCount, *VarFName.ToString(), *MCPUtils::FormatName(BP),
-			bSaved ? TEXT("") : TEXT(" WARNING: save failed."));
-	}
-};

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

@@ -4,11 +4,9 @@
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
-#include "Engine/Blueprint.h"
 #include "EdGraph/EdGraph.h"
 #include "EdGraph/EdGraphNode.h"
 #include "EdGraph/EdGraphSchema.h"
-#include "Kismet2/BlueprintEditorUtils.h"
 #include "GraphNode_Create.generated.h"
 
 
@@ -57,6 +55,7 @@ public:
 		UEdGraph* TargetGraph = F.Walk(Graph).Cast<UEdGraph>();
 		if (!TargetGraph) return;
 
+		F.PreEdit();
 		int32 SuccessCount = 0;
 		int32 TotalCount = Nodes.Array.Num();
 
@@ -98,16 +97,7 @@ public:
 			SuccessCount++;
 		}
 
-		// Mark the owning asset as modified
-		UBlueprint* BP = Cast<UBlueprint>(TargetGraph->GetOuter());
-		if (BP)
-			FBlueprintEditorUtils::MarkBlueprintAsStructurallyModified(BP);
-
-		TargetGraph->NotifyGraphChanged();
-
-		UObject* Outer = TargetGraph->GetOuter();
-		if (Outer)
-			Outer->MarkPackageDirty();
+		F.PostEdit();
 
 		Result.Appendf(TEXT("Spawned %d/%d nodes.\n"), SuccessCount, TotalCount);
 	}

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

@@ -5,10 +5,6 @@
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
 #include "EdGraph/EdGraphNode.h"
-#include "K2Node_Event.h"
-#include "K2Node_CustomEvent.h"
-#include "K2Node_FunctionEntry.h"
-#include "Kismet2/BlueprintEditorUtils.h"
 #include "GraphNode_Delete.generated.h"
 
 
@@ -27,8 +23,8 @@ public:
 
 	virtual FString GetDescription() const override
 	{
-		return TEXT("Delete a node from a Blueprint graph. "
-			"Cannot delete entry nodes (FunctionEntry, Event, CustomEvent).");
+		return TEXT("Delete a node from a graph. "
+			"Cannot delete undeletable nodes (entry points, root nodes, etc).");
 	}
 
 	virtual void Handle(const FJsonObject* Json, FStringBuilderBase& Result) override
@@ -38,42 +34,21 @@ public:
 		if (!FoundNode) return;
 
 		UEdGraph* Graph = FoundNode->GetGraph();
-		UBlueprint* BP = FBlueprintEditorUtils::FindBlueprintForNodeChecked(FoundNode);
-
-		// Protect root/entry nodes — deleting these leaves the graph in an invalid
-		// state with no root node, causing compiler errors that can't be fixed
-		// without recreating the entire function/event.
-		MCPErrorCallback Error(Result);
 		FString NodeTitle = MCPUtils::FormatName(FoundNode);
 		FString GraphName = MCPUtils::FormatName(Graph);
 
-		if (Cast<UK2Node_FunctionEntry>(FoundNode))
+		if (!FoundNode->CanUserDeleteNode())
 		{
+			MCPErrorCallback Error(Result);
 			return Error.SetError(FString::Printf(
-				TEXT("Cannot delete FunctionEntry node '%s' in graph '%s'. ")
-				TEXT("This is the root node of the function — removing it would leave an empty, uncompilable graph. ")
-				TEXT("To remove the entire function, delete it from the Blueprint editor."),
-				*NodeTitle, *GraphName));
-		}
-		if (Cast<UK2Node_Event>(FoundNode))
-		{
-			return Error.SetError(FString::Printf(
-				TEXT("Cannot delete event entry node '%s' in graph '%s'. ")
-				TEXT("This is the root node of the event handler — removing it would leave an empty, uncompilable graph."),
-				*NodeTitle, *GraphName));
-		}
-		if (Cast<UK2Node_CustomEvent>(FoundNode))
-		{
-			return Error.SetError(FString::Printf(
-				TEXT("Cannot delete CustomEvent entry node '%s' in graph '%s'. ")
-				TEXT("This is the root node of the custom event — removing it would leave an empty, uncompilable graph."),
+				TEXT("Cannot delete node '%s' in graph '%s' — it is not deletable."),
 				*NodeTitle, *GraphName));
 		}
 
+		F.PreEdit();
 		FoundNode->BreakAllNodeLinks();
 		Graph->RemoveNode(FoundNode);
-
-		FBlueprintEditorUtils::MarkBlueprintAsStructurallyModified(BP);
+		F.PostEdit();
 
 		Result.Appendf(TEXT("Deleted node '%s' from graph '%s'.\n"), *NodeTitle, *GraphName);
 	}

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

@@ -4,11 +4,9 @@
 #include "MCPHandler.h"
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
-#include "Engine/Blueprint.h"
 #include "EdGraph/EdGraph.h"
 #include "EdGraph/EdGraphNode.h"
 #include "EdGraph/EdGraphPin.h"
-#include "Kismet2/BlueprintEditorUtils.h"
 #include "GraphNode_Duplicate.generated.h"
 
 
@@ -77,6 +75,7 @@ public:
 
 		if (SourceNodes.Num() == 0) return;
 
+		F.PreEdit();
 		// Duplicate each node
 		for (UEdGraphNode* SourceNode : SourceNodes)
 		{
@@ -101,8 +100,6 @@ public:
 			Result.Appendf(TEXT("Duplicated: %s -> %s\n"), *MCPUtils::FormatName(SourceNode), *MCPUtils::FormatName(NewNode));
 		}
 
-		UBlueprint* BP = Cast<UBlueprint>(TargetGraph->GetOuter());
-		if (BP)
-			FBlueprintEditorUtils::MarkBlueprintAsStructurallyModified(BP);
+		F.PostEdit();
 	}
 };

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

@@ -5,7 +5,6 @@
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
 #include "EdGraph/EdGraphNode.h"
-#include "Kismet2/BlueprintEditorUtils.h"
 #include "GraphNode_SetComment.generated.h"
 
 
@@ -36,6 +35,8 @@ public:
 		UEdGraphNode* FoundNode = F.Walk(Node).Cast<UEdGraphNode>();
 		if (!FoundNode) return;
 
+		F.PreEdit();
+
 		FoundNode->NodeComment = Comment;
 
 		// Make the comment bubble visible if setting a non-empty comment
@@ -45,8 +46,7 @@ public:
 			FoundNode->bCommentBubblePinned = true;
 		}
 
-		UBlueprint* BP = FBlueprintEditorUtils::FindBlueprintForNodeChecked(FoundNode);
-		FBlueprintEditorUtils::MarkBlueprintAsModified(BP);
+		F.PostEdit();
 
 		Result.Appendf(TEXT("Comment set on %s\n"), *MCPUtils::FormatName(FoundNode));
 	}

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

@@ -6,7 +6,6 @@
 #include "MCPUtils.h"
 #include "Engine/Blueprint.h"
 #include "EdGraph/EdGraphNode.h"
-#include "Kismet2/BlueprintEditorUtils.h"
 #include "GraphNode_SetPositions.generated.h"
 
 
@@ -53,6 +52,8 @@ public:
 		UBlueprint* BP = F.Walk(Blueprint).Cast<UBlueprint>();
 		if (!BP) return;
 
+		F.PreEdit();
+
 		int32 SuccessCount = 0;
 
 		for (const TSharedPtr<FJsonValue>& NodeVal : Nodes.Array)
@@ -70,7 +71,7 @@ public:
 			SuccessCount++;
 		}
 
-		FBlueprintEditorUtils::MarkBlueprintAsModified(BP);
+		F.PostEdit();
 		Result.Appendf(TEXT("Moved %d/%d nodes.\n"), SuccessCount, Nodes.Array.Num());
 	}
 };

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

@@ -5,7 +5,6 @@
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
 #include "EdGraph/EdGraphPin.h"
-#include "Kismet2/BlueprintEditorUtils.h"
 #include "GraphPin_Connect.generated.h"
 
 
@@ -49,6 +48,8 @@ public:
 		UBlueprint* BP = F.Walk(Blueprint).Cast<UBlueprint>();
 		if (!BP) return;
 
+		F.PreEdit();
+
 		int32 SuccessCount = 0;
 		int32 TotalCount = Connections.Array.Num();
 
@@ -81,10 +82,7 @@ public:
 			SuccessCount++;
 		}
 
-		if (SuccessCount > 0)
-		{
-			FBlueprintEditorUtils::MarkBlueprintAsModified(BP);
-		}
+		F.PostEdit();
 
 		Result.Appendf(TEXT("Connected %d/%d pins.\n"), SuccessCount, TotalCount);
 	}

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

@@ -5,7 +5,6 @@
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
 #include "EdGraph/EdGraphPin.h"
-#include "Kismet2/BlueprintEditorUtils.h"
 #include "GraphPin_Disconnect.generated.h"
 
 
@@ -50,6 +49,8 @@ public:
 		UBlueprint* BP = F.Walk(Blueprint).Cast<UBlueprint>();
 		if (!BP) return;
 
+		F.PreEdit();
+
 		int32 SuccessCount = 0;
 		int32 TotalDisconnected = 0;
 
@@ -97,10 +98,7 @@ public:
 			TotalDisconnected += DisconnectedCount;
 		}
 
-		if (TotalDisconnected > 0)
-		{
-			FBlueprintEditorUtils::MarkBlueprintAsModified(BP);
-		}
+		F.PostEdit();
 
 		Result.Appendf(TEXT("Done: %d/%d succeeded, %d links broken.\n"),
 			SuccessCount, Disconnections.Array.Num(), TotalDisconnected);

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/GraphPin_SetDefault.h

@@ -5,7 +5,6 @@
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
 #include "EdGraph/EdGraphPin.h"
-#include "Kismet2/BlueprintEditorUtils.h"
 #include "GraphPin_SetDefault.generated.h"
 
 

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

@@ -91,9 +91,10 @@ public:
 		}
 
 		// Set parent.
-		MI->PreEditChange(nullptr);
+		TArray<UObject*> Chain = { MI };
+		MCPUtils::PreEdit(Chain);
 		MI->Parent = ParentMaterialObj;
-		MI->PostEditChange();
+		MCPUtils::PostEdit(Chain);
 
 		// Save.
 		bool bSaved = MCPUtils::SaveGenericPackage(MI);

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

@@ -34,9 +34,10 @@ public:
 		if (!Assets.Exact(Material).Errors(Result).ENone().ETwo().Load()) return;
 		UMaterial* MaterialObj = Assets.Object();
 
-		// Force recompile by triggering PreEditChange/PostEditChange
-		MaterialObj->PreEditChange(nullptr);
-		MaterialObj->PostEditChange();
+		// Force recompile by triggering PreEdit/PostEdit
+		TArray<UObject*> Chain = { MaterialObj };
+		MCPUtils::PreEdit(Chain);
+		MCPUtils::PostEdit(Chain);
 
 		// Check for compilation errors via FMaterialResource on current platform
 		TArray<FString> Errors;

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

@@ -84,7 +84,8 @@ public:
 		// Apply optional properties.
 		bool bHasTwoSided = Json->HasField(TEXT("twoSided"));
 
-		MaterialObj->PreEditChange(nullptr);
+		TArray<UObject*> Chain = { MaterialObj };
+		MCPUtils::PreEdit(Chain);
 
 		if (!Domain.IsEmpty())
 			MaterialObj->MaterialDomain = ParsedDomain;
@@ -95,7 +96,7 @@ public:
 		if (bHasTwoSided)
 			MaterialObj->TwoSided = TwoSided;
 
-		MaterialObj->PostEditChange();
+		MCPUtils::PostEdit(Chain);
 
 		bool bSaved = MCPUtils::SaveMaterialPackage(MaterialObj);
 

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Material_ReparentInstance.h

@@ -74,9 +74,9 @@ public:
 			return;
 		}
 
-		MI->PreEditChange(nullptr);
+		MCPUtils::PreEdit({MI});
 		MI->Parent = NewParentObj;
-		MI->PostEditChange();
+		MCPUtils::PostEdit({MI});
 		MCPUtils::SaveGenericPackage(MI);
 
 		Result.Appendf(TEXT("Reparented %s: %s -> %s\n"),

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Material_SetInstanceParameter.h

@@ -159,9 +159,8 @@ public:
 
 		if (!DryRun)
 		{
-			MI->PreEditChange(nullptr);
-			MI->PostEditChange();
-			MI->MarkPackageDirty();
+			MCPUtils::PreEdit({MI});
+			MCPUtils::PostEdit({MI});
 			MCPUtils::SaveGenericPackage(MI);
 		}
 

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Material_SetProperty.h

@@ -55,7 +55,7 @@ public:
 			bool bValue = Json->GetBoolField(TEXT("value"));
 			OldValue = Getter() ? TEXT("true") : TEXT("false");
 			NewValue = bValue ? TEXT("true") : TEXT("false");
-			if (!DryRun) { Mat->PreEditChange(nullptr); Setter(bValue); Mat->PostEditChange(); }
+			if (!DryRun) Setter(bValue);
 		};
 
 		if (Property == TEXT("domain"))
@@ -65,7 +65,7 @@ public:
 			EMaterialDomain NewDomain;
 			if (!MCPUtils::StringToEnum(ValueStr, NewDomain, Result, TEXT("MD_"))) return;
 			NewValue = MCPUtils::EnumToString(NewDomain, TEXT("MD_"));
-			if (!DryRun) { Mat->PreEditChange(nullptr); Mat->MaterialDomain = NewDomain; Mat->PostEditChange(); }
+			if (!DryRun) Mat->MaterialDomain = NewDomain;
 		}
 		else if (Property == TEXT("blendMode"))
 		{
@@ -74,7 +74,7 @@ public:
 			EBlendMode NewBlend;
 			if (!MCPUtils::StringToEnum(ValueStr, NewBlend, Result, TEXT("BLEND_"))) return;
 			NewValue = MCPUtils::EnumToString(NewBlend, TEXT("BLEND_"));
-			if (!DryRun) { Mat->PreEditChange(nullptr); Mat->BlendMode = NewBlend; Mat->PostEditChange(); }
+			if (!DryRun) Mat->BlendMode = NewBlend;
 		}
 		else if (Property == TEXT("shadingModel"))
 		{
@@ -83,14 +83,14 @@ public:
 			EMaterialShadingModel NewModel;
 			if (!MCPUtils::StringToEnum(ValueStr, NewModel, Result, TEXT("MSM_"))) return;
 			NewValue = MCPUtils::EnumToString(NewModel, TEXT("MSM_"));
-			if (!DryRun) { Mat->PreEditChange(nullptr); Mat->SetShadingModel(NewModel); Mat->PostEditChange(); }
+			if (!DryRun) Mat->SetShadingModel(NewModel);
 		}
 		else if (Property == TEXT("opacity") || Property == TEXT("opacityMaskClipValue"))
 		{
 			double OpacityValue = Json->GetNumberField(TEXT("value"));
 			OldValue = FString::Printf(TEXT("%g"), Mat->OpacityMaskClipValue);
 			NewValue = FString::Printf(TEXT("%g"), OpacityValue);
-			if (!DryRun) { Mat->PreEditChange(nullptr); Mat->OpacityMaskClipValue = (float)OpacityValue; Mat->PostEditChange(); }
+			if (!DryRun) Mat->OpacityMaskClipValue = (float)OpacityValue;
 		}
 		else if (Property == TEXT("twoSided"))
 		{
@@ -124,9 +124,12 @@ public:
 			return;
 		}
 
-		// Save if not dry run
+		// Notify and save if not dry run
 		if (!DryRun)
 		{
+			TArray<UObject*> Chain = { Mat };
+			MCPUtils::PreEdit(Chain);
+			MCPUtils::PostEdit(Chain);
 			if (!MCPUtils::SaveMaterialPackage(Mat))
 				Result.Append(TEXT("WARNING: Package save failed\n"));
 		}

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

@@ -74,9 +74,8 @@ public:
 			return;
 		}
 
-		// Update properties
+		// Count and apply property changes
 		int32 ChangedCount = 0;
-		TransNode->PreEditChange(nullptr);
 
 		if (Json->HasField(TEXT("crossfadeDuration")))
 		{
@@ -109,7 +108,10 @@ public:
 			Result.Append(TEXT("ERROR: No properties to update. Provide at least one of: crossfadeDuration, blendMode, priorityOrder, logicType, bBidirectional\n"));
 			return;
 		}
-		TransNode->PostEditChange();
+
+		TArray<UObject*> Chain = { TransNode };
+		MCPUtils::PreEdit(Chain);
+		MCPUtils::PostEdit(Chain);
 
 		// Compile and save
 		FKismetEditorUtilities::CompileBlueprint(AnimBP);

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

@@ -1132,7 +1132,7 @@ void MCPUtils::PostEdit(const TArray<UObject*>& Objects)
 		Obj->MarkPackageDirty();
 
 		if (UBlueprint* BP = Cast<UBlueprint>(Obj))
-			FBlueprintEditorUtils::MarkBlueprintAsModified(BP);
+			FBlueprintEditorUtils::MarkBlueprintAsStructurallyModified(BP);
 	}
 }