Lots of crap

Plugins/BlueprintMCP/Source/BlueprintMCP/Private/LogCapture.h

@@ -0,0 +1,34 @@
+#pragma once
+
+#include "CoreMinimal.h"
+
+class FLogCaptureOutputDevice : public FOutputDevice
+{
+public:
+	TArray<FString> CapturedErrors;
+	bool bEnabled = true;
+
+	void Install() { GLog->AddOutputDevice(this); }
+	void Uninstall() { GLog->RemoveOutputDevice(this); }
+
+	// If the device is marked 'CanBeUsedOnMultipleThreads,'
+	// then UE_LOG will call Serialize from the current
+	// thread, otherwise, it will call Serialize from the
+	// logging thread.  Without this, we wouldn't be able to
+	// tell whether an error is coming from the game thread.
+	virtual bool CanBeUsedOnMultipleThreads() const override { return true; }
+
+	virtual void Serialize(const TCHAR* V, ELogVerbosity::Type Verbosity, const FName& Category) override
+	{
+		// Only capture messages from the game thread.
+		// Other threads generate noise we don't care about.
+		if (!IsInGameThread() || !bEnabled) return;
+
+		if (Verbosity == ELogVerbosity::Warning ||
+			Verbosity == ELogVerbosity::Error ||
+			Verbosity == ELogVerbosity::Fatal)
+		{
+			CapturedErrors.Add(FString(V));
+		}
+	}
+};

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

@@ -0,0 +1,24 @@
+#include "MCPProperty.h"
+#include "MCPUtils.h"
+
+MCPProperty::MCPProperty(FProperty* InProp, void* Container)
+	: Prop(InProp), ValuePtr(InProp ? InProp->ContainerPtrToValuePtr<void>(Container) : nullptr) {}
+
+FString MCPProperty::GetText() const
+{
+	FString Result;
+	Prop->ExportTextItem_Direct(Result, ValuePtr, nullptr, nullptr, PPF_None);
+	return Result;
+}
+
+bool MCPProperty::SetText(const FString& Value, MCPErrorCallback Error)
+{
+	const TCHAR* ImportResult = Prop->ImportText_Direct(*Value, ValuePtr, nullptr, PPF_None);
+	if (!ImportResult)
+	{
+		Error.SetError(FString::Printf(TEXT("Failed to parse '%s' for property '%s' (type: %s)"),
+			*Value, *MCPUtils::FormatName(Prop), *Prop->GetCPPType()));
+		return false;
+	}
+	return true;
+}

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

@@ -1,5 +1,6 @@
 #include "MCPServer.h"
 #include "MCPHandler.h"
+#include "LogCapture.h"
 #include "MCPUtils.h"
 #include "MCPAssetFinder.h"
 #include "UObject/StrongObjectPtr.h"
@@ -151,6 +152,8 @@ void UMCPServer::Initialize(FSubsystemCollectionBase& Collection)
 	}
 
 	BuildMCPHandlerRegistry();
+	LogCapture.bEnabled = false;
+	LogCapture.Install();
 	bRunning = true;
 	UE_LOG(LogTemp, Display, TEXT("BlueprintMCP: MCP server listening on tcp://localhost:%d"), Port);
 }
@@ -204,6 +207,7 @@ void UMCPServer::Deinitialize()
 		ListenSocket = nullptr;
 	}
 
+	LogCapture.Uninstall();
 	bRunning = false;
 	bShuttingDown = false;
 	UE_LOG(LogTemp, Display, TEXT("BlueprintMCP: Server stopped."));
@@ -294,9 +298,19 @@ FString UMCPServer::HandleRequest(const FString& Line)
 		return PopulateError.ToString();
 	}
 
-	// Invoke the handler.
+	// Invoke the handler with log capture.
+	LogCapture.CapturedErrors.Empty();
+	LogCapture.bEnabled = true;
 	TStringBuilder<32768> TextResult;
 	Handler->Handle(TextResult);
+	LogCapture.bEnabled = false;
+	for (const FString& Msg : LogCapture.CapturedErrors)
+	{
+		TextResult.Append(TEXT("LOG: "));
+		TextResult.Append(Msg);
+		TextResult.Append(TEXT("\n"));
+	}
+	LogCapture.CapturedErrors.Empty();
 	FString Result = TextResult.ToString();
 	for (int32 i = 0; i < Result.Len(); ++i)
 	{