diff --git a/AyCode.Core.Serializers.SourceGenerator/AcBinarySourceGenerator.cs b/AyCode.Core.Serializers.SourceGenerator/AcBinarySourceGenerator.cs
index dcae6fe..f0402ae 100644
--- a/AyCode.Core.Serializers.SourceGenerator/AcBinarySourceGenerator.cs
+++ b/AyCode.Core.Serializers.SourceGenerator/AcBinarySourceGenerator.cs
@@ -248,9 +248,18 @@ public class AcBinarySourceGenerator : IIncrementalGenerator
         // Markerless types: write raw value only, no type marker, no PropertySkip
         // Matches runtime WritePropertyMarkerless — these have ExpectedTypeCode
         // NEVER filtered (runtime doesn't filter markerless properties either)
+        // UseMetadata=true: markerless path NOT available — must use markered path (EmitSkip)
+        // to match runtime WritePropertyOrSkip behavior (every property gets a type marker byte)
         if (IsMarkerless(p.TypeKind))
         {
-            EmitMarkerless(sb, p.TypeKind, a, i);
+            sb.AppendLine($"{i}if (context.UseMetadata)");
+            sb.AppendLine($"{i}{{");
+            EmitSkip(sb, p.TypeKind, a, p.TypeNameForTypeof, i + "    ");
+            sb.AppendLine($"{i}}}");
+            sb.AppendLine($"{i}else");
+            sb.AppendLine($"{i}{{");
+            EmitMarkerless(sb, p.TypeKind, a, i + "    ");
+            sb.AppendLine($"{i}}}");
             return;
         }
 
@@ -366,8 +375,9 @@ public class AcBinarySourceGenerator : IIncrementalGenerator
     /// <summary>
     /// Emits direct object write — bypasses GetWrapper + WriteObject entirely.
     /// Writes marker bytes + calls child GeneratedWriter.WriteProperties inline.
-    /// For IId types: inlines TryConsumeWritePlanEntry for ref tracking cursor alignment.
-    /// Falls back to WriteObjectGenerated when context.IsDirectObjectWrite is false (UseMetadata/PropertyFilter).
+    /// IId types: guard ReferenceHandling != None (tracked in OnlyId + All).
+    /// Non-IId types: guard ReferenceHandling == All (tracked only in All mode).
+    /// Falls back to WriteObjectGenerated when context.IsDirectObjectWrite is false (UseMetadata).
     /// </summary>
     private static void EmitDirectObjectWrite(StringBuilder sb, PropInfo p, string a, string i)
     {
@@ -391,50 +401,32 @@ public class AcBinarySourceGenerator : IIncrementalGenerator
         sb.AppendLine($"{i}    else");
         sb.AppendLine($"{i}    {{");
 
-        if (p.IsIId)
-        {
-            // IId type: inline ref tracking from WriteObject
-            // context.UseTypeReferenceHandling gate: ReferenceHandling != None && IsIId
-            // For IId types, IsIId is always true, so: ReferenceHandling != None
-            sb.AppendLine($"{i}        if (context.ReferenceHandling != ReferenceHandlingMode.None && context.TryConsumeWritePlanEntry(out var pe_{p.Name}))");
-            sb.AppendLine($"{i}        {{");
-            sb.AppendLine($"{i}            if (!pe_{p.Name}.IsFirst)");
-            sb.AppendLine($"{i}            {{");
-            // 2+ occurrence → ObjectRef + cacheIndex (no properties written)
-            sb.AppendLine($"{i}                context.WriteByte(BinaryTypeCode.ObjectRef);");
-            sb.AppendLine($"{i}                context.WriteVarUInt((uint)pe_{p.Name}.CacheMapIndex);");
-            sb.AppendLine($"{i}            }}");
-            sb.AppendLine($"{i}            else");
-            sb.AppendLine($"{i}            {{");
-            // First occurrence → ObjectRefFirst + cacheIndex + properties
-            sb.AppendLine($"{i}                context.WriteByte(BinaryTypeCode.ObjectRefFirst);");
-            sb.AppendLine($"{i}                context.WriteVarUInt((uint)pe_{p.Name}.CacheMapIndex);");
-            sb.AppendLine($"{i}                {writer}.Instance.WriteProperties({a}, context, {nextDepth});");
-            sb.AppendLine($"{i}            }}");
-            sb.AppendLine($"{i}        }}");
-            sb.AppendLine($"{i}        else");
-            sb.AppendLine($"{i}        {{");
-            // No ref tracking entry at this visit → plain Object marker
-            sb.AppendLine($"{i}            context.WriteByte(BinaryTypeCode.Object);");
-            sb.AppendLine($"{i}            {writer}.Instance.WriteProperties({a}, context, {nextDepth});");
-            sb.AppendLine($"{i}        }}");
-        }
-        else
-        {
-            // Non-IId type: usually no ref tracking needed.
-            // Exception: ReferenceHandling == All tracks ALL objects → scan pass increments ScanVisitIndex,
-            // so write pass must also consume from WritePlan to keep cursor aligned.
-            // Guard: fall back to WriteObjectGenerated for All mode (rare). OnlyId mode is safe (non-IId skipped).
-            sb.AppendLine($"{i}        if (context.ReferenceHandling == ReferenceHandlingMode.All)");
-            sb.AppendLine($"{i}        {{");
-            sb.AppendLine($"{i}            AcBinarySerializer.WriteObjectGenerated({a}, typeof({p.TypeNameForTypeof}), context, depth);");
-            sb.AppendLine($"{i}        }}");
-            sb.AppendLine($"{i}        else");
-            sb.AppendLine($"{i}        {{");
-            sb.AppendLine($"{i}            context.WriteByte(BinaryTypeCode.Object);");
-            sb.AppendLine($"{i}            {writer}.Instance.WriteProperties({a}, context, {nextDepth});");
-            sb.AppendLine($"{i}        }}");
-        }
+        // Inline ref tracking: guard depends on IId vs non-IId to match scan pass behavior.
+        // IId types: tracked in OnlyId + All → guard: ReferenceHandling != None
+        // Non-IId types: tracked only in All → guard: ReferenceHandling == All
+        // This matches UseTypeReferenceHandling: (IsIId || ReferenceHandling == All) && ReferenceHandling != None
+        var refGuard = p.IsIId
+            ? "context.ReferenceHandling != ReferenceHandlingMode.None"
+            : "context.ReferenceHandling == ReferenceHandlingMode.All";
+        sb.AppendLine($"{i}        if ({refGuard} && context.TryConsumeWritePlanEntry(out var pe_{p.Name}))");
+        sb.AppendLine($"{i}        {{");
+        sb.AppendLine($"{i}            if (!pe_{p.Name}.IsFirst)");
+        sb.AppendLine($"{i}            {{");
+        sb.AppendLine($"{i}                context.WriteByte(BinaryTypeCode.ObjectRef);");
+        sb.AppendLine($"{i}                context.WriteVarUInt((uint)pe_{p.Name}.CacheMapIndex);");
+        sb.AppendLine($"{i}            }}");
+        sb.AppendLine($"{i}            else");
+        sb.AppendLine($"{i}            {{");
+        sb.AppendLine($"{i}                context.WriteByte(BinaryTypeCode.ObjectRefFirst);");
+        sb.AppendLine($"{i}                context.WriteVarUInt((uint)pe_{p.Name}.CacheMapIndex);");
+        sb.AppendLine($"{i}                {writer}.Instance.WriteProperties({a}, context, {nextDepth});");
+        sb.AppendLine($"{i}            }}");
+        sb.AppendLine($"{i}        }}");
+        sb.AppendLine($"{i}        else");
+        sb.AppendLine($"{i}        {{");
+        sb.AppendLine($"{i}            context.WriteByte(BinaryTypeCode.Object);");
+        sb.AppendLine($"{i}            {writer}.Instance.WriteProperties({a}, context, {nextDepth});");
+        sb.AppendLine($"{i}        }}");
 
         sb.AppendLine($"{i}    }}");
         sb.AppendLine($"{i}}}");
@@ -508,41 +500,31 @@ public class AcBinarySourceGenerator : IIncrementalGenerator
         sb.AppendLine($"{i}        if ({e} == null) {{ context.WriteByte(BinaryTypeCode.Null); continue; }}");
         sb.AppendLine($"{i}        if (nextDepth_{p.Name} > context.MaxDepth) {{ context.WriteByte(BinaryTypeCode.Null); continue; }}");
 
-        if (p.ElementIsIId)
-        {
-            sb.AppendLine($"{i}        if (context.ReferenceHandling != ReferenceHandlingMode.None && context.TryConsumeWritePlanEntry(out var epe_{p.Name}))");
-            sb.AppendLine($"{i}        {{");
-            sb.AppendLine($"{i}            if (!epe_{p.Name}.IsFirst)");
-            sb.AppendLine($"{i}            {{");
-            sb.AppendLine($"{i}                context.WriteByte(BinaryTypeCode.ObjectRef);");
-            sb.AppendLine($"{i}                context.WriteVarUInt((uint)epe_{p.Name}.CacheMapIndex);");
-            sb.AppendLine($"{i}            }}");
-            sb.AppendLine($"{i}            else");
-            sb.AppendLine($"{i}            {{");
-            sb.AppendLine($"{i}                context.WriteByte(BinaryTypeCode.ObjectRefFirst);");
-            sb.AppendLine($"{i}                context.WriteVarUInt((uint)epe_{p.Name}.CacheMapIndex);");
-            sb.AppendLine($"{i}                {writer}.Instance.WriteProperties({e}, context, nextDepth_{p.Name});");
-            sb.AppendLine($"{i}            }}");
-            sb.AppendLine($"{i}        }}");
-            sb.AppendLine($"{i}        else");
-            sb.AppendLine($"{i}        {{");
-            sb.AppendLine($"{i}            context.WriteByte(BinaryTypeCode.Object);");
-            sb.AppendLine($"{i}            {writer}.Instance.WriteProperties({e}, context, nextDepth_{p.Name});");
-            sb.AppendLine($"{i}        }}");
-        }
-        else
-        {
-            // Non-IId element: guard against ReferenceHandling.All (cursor alignment)
-            sb.AppendLine($"{i}        if (context.ReferenceHandling == ReferenceHandlingMode.All)");
-            sb.AppendLine($"{i}        {{");
-            sb.AppendLine($"{i}            AcBinarySerializer.WriteObjectGenerated({e}, typeof({elemType}), context, nextDepth_{p.Name} - 1);");
-            sb.AppendLine($"{i}        }}");
-            sb.AppendLine($"{i}        else");
-            sb.AppendLine($"{i}        {{");
-            sb.AppendLine($"{i}            context.WriteByte(BinaryTypeCode.Object);");
-            sb.AppendLine($"{i}            {writer}.Instance.WriteProperties({e}, context, nextDepth_{p.Name});");
-            sb.AppendLine($"{i}        }}");
-        }
+        // Inline ref tracking: guard depends on IId vs non-IId element type to match scan pass.
+        // IId elements: tracked in OnlyId + All → guard: ReferenceHandling != None
+        // Non-IId elements: tracked only in All → guard: ReferenceHandling == All
+        var elemRefGuard = p.ElementIsIId
+            ? "context.ReferenceHandling != ReferenceHandlingMode.None"
+            : "context.ReferenceHandling == ReferenceHandlingMode.All";
+        sb.AppendLine($"{i}        if ({elemRefGuard} && context.TryConsumeWritePlanEntry(out var epe_{p.Name}))");
+        sb.AppendLine($"{i}        {{");
+        sb.AppendLine($"{i}            if (!epe_{p.Name}.IsFirst)");
+        sb.AppendLine($"{i}            {{");
+        sb.AppendLine($"{i}                context.WriteByte(BinaryTypeCode.ObjectRef);");
+        sb.AppendLine($"{i}                context.WriteVarUInt((uint)epe_{p.Name}.CacheMapIndex);");
+        sb.AppendLine($"{i}            }}");
+        sb.AppendLine($"{i}            else");
+        sb.AppendLine($"{i}            {{");
+        sb.AppendLine($"{i}                context.WriteByte(BinaryTypeCode.ObjectRefFirst);");
+        sb.AppendLine($"{i}                context.WriteVarUInt((uint)epe_{p.Name}.CacheMapIndex);");
+        sb.AppendLine($"{i}                {writer}.Instance.WriteProperties({e}, context, nextDepth_{p.Name});");
+        sb.AppendLine($"{i}            }}");
+        sb.AppendLine($"{i}        }}");
+        sb.AppendLine($"{i}        else");
+        sb.AppendLine($"{i}        {{");
+        sb.AppendLine($"{i}            context.WriteByte(BinaryTypeCode.Object);");
+        sb.AppendLine($"{i}            {writer}.Instance.WriteProperties({e}, context, nextDepth_{p.Name});");
+        sb.AppendLine($"{i}        }}");
 
         sb.AppendLine($"{i}    }}");
         sb.AppendLine($"{i}}}");
diff --git a/AyCode.Core/Serializers/Binaries/AcBinarySerializer.cs b/AyCode.Core/Serializers/Binaries/AcBinarySerializer.cs
index 223ea11..d9d1755 100644
--- a/AyCode.Core/Serializers/Binaries/AcBinarySerializer.cs
+++ b/AyCode.Core/Serializers/Binaries/AcBinarySerializer.cs
@@ -1089,7 +1089,7 @@ public static partial class AcBinarySerializer
         if (context.UseGeneratedCode)
         {
             var generatedWriter = wrapper.GeneratedWriter;
-            if (generatedWriter != null && !context.UseMetadata)
+            if (generatedWriter != null)
             {
                 generatedWriter.WriteProperties(value, context, nextDepth);
                 return;
diff --git a/AyCode.Core/Serializers/Binaries/AcBinarySerializerOptions.cs b/AyCode.Core/Serializers/Binaries/AcBinarySerializerOptions.cs
index 6b01f75..e0fff73 100644
--- a/AyCode.Core/Serializers/Binaries/AcBinarySerializerOptions.cs
+++ b/AyCode.Core/Serializers/Binaries/AcBinarySerializerOptions.cs
@@ -82,7 +82,7 @@ public sealed class AcBinarySerializerOptions : AcSerializerOptions
     /// allowing the deserializer to match properties by name between different types.
     /// Default: false (no overhead)
     /// </summary>
-    public bool UseMetadata { get; set; } = false;
+    public bool UseMetadata { get; set; } = true;
 
     public bool UseGeneratedCode { get; set; } = true;