diff --git a/ydb/core/tx/columnshard/engines/storage/optimizer/lcbuckets/constructor/constructor.cpp b/ydb/core/tx/columnshard/engines/storage/optimizer/lcbuckets/constructor/constructor.cpp
index bf813d2cc686..bb81a47a5307 100644
--- a/ydb/core/tx/columnshard/engines/storage/optimizer/lcbuckets/constructor/constructor.cpp
+++ b/ydb/core/tx/columnshard/engines/storage/optimizer/lcbuckets/constructor/constructor.cpp
@@ -18,6 +18,14 @@ bool TOptimizerPlannerConstructor::DoApplyToCurrentObject(IOptimizerPlanner& cur
 bool TOptimizerPlannerConstructor::DoIsEqualTo(const IOptimizerPlannerConstructor& item) const {
     const auto* itemClass = dynamic_cast<const TOptimizerPlannerConstructor*>(&item);
     AFL_VERIFY(itemClass);
+    if (Levels.size() != itemClass->Levels.size()) {
+        return false;
+    }
+    for (ui32 i = 0; i < Levels.size(); ++i) {
+        if (!Levels[i]->IsEqualTo(*itemClass->Levels[i].GetObjectPtrVerified())) {
+            return false;
+        }
+    }
     return true;
 }
 
@@ -61,8 +69,8 @@ NKikimr::TConclusionStatus TOptimizerPlannerConstructor::DoDeserializeFromJson(c
         if (!level) {
             return TConclusionStatus::Fail("incorrect level class_name: " + className);
         }
-        if (!level->DeserializeFromJson(i["description"])) {
-            return TConclusionStatus::Fail("cannot parse level: " + className + ": " + i["description"].GetStringRobust());
+        if (!level->DeserializeFromJson(i)) {
+            return TConclusionStatus::Fail("cannot parse level: " + i.GetStringRobust());
         }
         Levels.emplace_back(TLevelConstructorContainer(std::shared_ptr<ILevelConstructor>(level.Release())));
     }
diff --git a/ydb/core/tx/columnshard/engines/storage/optimizer/lcbuckets/constructor/constructor.h b/ydb/core/tx/columnshard/engines/storage/optimizer/lcbuckets/constructor/constructor.h
index f85249435eac..78a73993c57f 100644
--- a/ydb/core/tx/columnshard/engines/storage/optimizer/lcbuckets/constructor/constructor.h
+++ b/ydb/core/tx/columnshard/engines/storage/optimizer/lcbuckets/constructor/constructor.h
@@ -12,6 +12,7 @@ class ILevelConstructor {
     virtual TConclusionStatus DoDeserializeFromJson(const NJson::TJsonValue& json) = 0;
     virtual bool DoDeserializeFromProto(const NKikimrSchemeOp::TCompactionLevelConstructorContainer& proto) = 0;
     virtual void DoSerializeToProto(NKikimrSchemeOp::TCompactionLevelConstructorContainer& proto) const = 0;
+    virtual bool IsEqualToSameClass(const ILevelConstructor& item) const = 0;
 
 public:
     using TFactory = NObjectFactory::TObjectFactory<ILevelConstructor, TString>;
@@ -19,6 +20,13 @@ class ILevelConstructor {
 
     virtual ~ILevelConstructor() = default;
 
+    bool IsEqualTo(const ILevelConstructor& item) const {
+        if (GetClassName() != item.GetClassName()) {
+            return false;
+        }
+        return IsEqualToSameClass(item);
+    }
+
     std::shared_ptr<IPortionsLevel> BuildLevel(
         const std::shared_ptr<IPortionsLevel>& nextLevel, const ui32 indexLevel, const TLevelCounters& counters) const {
         return DoBuildLevel(nextLevel, indexLevel, counters);
diff --git a/ydb/core/tx/columnshard/engines/storage/optimizer/lcbuckets/constructor/zero_level.cpp b/ydb/core/tx/columnshard/engines/storage/optimizer/lcbuckets/constructor/zero_level.cpp
index 6a02746bc447..7b5d8599ec1c 100644
--- a/ydb/core/tx/columnshard/engines/storage/optimizer/lcbuckets/constructor/zero_level.cpp
+++ b/ydb/core/tx/columnshard/engines/storage/optimizer/lcbuckets/constructor/zero_level.cpp
@@ -5,6 +5,9 @@
 namespace NKikimr::NOlap::NStorageOptimizer::NLCBuckets {
 
 TConclusionStatus TZeroLevelConstructor::DoDeserializeFromJson(const NJson::TJsonValue& json) {
+    if (!json.IsMap()) {
+        return TConclusionStatus::Fail("incorrect level description");
+    }
     if (json.Has("portions_live_duration")) {
         const auto& jsonValue = json["portions_live_duration"];
         if (!jsonValue.IsString()) {
diff --git a/ydb/core/tx/columnshard/engines/storage/optimizer/lcbuckets/constructor/zero_level.h b/ydb/core/tx/columnshard/engines/storage/optimizer/lcbuckets/constructor/zero_level.h
index 531c60f3690d..b80dc88d2a62 100644
--- a/ydb/core/tx/columnshard/engines/storage/optimizer/lcbuckets/constructor/zero_level.h
+++ b/ydb/core/tx/columnshard/engines/storage/optimizer/lcbuckets/constructor/zero_level.h
@@ -18,6 +18,10 @@ class TZeroLevelConstructor: public ILevelConstructor {
     virtual TConclusionStatus DoDeserializeFromJson(const NJson::TJsonValue& json) override;
     virtual bool DoDeserializeFromProto(const NKikimrSchemeOp::TCompactionLevelConstructorContainer& proto) override;
     virtual void DoSerializeToProto(NKikimrSchemeOp::TCompactionLevelConstructorContainer& proto) const override;
+    virtual bool IsEqualToSameClass(const ILevelConstructor& item) const override {
+        const auto& itemCast = dynamic_cast<const TZeroLevelConstructor&>(item);
+        return PortionsLiveDuration == itemCast.PortionsLiveDuration && ExpectedBlobsSize == itemCast.ExpectedBlobsSize;
+    }
 
     static const inline TFactory::TRegistrator<TZeroLevelConstructor> Registrator = TFactory::TRegistrator<TZeroLevelConstructor>(GetClassNameStatic());