diff --git a/api/core/rag/index_processor/index_processor_base.py b/api/core/rag/index_processor/index_processor_base.py
index 2bcd1c79bb..c099fd1d5c 100644
--- a/api/core/rag/index_processor/index_processor_base.py
+++ b/api/core/rag/index_processor/index_processor_base.py
@@ -30,6 +30,7 @@ class BaseIndexProcessor(ABC):
     def load(self, dataset: Dataset, documents: list[Document], with_keywords: bool = True, **kwargs):
         raise NotImplementedError
 
+    @abstractmethod
     def clean(self, dataset: Dataset, node_ids: Optional[list[str]], with_keywords: bool = True, **kwargs):
         raise NotImplementedError