diff --git a/metagpt/rag/factories/index.py b/metagpt/rag/factories/index.py
index cdac64fa6..6aad695e7 100644
--- a/metagpt/rag/factories/index.py
+++ b/metagpt/rag/factories/index.py
@@ -29,9 +29,6 @@ class RAGIndexFactory(ConfigBasedFactory):
         """Key is PersistType."""
         return super().get_instance(config, **kwargs)
 
-    def _extract_embed_model(self, config, **kwargs) -> BaseEmbedding:
-        return self._val_from_config_or_kwargs("embed_model", config, **kwargs)
-
     def _create_faiss(self, config: FAISSIndexConfig, **kwargs) -> VectorStoreIndex:
         embed_model = self._extract_embed_model(config, **kwargs)
 
@@ -59,5 +56,8 @@ class RAGIndexFactory(ConfigBasedFactory):
         index = load_index_from_storage(storage_context=storage_context, embed_model=embed_model)
         return index
 
+    def _extract_embed_model(self, config, **kwargs) -> BaseEmbedding:
+        return self._val_from_config_or_kwargs("embed_model", config, **kwargs)
+
 
 get_index = RAGIndexFactory().get_index
diff --git a/metagpt/rag/factories/ranker.py b/metagpt/rag/factories/ranker.py
index 753041c6b..f05599e15 100644
--- a/metagpt/rag/factories/ranker.py
+++ b/metagpt/rag/factories/ranker.py
@@ -24,12 +24,12 @@ class RankerFactory(ConfigBasedFactory):
 
         return super().get_instances(configs, **kwargs)
 
-    def _extract_llm(self, config: BaseRankerConfig = None, **kwargs) -> LLM:
-        return self._val_from_config_or_kwargs("llm", config, **kwargs)
-
     def _create_llm_ranker(self, config: LLMRankerConfig, **kwargs) -> LLMRerank:
         config.llm = self._extract_llm(config, **kwargs)
         return LLMRerank(**config.model_dump())
 
+    def _extract_llm(self, config: BaseRankerConfig = None, **kwargs) -> LLM:
+        return self._val_from_config_or_kwargs("llm", config, **kwargs)
+
 
 get_rankers = RankerFactory().get_rankers
diff --git a/metagpt/rag/factories/retriever.py b/metagpt/rag/factories/retriever.py
index e5e810b45..ba48c753e 100644
--- a/metagpt/rag/factories/retriever.py
+++ b/metagpt/rag/factories/retriever.py
@@ -50,21 +50,6 @@ class RetrieverFactory(ConfigBasedFactory):
     def _create_default(self, **kwargs) -> RAGRetriever:
         return self._extract_index(**kwargs).as_retriever()
 
-    def _extract_index(self, config: BaseRetrieverConfig = None, **kwargs) -> VectorStoreIndex:
-        return self._val_from_config_or_kwargs("index", config, **kwargs)
-
-    def _build_index_from_vector_store(
-        self, config: IndexRetrieverConfig, vector_store: BasePydanticVectorStore, **kwargs
-    ) -> VectorStoreIndex:
-        storage_context = StorageContext.from_defaults(vector_store=vector_store)
-        old_index = self._extract_index(config, **kwargs)
-        new_index = VectorStoreIndex(
-            nodes=list(old_index.docstore.docs.values()),
-            storage_context=storage_context,
-            embed_model=old_index._embed_model,
-        )
-        return new_index
-
     def _create_faiss_retriever(self, config: FAISSRetrieverConfig, **kwargs) -> FAISSRetriever:
         vector_store = FaissVectorStore(faiss_index=faiss.IndexFlatL2(config.dimensions))
         config.index = self._build_index_from_vector_store(config, vector_store, **kwargs)
@@ -82,5 +67,20 @@ class RetrieverFactory(ConfigBasedFactory):
         config.index = self._build_index_from_vector_store(config, vector_store, **kwargs)
         return ChromaRetriever(**config.model_dump())
 
+    def _extract_index(self, config: BaseRetrieverConfig = None, **kwargs) -> VectorStoreIndex:
+        return self._val_from_config_or_kwargs("index", config, **kwargs)
+
+    def _build_index_from_vector_store(
+        self, config: IndexRetrieverConfig, vector_store: BasePydanticVectorStore, **kwargs
+    ) -> VectorStoreIndex:
+        storage_context = StorageContext.from_defaults(vector_store=vector_store)
+        old_index = self._extract_index(config, **kwargs)
+        new_index = VectorStoreIndex(
+            nodes=list(old_index.docstore.docs.values()),
+            storage_context=storage_context,
+            embed_model=old_index._embed_model,
+        )
+        return new_index
+
 
 get_retriever = RetrieverFactory().get_retriever