docs: Update gemini model in docstrings for RAG Engine

agentplatform/rag/rag_data.py

@@ -1021,7 +1021,7 @@ def add_inline_citations_and_references(
       )
 
     rag_model = GenerativeModel(
-        model_name="gemini-2.5-pro-preview-05-06", tools=[rag_retrieval_tool]
+        model_name="gemini-3.8-flash", tools=[rag_retrieval_tool]
     )
     response = rag_model.generate_content("Why is the sky blue?")
 

agentplatform/rag/rag_retrieval.py

@@ -46,8 +46,8 @@ def retrieval_query(
             vector_distance_threshold=0.5
         ),
         ranking=agentplatform.rag.Ranking(
-            llm_ranker=rag.LlmRanker(
-                model_name="gemini-2.5-flash"
+            llm_ranker=agentplatform.rag.LlmRanker(
+                model_name="gemini-3.8-flash"
             )
         )
     )

agentplatform/rag/rag_store.py

@@ -61,7 +61,7 @@ def __init__(
             ),
             ranking=vertex.rag.Ranking(
                 llm_ranker=agentplatform.rag.LlmRanker(
-                    model_name="gemini-1.5-flash-002"
+                    model_name="gemini-3.8-flash"
                 )
             )
         )

vertexai/rag/rag_data.py

@@ -1045,7 +1045,7 @@ def add_inline_citations_and_references(
       )
 
     rag_model = GenerativeModel(
-        model_name="gemini-2.5-pro-preview-05-06", tools=[rag_retrieval_tool]
+        model_name="gemini-3.8-flash", tools=[rag_retrieval_tool]
     )
     response = rag_model.generate_content("Why is the sky blue?")
 

vertexai/rag/rag_retrieval.py

@@ -49,7 +49,7 @@ def retrieval_query(
         ),
         ranking=vertex.rag.Ranking(
             llm_ranker=vertexai.rag.LlmRanker(
-                model_name="gemini-1.5-flash-002"
+                model_name="gemini-3.8-flash"
             )
         )
     )

vertexai/rag/rag_store.py

@@ -64,7 +64,7 @@ def __init__(
             ),
             ranking=vertex.rag.Ranking(
                 llm_ranker=vertexai.rag.LlmRanker(
-                    model_name="gemini-1.5-flash-002"
+                    model_name="gemini-3.8-flash"
                 )
             )
         )