diff --git a/contributing/samples/hello_world/agent.py b/contributing/samples/hello_world/agent.py
index dade8425..28d1847a 100755
--- a/contributing/samples/hello_world/agent.py
+++ b/contributing/samples/hello_world/agent.py
@@ -65,7 +65,7 @@ async def check_prime(nums: list[int]) -> str:
 
 
 root_agent = Agent(
-    model='gemini-2.0-flash',
+    model='gemini-2.5-flash',
     name='hello_world_agent',
     description=(
         'hello world agent that can roll a dice of 8 sides and check prime'
diff --git a/contributing/samples/session_state_agent/agent.py b/contributing/samples/session_state_agent/agent.py
index 6c06c917..478d5065 100644
--- a/contributing/samples/session_state_agent/agent.py
+++ b/contributing/samples/session_state_agent/agent.py
@@ -172,7 +172,7 @@ root_agent = Agent(
         'Log all users query with `log_query` tool. Must always remind user you'
         ' cannot answer second query because your setup.'
     ),
-    model='gemini-2.0-flash-001',
+    model='gemini-2.5-flash',
     before_agent_callback=before_agent_callback,
     before_model_callback=before_model_callback,
     after_model_callback=after_model_callback,