diff --git a/src/google/adk/cli/utils/agent_loader.py b/src/google/adk/cli/utils/agent_loader.py
index 5b892487..0bc44abd 100644
--- a/src/google/adk/cli/utils/agent_loader.py
+++ b/src/google/adk/cli/utils/agent_loader.py
@@ -178,7 +178,9 @@ class AgentLoader(BaseAgentLoader):
     if root_agent := self._load_from_submodule(agent_name):
       return root_agent
 
-    if root_agent := self._load_from_yaml_config(agent_name):
+    if os.getenv("ADK_ALLOW_WIP_FEATURES") and (
+        root_agent := self._load_from_yaml_config(agent_name)
+    ):
       return root_agent
 
     # If no root_agent was found by any pattern