diff --git a/libs/langchain/langchain/schema/runnable/base.py b/libs/langchain/langchain/schema/runnable/base.py
index 5fec1c86c..fcba9c4c1 100644
--- a/libs/langchain/langchain/schema/runnable/base.py
+++ b/libs/langchain/langchain/schema/runnable/base.py
@@ -235,7 +235,7 @@ class Runnable(Generic[Input, Output], ABC):
             )
 
         return (
-            config
+            list(map(ensure_config, config))
             if isinstance(config, list)
             else [deepcopy(ensure_config(config)) for _ in range(length)]
         )