From 62a30efb1272eee46289e587f27123112cb5d2c7 Mon Sep 17 00:00:00 2001
From: Nuno Campos <nuno@langchain.dev>
Date: Mon, 26 Feb 2024 10:27:07 -0800
Subject: [PATCH] Fix bug with using configurable_fields after
 configurable_alternatives (#18139)

Closes #17915
---
 libs/core/langchain_core/runnables/configurable.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/libs/core/langchain_core/runnables/configurable.py b/libs/core/langchain_core/runnables/configurable.py
index ea4ed30e66c..8339b1d12d8 100644
--- a/libs/core/langchain_core/runnables/configurable.py
+++ b/libs/core/langchain_core/runnables/configurable.py
@@ -441,6 +441,8 @@ class RunnableConfigurableAlternatives(DynamicRunnable[Input, Output]):
             which=self.which,
             default=self.default.configurable_fields(**kwargs),
             alternatives=self.alternatives,
+            default_key=self.default_key,
+            prefix_keys=self.prefix_keys,
         )
 
     def _prepare(