diff --git a/libs/langchain/langchain/llms/modal.py b/libs/langchain/langchain/llms/modal.py
index 9f1f42269d7..c18b1599375 100644
--- a/libs/langchain/langchain/llms/modal.py
+++ b/libs/langchain/langchain/llms/modal.py
@@ -91,7 +91,7 @@ class Modal(LLM):
             if prompt in response.json()["prompt"]:
                 response_json = response.json()
         except KeyError:
-            raise ValueError("LangChain requires 'prompt' key in response.")
+            raise KeyError("LangChain requires 'prompt' key in response.")
         text = response_json["prompt"]
         if stop is not None:
             # I believe this is required since the stop tokens