diff --git a/hw6/.env.example b/hw6/.env.example
index da67259..3a23e47 100644
--- a/hw6/.env.example
+++ b/hw6/.env.example
@@ -1 +1,2 @@
-OPENAI_API_KEY=""
\ No newline at end of file
+OPENAI_API_KEY=""
+LANGCHAIN_API_KEY=""
\ No newline at end of file