diff --git a/pyproject.toml b/pyproject.toml
index de01bc2..4508eed 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -44,7 +44,7 @@ dependencies = [
     "azure-identity==1.25.3",
     "chromadb==1.5.8",
     "click>=8.1",
-    "langchain==1.2.15",
+    "langchain==1.3.9",
     "langchain-anthropic==1.4.1",
     "langchain-chroma==1.1.0",
     "langchain-community==0.4.1",