diff --git a/MANIFEST.in b/MANIFEST.in
index e322490e..6d7b1cd3 100644
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -1,2 +1,3 @@
+include langchain/py.typed
 include langchain/VERSION
 include LICENSE
diff --git a/langchain/py.typed b/langchain/py.typed
new file mode 100644
index 00000000..e69de29b