diff --git a/packages/openpi-client/pyproject.toml b/packages/openpi-client/pyproject.toml
index 160db378bd..336d98112d 100644
--- a/packages/openpi-client/pyproject.toml
+++ b/packages/openpi-client/pyproject.toml
@@ -7,6 +7,7 @@ dependencies = [
     "msgpack>=1.0.5",
     "numpy>=1.22.4,<2.0.0",
     "pillow>=9.0.0",
+    "typing-extensions>=4.12.2",
     "websockets>=11.0",
 ]