diff --git a/server/reflector/utils/common.py b/server/reflector/utils/common.py
new file mode 100644
index 00000000..f5fa4cbf
--- /dev/null
+++ b/server/reflector/utils/common.py
@@ -0,0 +1,4 @@
+def assert_not_none[T](value: T | None, message: str = "Value is None") -> T:
+    if value is None:
+        raise ValueError(message)
+    return value