diff --git a/none/__init__.py b/none/__init__.py
index 081cddd6..279743c4 100644
--- a/none/__init__.py
+++ b/none/__init__.py
@@ -71,6 +71,9 @@ def get_bot() -> NoneBot:
     """
     Get the NoneBot instance.
 
+    The result is ensured to be not None, otherwise an exception will
+    be raised.
+
     :raise ValueError: instance not initialized
     """
     if _bot is None: