diff --git a/src/sprite.rs b/src/sprite.rs
index c8bae13..18b3186 100644
--- a/src/sprite.rs
+++ b/src/sprite.rs
@@ -56,6 +56,7 @@ impl Sprite {
 
 #[derive(Debug)]
 pub struct SpriteMissingRoomPosition;
+// todo "malformed sprite ID" or something
 
 impl Sprite {
     #[inline]