diff --git a/card_game/src/lib.rs b/card_game/src/lib.rs
index 5732300..601db9f 100644
--- a/card_game/src/lib.rs
+++ b/card_game/src/lib.rs
@@ -35,6 +35,7 @@ pub trait Game: Clone {
 }
 
 /// Call .commit() to run the staged instruction.
+/// Cannot be constructed other than by Game::stage_instruction.
 pub struct StagedInstruction<'a, G: Game> {
 	game: &'a mut G,
 	stats: &'a mut G::Stats,