diff --git a/API.md b/API.md
index 8430366..3840494 100644
--- a/API.md
+++ b/API.md
@@ -50,7 +50,8 @@ i3.new_tab("stuff", {
 			-- Do things
 		end
 
-		-- No need to update the formspec, it's automatic
+		-- To prevent a formspec update, return false.
+		-- Otherwise, it's automatic.
 	end,
 })
 ```