diff --git a/ui/IconButton.gd b/ui/IconButton.gd
index 7b9fdad..75ca542 100644
--- a/ui/IconButton.gd
+++ b/ui/IconButton.gd
@@ -1,3 +1,4 @@
+@tool
 class_name IconButton
 extends Control
 
@@ -142,6 +143,11 @@ func _blocked_by_modal() -> bool:
 
 
 func _gui_input(event: InputEvent) -> void:
+	# @tool runs this in the editor too, where a click on the canvas would
+	# emit `pressed` at whatever it is wired to. The glyph is what we want
+	# visible there, not the behaviour.
+	if Engine.is_editor_hint():
+		return
 	if _blocked_by_modal():
 		return
 	if event is InputEventScreenTouch:
diff --git a/ui/NeonPanel.gd b/ui/NeonPanel.gd
index 55803ab..1fb1e36 100644
--- a/ui/NeonPanel.gd
+++ b/ui/NeonPanel.gd
@@ -1,3 +1,4 @@
+@tool
 class_name NeonPanel
 extends Control
 
@@ -39,6 +40,12 @@ var design_centre: Vector2 = Vector2.ZERO
 
 
 func _ready() -> void:
+	# _fit_to_screen() below rewrites offset_left/right/top/bottom. Under
+	# @tool that runs against the editor viewport, overwriting the authored
+	# layout and dirtying the scene, so the card previews at its authored
+	# size and is only ever fitted at runtime.
+	if Engine.is_editor_hint():
+		return
 	# Fitting adjusts the four offsets around a fixed centre, which is only
 	# meaningful for a card pinned to a point - both anchor pairs collapsed,
 	# as a centred dialog's are. A panel stretched between different anchors
diff --git a/ui/TouchJoystick.gd b/ui/TouchJoystick.gd
index 78056a6..a16c48e 100644
--- a/ui/TouchJoystick.gd
+++ b/ui/TouchJoystick.gd
@@ -1,3 +1,4 @@
+@tool
 class_name TouchJoystick
 extends Control
 
@@ -40,6 +41,11 @@ var knob_pos: Vector2 = Vector2.ZERO
 
 
 func _ready() -> void:
+	# _relayout() writes max_radius, which is @export - under @tool that
+	# would persist a computed value into the scene. The preview uses the
+	# authored radius instead; only a running game refits.
+	if Engine.is_editor_hint():
+		return
 	# Dialogs release every spring-loaded stick through one compositional
 	# contract, without NarrationBanner knowing scene paths or joystick roles.
 	add_to_group("touch_joysticks")