diff --git a/src/core/move_generator.gd b/src/core/move_generator.gd
index eea2fcb..381ab07 100644
--- a/src/core/move_generator.gd
+++ b/src/core/move_generator.gd
@@ -16,10 +16,12 @@ static func generate(hand: Array[Card], current_rank: int, config: RuleConfig) -
     results.append(pass_play)
     if hand.is_empty():
         return results
-    var sorted := hand.duplicate(false)
+    var sorted: Array[Card] = []
+    for item: Card in hand:
+        sorted.append(item)
     _sort(sorted)
     var seen_ranks := {}
-    for c in sorted:
+    for c: Card in sorted:
         var rk := c.rank()
         if seen_ranks.get(rk, 0) < 4:
             var ep := HandEvaluator.evaluate([c], current_rank, config)
diff --git a/src/game/game_controller.gd b/src/game/game_controller.gd
index 1faf97e..7d637d5 100644
--- a/src/game/game_controller.gd
+++ b/src/game/game_controller.gd
@@ -94,11 +94,11 @@ func _next_alive_player() -> void:
             return
 
 func _trigger_ai(player_idx: int) -> void:
-    var ai := ai_players.get(player_idx)
+    var ai: BaseAI = ai_players.get(player_idx) as BaseAI
     if ai == null:
         return
     var hand8: Array = game_state.get_hand(player_idx)
-    var decision := ai.decide(hand8, game_state.round.table, game_state.current_rank, game_state.rule_config)
+    var decision: HandEvaluator.EvaluatedPlay = ai.decide(hand8, game_state.round.table, game_state.current_rank, game_state.rule_config)
     if decision.type == -1:
         _apply_play(player_idx, decision)
     else:
diff --git a/src/ui/components/card_node.gd b/src/ui/components/card_node.gd
index 4bcbad4..6039156 100644
--- a/src/ui/components/card_node.gd
+++ b/src/ui/components/card_node.gd
@@ -1,8 +1,8 @@
 class_name CardNode
 extends Control
 
-signal card_clicked(card_node)
-signal card_double_clicked(card_node)
+signal card_clicked(card_node: CardNode)
+signal card_double_clicked(card_node: CardNode)
 
 var card_data: Card = null
 var is_selected: bool = false
@@ -11,28 +11,28 @@ var is_selected: bool = false
 @onready var label: Label = $Label
 
 func setup(card: Card) -> void:
-	card_data = card
-	update_display()
+    card_data = card
+    update_display()
 
 func update_display() -> void:
-	if card_data == null:
-		return
-	var suits := ["S", "H", "C", "D", "SJ", "BJ"]
-	var ranks := ["", "", "2", "3", "4", "5", "6", "7", "8", "9", "10", "J", "Q", "K", "A", "SJ", "BJ"]
-	var suit := card_data.suit()
-	var rank := card_data.rank()
-	if rank < ranks.size() and suit < suits.size():
-		label.text = "%s %s" % [suits[suit], ranks[rank]]
-	modulate = Color.WHITE if not is_selected else Color(1.2, 1.2, 0.8)
+    if card_data == null:
+        return
+    var suits := ["S", "H", "C", "D", "SJ", "BJ"]
+    var ranks := ["", "", "2", "3", "4", "5", "6", "7", "8", "9", "10", "J", "Q", "K", "A", "SJ", "BJ"]
+    var suit := card_data.suit()
+    var rank := card_data.rank()
+    if rank < ranks.size() and suit < suits.size():
+        label.text = "%s %s" % [suits[suit], ranks[rank]]
+    modulate = Color.WHITE if not is_selected else Color(1.2, 1.2, 0.8)
 
 func set_selected(sel: bool) -> void:
-	is_selected = sel
-	update_display()
+    is_selected = sel
+    update_display()
 
 func _on_gui_input(event: InputEvent) -> void:
-	if event is InputEventMouseButton:
-		if event.button_index == MOUSE_BUTTON_LEFT and event.pressed:
-			if event.double_click:
-				card_double_clicked.emit(self)
-			else:
-				card_clicked.emit(self)
+    if event is InputEventMouseButton:
+        if event.button_index == MOUSE_BUTTON_LEFT and event.pressed:
+            if event.double_click:
+                card_double_clicked.emit(self)
+            else:
+                card_clicked.emit(self)
diff --git a/src/ui/components/hand_area.gd b/src/ui/components/hand_area.gd
index 61848be..4f3fce3 100644
--- a/src/ui/components/hand_area.gd
+++ b/src/ui/components/hand_area.gd
@@ -18,7 +18,7 @@ func update_hand(hand: Array) -> void:
     card_nodes.clear()
     selected_cards.clear()
     for c in hand:
-        var node: CardNode = CARD_SCENE.instantiate()
+        var node := CARD_SCENE.instantiate() as CardNode
         node.setup(c)
         node.card_clicked.connect(_on_card_clicked)
         node.card_double_clicked.connect(_on_card_double_clicked)
@@ -40,23 +40,23 @@ func _on_card_double_clicked(card_node: CardNode) -> void:
     play_requested.emit()
 
 func _on_hint_pressed() -> void:
-	hint_requested.emit()
+    hint_requested.emit()
 
 func _on_play_pressed() -> void:
-	play_requested.emit()
+    play_requested.emit()
 
 func _on_pass_pressed() -> void:
-	pass_requested.emit()
+    pass_requested.emit()
 
 func disable_input() -> void:
-	for cn in card_nodes:
-		cn.mouse_filter = Control.MOUSE_FILTER_IGNORE
+    for cn in card_nodes:
+        cn.mouse_filter = Control.MOUSE_FILTER_IGNORE
 
 func enable_input() -> void:
-	for cn in card_nodes:
-		cn.mouse_filter = Control.MOUSE_FILTER_STOP
+    for cn in card_nodes:
+        cn.mouse_filter = Control.MOUSE_FILTER_STOP
 
 func clear_selection() -> void:
-	for cn in card_nodes:
-		cn.set_selected(false)
-	selected_cards.clear()
+    for cn in card_nodes:
+        cn.set_selected(false)
+    selected_cards.clear()