diff --git a/tests/test_planner_hierarchy.py b/tests/test_planner_hierarchy.py
new file mode 100644
index 0000000..9e60270
--- /dev/null
+++ b/tests/test_planner_hierarchy.py
@@ -0,0 +1,63 @@
+import pytest
+from unittest.mock import patch
+from GramAddict.core.navigation.planner import GoalPlanner
+from GramAddict.core.perception.screen_identity import ScreenType
+
+@pytest.fixture
+def planner():
+    return GoalPlanner("test_user")
+
+@patch("GramAddict.core.navigation.brain.ask_brain_for_action")
+@patch("GramAddict.core.screen_topology.ScreenTopology.find_route")
+def test_brain_is_primary_strategy(mock_find_route, mock_ask_brain, planner):
+    """
+    TDD Proof: Brain must be evaluated BEFORE HD Map.
+    If Brain returns a valid action, HD Map should never be queried.
+    """
+    # 1. Setup State
+    goal = "open some screen"
+    screen = {
+        "screen_type": ScreenType.HOME_FEED,
+        "available_actions": ["action A", "action B"],
+        "context": {}
+    }
+    
+    # 2. Setup Mocks
+    mock_ask_brain.return_value = "action A" # Brain picks A
+    mock_find_route.return_value = [("action B", ScreenType.EXPLORE_GRID)] # HD Map would pick B
+    
+    # 3. Execute Planner
+    action = planner.plan_next_step(goal, screen)
+    
+    # 4. Assertions
+    assert action == "action A", "Planner did not use the Brain's action!"
+    mock_ask_brain.assert_called_once()
+    mock_find_route.assert_not_called() # Crucial: HD Map must be skipped entirely!
+
+@patch("GramAddict.core.navigation.brain.ask_brain_for_action")
+@patch("GramAddict.core.screen_topology.ScreenTopology.find_route")
+@patch("GramAddict.core.screen_topology.ScreenTopology.goal_to_target_screen")
+def test_brain_fallback_to_hd_map(mock_goal_target, mock_find_route, mock_ask_brain, planner):
+    """
+    TDD Proof: If Brain fails (returns None), Planner must fallback to HD Map.
+    """
+    # 1. Setup State
+    goal = "open explore screen"
+    screen = {
+        "screen_type": ScreenType.HOME_FEED,
+        "available_actions": ["action A", "action B"],
+        "context": {}
+    }
+    
+    # 2. Setup Mocks
+    mock_ask_brain.return_value = None # Brain fails or is confused
+    mock_goal_target.return_value = ScreenType.EXPLORE_GRID
+    mock_find_route.return_value = [("action B", ScreenType.EXPLORE_GRID)] # HD Map picks B
+    
+    # 3. Execute Planner
+    action = planner.plan_next_step(goal, screen)
+    
+    # 4. Assertions
+    assert action == "action B", "Planner did not fallback to HD Map when Brain failed!"
+    mock_ask_brain.assert_called_once()
+    mock_find_route.assert_called_once()