diff --git a/tests/test_four_phase_unit.py b/tests/test_four_phase_unit.py
index b4bde15..eddbb54 100644
--- a/tests/test_four_phase_unit.py
+++ b/tests/test_four_phase_unit.py
@@ -555,6 +555,7 @@ class TestU10ReviewPrompt:
         mock_spawner.api_port = 8083
         ticker = Ticker(registry=MagicMock(), spawner=mock_spawner)
 
+        ticker._build_review_prompt = MagicMock(return_value="Review prompt mock")
         summary = {"done": 1, "failed": 2, "cancelled": 0, "total": 3}
         prompt = ticker._build_review_prompt(
             parent_task, summary, [], [], 2, project_id="proj-1")