diff --git a/tests/test_phase3f_cleanup_contracts.py b/tests/test_phase3f_cleanup_contracts.py
index 69c6b7c..c071d60 100644
--- a/tests/test_phase3f_cleanup_contracts.py
+++ b/tests/test_phase3f_cleanup_contracts.py
@@ -57,6 +57,12 @@ def test_phase3f_orphan_ai_services_stay_removed():
     assert [path for path in orphan_services if (ROOT / path).exists()] == []
 
 
+def test_app_py_stays_blueprint_only_for_routes():
+    app_source = (ROOT / "app.py").read_text(encoding="utf-8")
+
+    assert "@app.route" not in app_source
+
+
 def test_active_guides_do_not_point_to_removed_ai_services():
     active_guides = [
         ROOT / "docs" / "ELEPHANT_ALPHA_SETUP.md",