diff --git a/ocr-service/test_sender_registry.py b/ocr-service/test_sender_registry.py
index e5a7c97d..7cf7cd24 100644
--- a/ocr-service/test_sender_registry.py
+++ b/ocr-service/test_sender_registry.py
@@ -63,3 +63,13 @@ def test_path_outside_models_dir_raises():
     registry = _make_registry()
     with pytest.raises(ValueError, match="not allowed"):
         registry.get_model("/etc/passwd")
+
+
+def test_load_failure_does_not_cache_broken_entry():
+    """A failed load must not leave a broken entry in the cache."""
+    registry = _make_registry()
+    with patch("engines.kraken._load_sender_model", side_effect=RuntimeError("corrupt model")):
+        with pytest.raises(RuntimeError, match="corrupt model"):
+            registry.get_model("/app/models/sender_bad.mlmodel")
+
+    assert registry.size() == 0