diff --git a/tests/test_custom_provider.py b/tests/test_custom_provider.py
new file mode 100644
index 0000000..463affe
--- /dev/null
+++ b/tests/test_custom_provider.py
@@ -0,0 +1,13 @@
+from types import SimpleNamespace
+
+from nanobot.providers.custom_provider import CustomProvider
+
+
+def test_custom_provider_parse_handles_empty_choices() -> None:
+    provider = CustomProvider()
+    response = SimpleNamespace(choices=[])
+
+    result = provider._parse(response)
+
+    assert result.finish_reason == "error"
+    assert "empty choices" in result.content