diff --git a/tests/integration/test_cli_parser_defaults.py b/tests/integration/test_cli_parser_defaults.py
new file mode 100644
index 00000000..d94fdf74
--- /dev/null
+++ b/tests/integration/test_cli_parser_defaults.py
@@ -0,0 +1,14 @@
+from __future__ import annotations
+
+from openamp_foundry.cli.main import build_parser
+
+
+def test_rank_parser_defaults_are_stable():
+    parser = build_parser()
+    args = parser.parse_args(["rank", "--candidates", "candidates.csv", "--out", "ranked.jsonl"])
+
+    assert args.command == "rank"
+    assert args.references is None
+    assert args.config == "configs/pipeline.yaml"
+    assert args.ranking_mode == "ensemble"
+    assert args.simulation_mode == "off"