diff --git a/tests/test_app.py b/tests/test_app.py
index a3ea996..cf541dd 100644
--- a/tests/test_app.py
+++ b/tests/test_app.py
@@ -277,6 +277,13 @@ def test_dns_rrset_dry_run_returns_only_selected_records(monkeypatch):
     assert body["deleted"] == []
 
 
+def test_hetzner_dns_token_accepts_single_sanitized_vault_alias(monkeypatch):
+    monkeypatch.setattr(app, "_vault_cache", {"hetzner-dns-api": "secret-value", "other": "ignored"})
+    monkeypatch.setattr(app, "_read", lambda _name: None)
+    monkeypatch.setattr(app, "_ssh", lambda *_args, **_kwargs: (_ for _ in ()).throw(AssertionError("must not sync vault")))
+    assert app._get_hetzner_dns_token() == "secret-value"
+
+
 def test_invalid_log_target_is_rejected_before_ssh():
     with TestClient(app.app) as client:
         response = client.get(