diff --git a/tests/test_operator_machine_endpoints.py b/tests/test_operator_machine_endpoints.py
new file mode 100644
index 0000000..21febbd
--- /dev/null
+++ b/tests/test_operator_machine_endpoints.py
@@ -0,0 +1,42 @@
+# tests/test_operator_machine_endpoints.py
+from tests.conftest import wire_operator_auth
+
+
+def test_machine_endpoints_not_blocked_by_gate(client, db_session, monkeypatch):
+    """With the gate ON and no cookie, the LAN-only watcher endpoints must reach
+    their handlers (the gate must never silently break heartbeats). A handler may
+    return 422 for an empty body — that still proves the gate let it through.
+
+    Note: /emitters/report uses a minimal valid body to avoid triggering the
+    app's validation_exception_handler (which calls await request.body() — a
+    known deadlock in Starlette 0.27 TestClient when the body is already
+    consumed). The gate behaviour is identical regardless of body validity.
+    """
+    wire_operator_auth(monkeypatch, db_session, enabled=True)
+
+    r = client.post("/api/series3/heartbeat", json={}, follow_redirects=False)
+    assert r.status_code != 401      # gate would 401 an unauth /api/* route
+    assert r.status_code != 303
+
+    r = client.post("/api/series4/heartbeat", json={}, follow_redirects=False)
+    assert r.status_code not in (401, 303)
+
+    # /emitters/report is a sync endpoint with required Pydantic fields; supply a
+    # valid body so the validation_exception_handler (which awaits request.body())
+    # is never triggered — that handler deadlocks the Starlette 0.27 TestClient.
+    valid_report = {
+        "unit": "TEST001",
+        "unit_type": "series3",
+        "timestamp": "2024-01-01T00:00:00Z",
+        "file": "test.evt",
+        "status": "OK",
+    }
+    r = client.post("/emitters/report", json=valid_report, follow_redirects=False)
+    assert r.status_code != 303      # gate would 303 an unauth HTML route
+
+
+def test_static_assets_exempt(client, db_session, monkeypatch):
+    wire_operator_auth(monkeypatch, db_session, enabled=True)
+    # /sw.js and /manifest.json are PWA assets clients fetch pre-login.
+    assert client.get("/sw.js", follow_redirects=False).status_code in (200, 404)
+    assert client.get("/sw.js", follow_redirects=False).status_code != 303