diff --git a/tests/tools/test_send_message_tool.py b/tests/tools/test_send_message_tool.py
index 12eb6c55b..058678d36 100644
--- a/tests/tools/test_send_message_tool.py
+++ b/tests/tools/test_send_message_tool.py
@@ -400,20 +400,21 @@ class TestSendToPlatformChunking:
 
 class TestSendToPlatformWhatsapp:
     def test_whatsapp_routes_via_local_bridge_sender(self):
-        async_mock = AsyncMock(return_value={"success": True, "platform": "whatsapp", "chat_id": "43121572348102@lid", "message_id": "abc123"})
+        chat_id = "test-user@lid"
+        async_mock = AsyncMock(return_value={"success": True, "platform": "whatsapp", "chat_id": chat_id, "message_id": "abc123"})
 
         with patch("tools.send_message_tool._send_whatsapp", async_mock):
             result = asyncio.run(
                 _send_to_platform(
                     Platform.WHATSAPP,
                     SimpleNamespace(enabled=True, token=None, extra={"bridge_port": 3000}),
-                    "43121572348102@lid",
+                    chat_id,
                     "hello from hermes",
                 )
             )
 
         assert result["success"] is True
-        async_mock.assert_awaited_once_with({"bridge_port": 3000}, "43121572348102@lid", "hello from hermes")
+        async_mock.assert_awaited_once_with({"bridge_port": 3000}, chat_id, "hello from hermes")
 
 
 class TestSendTelegramHtmlDetection: