diff --git a/vpp-api-test/vat/api_format.c b/vpp-api-test/vat/api_format.c
index 0fb7d1f..666a4bd 100644
--- a/vpp-api-test/vat/api_format.c
+++ b/vpp-api-test/vat/api_format.c
@@ -2122,6 +2122,8 @@
     gpe_status = format (0, "%s", mp->gpe_status ? "enabled" : "disabled");
     feature_status = format (0, "%s",
                             mp->feature_status ? "enabled" : "disabled");
+    vec_add1 (gpe_status, 0);
+    vec_add1 (feature_status, 0);
 
     if (VAT_JSON_ARRAY != vam->json_tree.type) {
         ASSERT(VAT_JSON_NONE == vam->json_tree.type);