diff --git a/clusters/tool.json b/clusters/tool.json
index 54fbad3..ee6d68a 100644
--- a/clusters/tool.json
+++ b/clusters/tool.json
@@ -1139,7 +1139,7 @@
           "Phindolp",
           "BS2005"
         ],
-        "refs":[
+        "refs": [
           "https://github.com/nccgroup/Royal_APT"
         ]
       },