/api/editSlaveMeta allows you to attach arbitrary metadata to slaves

You will need its unique ID and rcon password though.

package.json

@@ -16,6 +16,7 @@
     "body-parser": "^1.15.2",
     "canvasjs": "^1.8.1",
     "child_process": "^1.0.2",
+    "deepmerge": "^1.3.2",
     "ejs": "^2.5.6",
     "express": "^4.14.0",
     "express-fileupload": "0.0.6",