docs: private String parseParams(ParameterSet params, JSONObject obj) throws Exception
      {
          String path = null;
          if (params.toArray().length != 1) {
              return "Incorrect number of arguments to @SnapshotScan (expects 1, received " +
                      params.toArray().length + ")";
          }
          Object first = params.toArray()[0];
          if (!(first instanceof String)) {
              return "First argument to @SnapshotScan must be a valid STRING path, instead was " +
                  first;
          }
          path = (String)first;
          if (path == null || path == "") {
              return "Provided path was null or the empty string";
          }
          // Dupe SNAPSHOTSCAN as the subselector in case we consolidate later
          obj.put("subselector", "SNAPSHOTSCAN");
          obj.put("interval", false);
          obj.put("path", path);
  
          return null;
      }