code: protected String getBridgeJsonRefinementSearch(String clientKey) {
      Request request = new Request();
      request.setIncludedNavigations(includedNavigations);
      request.setExcludedNavigations(excludedNavigations);
      request.setClientKey(clientKey);
      request.setCollection(collection);
      request.setArea(area);
      request.setRefinementQuery(query);
      request.setWildcardSearchEnabled(isWildcardSearchEnabled());
      request.setSecuredPayload(securedPayload);
      if (CollectionUtils.isNotEmpty(sort)) {
        for (Sort s : sort) {
          request.setSort(convertSort(s));
        }
      }
      request.setMatchStrategy(convertPartialMatchStrategy(matchStrategy));
      return requestToJson(request);
    }
docs: @param clientKey
  Your client key
  
  @internal