docs: protected OptionalThing<Supplier<String>> extractRemoteApiCounter() {
          final Supplier<String> counter = ThreadCacheContext.getObject("fw:remoteApiCounter"); // expectes LastaFlute-1.0.1
          return OptionalThing.ofNullable(counter, () -> {
              throw new IllegalStateException("Not found the remote-api counter in the thread cache.");
          });
      }