code: String toUrl(Auth.UrlCodex urlCodex) {
          return new StringBuilder(authUrl)
                  .append(authUrl.contains("?") ? "&" : "?")
                  .append("client_id").append("=").append(urlCodex.encode(clientId))
                  .append("&").append("response_type").append("=").append("token")
                  .append("&").append("scope").append("=").append(scopesToString(urlCodex))
                  .toString();
      }
docs: Returns a URL representation of this request, appending the client ID and scopes to the original authUrl.