docs: function whatis(uuid, cb) {
      assert.string(uuid, 'uuid');
      assert.func(cb, 'cb');
  
      var self = this;
  
      async.waterfall([
          function (subcb) {
              self.getApplication(uuid, function (err, app) {
                  if (err && err.statusCode !== 404)
                      return (cb(err));
                  if (app) {
                      app.type = 'application';
                      return (cb(null, app));
                  }
  
                  return (subcb(null));
              });
          },
          function (subcb) {
              self.getService(uuid, function (err, svc) {
                  if (err && err.statusCode !== 404)
                      return (cb(err));
                  if (svc) {
                      svc.type = 'service';
                      return (cb(null, svc));
                  }
  
                  return (subcb(null));
              });
          },
          function (subcb) {
              self.getInstance(uuid, function (err, inst) {
                  if (err && err.statusCode !== 404)
                      return (cb(err));
                  if (inst) {
                      inst.type = 'instance';
                      return (cb(null, inst));
                  }
  
                  return (subcb(null));
              });
          }
      ], function () {
          cb(null, null);
      });
  }