The response to a HTTP method is deserialized and bound to a dynamic object by default. The dynamic object can be cast to a static object if required See Casting.
dynamic client = new RestClient("https://jsonplaceholder.typicode.com"); var user = await client.Users.Get(1); Assert.That(user.id, Is.EqualTo(1));
The variable user represents a user object with the properties and values returned from GET https://jsonplaceholder.typicode.com/users/1
Note by default dynamic binding only works for JSON content, however it is easy to extend using your own handler, see pipeline and handers