HTTP请求没有得到响应

我正在尝试发送一个HTTP请求的形式:

GET /api/content/v1/parser?url=http://blog.readability.com/2011/02/step-up-be-heard-readability-ideas/&token=1b830931777ac7c2ac954e9f0d67df437175e66e

我想联系的网站是www.readability.com

我一直在尝试使用以下请求:

string readabilityUrl = "http://www.readability.com";
string requestUrl = createRequestUrl(articleUrl);
// Create http request send to readability api
System.Diagnostics.Debug.WriteLine(readabilityUrl + requestUrl);
var request = (HttpWebRequest)WebRequest.Create(readabilityUrl);
var postData = requestUrl;
var postReqData = Encoding.ASCII.GetBytes(postData);
request.Method = "POST";
using (var stream = request.GetRequestStream())
{
    stream.Write(postReqData, 0, postReqData.Length);
}
var response = (HttpWebResponse)request.GetResponse();
var responseString = new StreamReader(response.GetResponseStream()).ReadToEnd();
System.Diagnostics.Debug.WriteLine(responseString);

但是它所做的只是获取www.readaility.com的html内容，而不是返回我实际需要的相关数据。

我想我没有发送正确的参数，如果你能帮助我，并指出我的解决方案，我将不胜感激。