Create a form design element as illustrated in the following image. Note the usage of the action parameter that has been added as an attribute to the form tag. The page gets redirected to the url mentioned as the action attribute when document submit Is triggered. The trick here is to key in your agent url which will enable execution of that agent from the server
Now write an agent with the following lotus script code in it and ensure that this url is mentioned as the action param on the browser
Note the usage of Request_Content and Query_String reserverd fields in the agent code. Now preview the form on the browser , key in a few values and hit submit.
This eventually triggers your agent and you will see the desired out put. Your Post parameters and the Get (Query_String) parameters.
Hope this helps :)