title: Changing agi parameters before calling the script
body: <p>I was wondering: is there a way to change the values of the agi parameters before calling the script?</p>
  
  <p>In particular, I need to change the <code>agi_channel</code> to a custom value.</p>
  
  <p>Is it possible?</p>
  
  <p>Thanks in advance.</p>