$agi->get_variable('CALLERID(num)') return empty

Asterisk Asterisk APIs
1

Hello people.

I’ve this script

#!/usr/bin/php -q
<?php 

require('phpagi.php');
require('conexion.php');

$agi = new AGI();

$agi->answer();

$callerid = $agi->get_variable('CALLERID(num)'); 
$agi->exec("NOOP", $callerid['data']);
$agi->verbose($callerid);
$agi->hangup();

?>

and then returns this and I do not understand why. Please help.

 Executing [3000@from-internal:1] AGI("SIP/4001-00000025", "conectar_llamada.php") in new stack
    -- Launched AGI Script /var/lib/asterisk/agi-bin/conectar_llamada.php
    -- AGI Script Executing Application: (NOOP) Options: ()
 conectar_llamada.php: Array
 conectar_llamada.php: (
 conectar_llamada.php:     [code] => 200
 conectar_llamada.php:     [result] => 0
 conectar_llamada.php:     [data] => 
 conectar_llamada.php: )
 conectar_llamada.php: 
    -- <SIP/4001-00000025>AGI Script conectar_llamada.php completed, returning 4
  == Spawn extension (from-internal, 3000, 1) exited non-zero on 'SIP/4001-00000025'
2

Based on the documentation [‘result’] is 0 if variable hasn’t been set, 1 if it has. [‘data’] holds the value. any way you can pass the CallerID num variable to your php scripting using the array $argv