friendica/mod/rsd_xml.php

<?php

use Friendica\App;
use Friendica\Core\System;

function rsd_xml_content(App $a)
{
	header ("Content-Type: text/xml");
	echo '<?xml version="1.0" encoding="UTF-8"?>
<rsd version="1.0" xmlns="http://archipelago.phrasewise.com/rsd">
  <service>
    <engineName>Friendica</engineName>
    <engineLink>http://friendica.com/</engineLink>
    <apis>
      <api name="Twitter" preferred="true" apiLink="'.System::baseUrl().'/api/" blogID="">
        <settings>
          <docs>http://status.net/wiki/TwitterCompatibleAPI</docs>
          <setting name="OAuth">false</setting>
        </settings>
      </api>
    </apis>
  </service>
</rsd>';

	exit();
}