public function __construct()
 {
     //todo use a custom wiki url?
     $this->wikiClient = MediawikiApiClient::factory(array('base_url' => 'http://en.wikipedia.org/w/api.php'));
     $this->htmlToMarkdown = new HTML_To_Markdown();
 }
 /**
  * @return MediawikiApiClient
  */
 private function getClient()
 {
     return MediawikiApiClient::factory(array('base_url' => self::baseurl));
 }
<?php

if (!file_exists(__DIR__ . '/vendor/autoload.php')) {
    die('You must run "composer install" first!');
}
require_once __DIR__ . '/vendor/autoload.php';
$client = \Guzzle\Service\Mediawiki\MediawikiApiClient::factory(array('base_url' => 'http://localhost/wiki/api.php'));
$actionListGenerator = new \Guzzle\Service\Mediawiki\ActionListGenerator($client);
$descriptionGenerator = new \Guzzle\Service\Mediawiki\ServiceDescriptionGenerator($client);
$actions = $actionListGenerator->generateList();
$json = $descriptionGenerator->build($actions);
file_put_contents(__DIR__ . '/build_output.json', $json);
echo $json;
 /**
  * @return MediawikiApiClient
  */
 private function getClient()
 {
     return MediawikiApiClient::factory(array('base_url' => "http://localhost/wiki/api.php"));
 }