I want to use the ghostwriter/atprotocol library to access the BlueSky social API, but don’t know how to use it.Where are the Bluesky classes listed?

ghostwriter/atprotocol library

vender/autoload.php
index.php

<?php
ini_set('display_errors','1');
error_reporting(-1);
ini_set('xdebug.var_display_max_children', -1);
ini_set('xdebug.var_display_max_data', -1);
ini_set('xdebug.var_display_max_depth', -1);

require './vendor/autoload.php';
$bsky = new Bluesky(personalDataServer: 'https://bsky.social');

No error messages are shown.
I am not sure why no error message is shown.

For Usage,

$bsky = new Bluesky(personalDataServer: 'https://bsky.social');

but where in the code is the Bluesky class written?