problemi con phpdoc 2

[astros3]

Installazione

$ wget http://www.phpdoc.org/phpDocumentor.phar
$ chmod +x phpdocumentor.phar

$ cat src/Classe.php
<?php
/**
 * Sommario Classe.php
 */

/**
 * Classe.
 */
class Classe {}

$ ./phpdocumentor.phar -f src/Classe.php
Collecting files .. OK
Initializing parser .. OK
Parsing files
blablabla...

Tutto OK.

$ cat src/fun.php
<?php
/**
 * Sommario fun.php
 */

/**
 * Funzione.
 */
function fun() {}

$ ./phpdocumentor.phar -f src/fun.php
Collecting files .. OK
Initializing parser .. OK
Parsing files
blablabla...
PHP Warning:  count(): Parameter must be an array or an object that implements Countable in phpDocumentor.phar/vendor/twig/twig/lib/Twig/Extension/Core.php on line 1293
PHP Warning:  count(): Parameter must be an array or an object that implements Countable in phpDocumentor.phar/vendor/twig/twig/lib/Twig/Extension/Core.php on line 1293
  Execute transformation using writer "twig"
PHP Warning:  count(): Parameter must be an array or an object that implements Countable in phpDocumentor.phar/vendor/twig/twig/lib/Twig/Extension/Core.php on line 1293
PHP Warning:  count(): Parameter must be an array or an object that implements Countable in phpDocumentor.phar/vendor/twig/twig/lib/Twig/Extension/Core.php on line 1293
  Execute transformation using writer "twig"
  Execute transformation using writer "twig"
  Execute transformation using writer "twig"
  Execute transformation using writer "twig"
PHP Warning:  count(): Parameter must be an array or an object that implements Countable in phpDocumentor.phar/vendor/twig/twig/lib/Twig/Extension/Core.php on line 1293
PHP Warning:  count(): Parameter must be an array or an object that implements Countable in phpDocumentor.phar/vendor/twig/twig/lib/Twig/Extension/Core.php on line 1293
blablabla...

Adesso invece ci sono degli errori (Warning).
Perchè?

Ho anche provato a installare phpdoc tramite composer

$ composer require --dev phpDocumentor/phpDocumentor
blablabla...
Package kherge/version is abandoned, you should avoid using it. No replacement was suggested.
Package herrera-io/json is abandoned, you should avoid using it. Use kherge/json instead.
Package herrera-io/phar-update is abandoned, you should avoid using it. No replacement was suggested.
Writing lock file
Generating autoload files

Ma il risultato è ancora peggiore

$ vendor/bin/phpdoc -f src/Classe.php 
PHP Fatal error:  Uncaught Doctrine\Common\Annotations\AnnotationException: [Semantical Error] The annotation "@JMS\Serializer\Annotation\Type" in property phpDocumentor\Configuration::$title does not exist, or could not be auto-loaded. in vendor/doctrine/annotations/lib/Doctrine/Common/Annotations/AnnotationException.php:54
Stack trace:
#0 vendor/doctrine/annotations/lib/Doctrine/Common/Annotations/DocParser.php(741): Doctrine\Common\Annotations\AnnotationException::semanticalError('The annotation ...')
#1 vendor/doctrine/annotations/lib/Doctrine/Common/Annotations/DocParser.php(663): Doctrine\Common\Annotations\DocParser->Annotation()
#2 vendor/doctrine/annotations/lib/Doctrine/Common/Annotations/DocParser.php(354): Doctrine\Common\Annotations\DocParser->Annotations()
#3 vendor/doctrine/annotations/lib/Doctrine/Common/Annotations/AnnotationReader.php(254): Doctrine\Common\Annotations\Doc in vendor/doctrine/annotations/lib/Doctrine/Common/Annotations/AnnotationException.php on line 54

A questo punto vorrei sapere, questo phpdoc è uno strumento valido?
Sono io che non lo so usare?
Cosa c'è che non va?