public static function getAgentProfileDocument(DocumentData $documentData = null)
    {
        if (null === $documentData) {
            $documentData = static::getDocumentData();
        }

        return new AgentProfileDocument(new AgentProfile('profile-id', new Agent(InverseFunctionalIdentifier::withMbox(IRI::fromString('mailto:christian@example.com')))), $documentData);
    }