class User
{
    /**
     * @var string
     */
    public $name;
}
function getTypeNameFromAnnotation(string $className, string $propertyName): ?string
{
    $rp = new \ReflectionProperty($className, $propertyName);
    if (preg_match('/@var\s+([^\s]+)/', $rp->getDocComment(), $matches)) {
        return $matches[1];
    }
    
    return null;
}
    
echo getTypeNameFromAnnotation('User', 'name');
// string