API Format tags
From Openprovider API documentation
Format specification > Tags
This parameter is optional and allows you to specify a specific tags for object
Array of arrays with members:
| key | The key of the tag. Allowed values: 'customer' | 
| value | The value of the tag. | 
Using PHP class
array(
  array(
    'key' => 'customer',
    'value' => 'companyA'
  ),
);
Raw XML
<tags>
   <array>
       <item><key>customer</key><value>companyA</value></item>
   </array>
</tags>