2Shakes has standard IR authority wording.
To access any information held by Inland Revenue Department of New Zealand about all tax types (except child support) in order for them to undertake their duties until further notice. They are authorised to obtain information through all Inland Revenue media and communication channels including phone or fax or online, to request to receive correspondence related to tax types, to modify tax details, to prepare, submit and sign tax returns on your behalf.
You can alter the authority wording in your Business Profile to suit your circumstances.