How should we handle the case of “N/A” in the API for description of goods and services?

In the API class 46 stands for "Not Applicable". If you have a registered trademark where a NICE class does not apply you can use class 46 to indicate this.

FAQ

API (Automated Interface)

billing

Brandpulse

correction process

documentary evidence

general

invoicing

Mark Record Transfer

mark record verification

New gTLD program

Notifications

official agents

online payment

OT&E

prepayment account

pricing

proof of use

Registrars

Registries

Renewal

Signed Mark Data (SMD)

Strawman Model - Abused Labels

Sunrise Services

support

trademark claims services

Trademark Eligibility Requirements

trademark submission

TREx Service

user registration