...
Email sales@desktopshipper.com to get an API token.
Once you have received your token, you must Authorize it through DesktopShipper:. Login to your DesktopShipper account.
...
Click on the green Authorize button at the top of the page.
In the window that shows up, under Bearer, enter "Bearer {token}" into the textbox. For example if your token is "1234" enter " Bearer 1234". Then click "Authorize".
If you ever need to view your API token again, navigate to “Manage your Users” → “API”
...