The GoSweetSpot REST API can be used to programmatically access the system on behalf of a user.
You can get a user's API key from a specific user's page by navigating from the user's screen.
Only one API key can be set up per user. You can regenerate the key at any time.
Any settings related to the user account (e.g. Origin location, Printer Preference) will apply to actions executed through the API. If your company has multiple locations configured, your user account needs to have only one location selected to access the API. You can do this from Manage Users.
Full documentation can be found here: https://github.com/gosweetspot/freight-api
C# API Client: https://www.nuget.org/packages/GoSweetSpot.ApiClient/