I recently ran in to a problem where i couldnt delete an NSX segment so i went exploring the API. The API guide can be found here

The method used is delete policy/api/v1/infra/segments/{segment-id}?force=true

It would look like this in Postman:

DELETE request for NSX-T 3 segment deletion with “force=true” query param.

To list the segments we can use a get request towards /policy/api/v1/infra/segments/

API request setup for listing NSX-T 3 segments in Postman.