The aim of the project was to make htty an incremental advance over curl by layering aspects of a browser UX on top of it. What you get with htty that curl doesn't give you is primarily a session, and consequently a history. The other features are icing on the cake.

In the near future, the difference will be more striking. The ability to parse and build requests on various media types will make htty even better at the tasks of both API exploration and HTML screen-scraping.