Last I worked with fossil, their main UI for issues/wikis was all through the web-ui. It works, but it's not as streamlined as you might like. If you're looking into fossil and want an alternative interface then it's mostly up to you to either build something out of command or more easily build something out of direct queries to the sqlite database that info is stored in. I didn't see many examples of either out there when I was looking last, though I did try building something along those lines ( https://github.com/fundamental/fs-tickets ).
Unless the ticket subcommand has been radically redesigned it is very clunky to use. Some of my complaints when I used the CLI last: Multiple runs of it with long parameter list are needed to navigate. Updates involving copying a UUID is a slow process. Updates commands to add comments, change ticket state, add files, etc are unintuitive. Listing ticket information does not nicely fit the dimensions of a terminal. Colorization does not appear to render in a terminal. No input validation. Cryptic documentation per sub-command.
As per the JSON API and TH scripting, they're both for the web UI (AFAIK) which I was trying to avoid if possible as it slowed down my overall workflow (though much more time has been put into making that usable by the fossil devs). As a last note TH is a bit of an oddity which I imagine may be a turn-off to other people getting started with tweaking fossil.
