Most importantly, polish the tool.

I'm not going to get my boss to pay for something that is made out of duct tape. If you want to sell something to people who probably know how to build it themselves, you need to impress them with something shiny. While it should work perfectly most of the time, it should also come with helpful error messages when it doesn't like the input. If I come across some cryptic, ungooglable internal error or access violation or assertion where I'd have to contact support to even understand what's wrong, I'd rather delete your tool immediately.