The way I understand the Terms of Service is that the only 3rd party software that is against the rules is that which manipulates the environment, changes the way the mechanics of the game are intended to work, exploits a glitch in the programming, or negatively impacts the community. Fishing bots, farming bots, gil or item "duping", and "teleport" hacks used to move instantaneously from one place to another in a field would be examples. Things like parsers that access game data but don't manipulate it are okay. As are things like programmable hardware devices, as long as you aren't using it to do something that violates the ToS.