I see the server now has an official API and would like to suggest an endpoint to check the balance of a player. Also it would be nice to have a guide on request limits so ppl don't abuse the system and ruin it for the rest of us.
I have asked Dex and Matt about this in the past, and is a possibility. EDIT: To be more specific, the API is, currently, purely for the servers' needs and not as a public API.
Currently the public API is only for global data (like the trades) and not intended for user specific data. If this gets implemented it won't be any time soon unfortunately since the public API isn't really a priority for us.
There's also unofficial api endpoints which don't really have a list but are implemented here if you want to see them.
Those endpoints are not a part of the official API so you can't rely on them. We use them for our front-end and discord bot. If they are being misused in the future we'll have to make them inaccessible.
Would be best if you'd post a separate suggestion thread for that, since the shop data is global it might get added but can't promise it at this time.
If you wanted to be malicious, you could use an ingame bot which would be easier to track "when they are afk and when they are building stuff.", though I don't know how a balance endpoint could lead to either of these things being tracked.