Reports, not detection
The usual route to an account being looked at is another player reporting it. Picking fights with an active, organised tribe raises your risk far more than anything technical does.
The question everybody asks first
No - it is against the rules, and almost nobody is banned for it. Both of those are true at once, and you deserve the whole picture rather than half of it.
The short answer
The Tribal Wars rules forbid playing by script. That covers this add-on and every other one, free or paid, and nobody can sell you an exemption from it.
What happens in practice is a different question, and it is the one you are actually asking. Automation is widespread on most worlds, including among players who pay for premium, and enforcement is light. Action almost always follows a player reporting you, not the game noticing by itself.
So the honest answer is: a real but small risk, mostly in your own hands. The rest of this page is what moves it up and down, and the commercial terms are in the terms of service.
How it actually works
Worth knowing before you decide, and nobody in this market says it out loud.
The usual route to an account being looked at is another player reporting it. Picking fights with an active, organised tribe raises your risk far more than anything technical does.
The German worlds are the ones to be careful on: it is InnoGames' home market and the largest, and it gets the most attention. The English, Dutch and smaller markets are noticeably more relaxed.
Perfect intervals around the clock, a farm run landing on the same second every hour, a village that has visibly never slept. Behaviour a neighbour can spot from the outside is what starts the chain.
Where action is taken it tends to land on the game account, not on anything else of yours. Your Tribal Works licence is separate from it and is not affected either way.
How Tribal Works plays
Most of what gets a village noticed is the giveaway kind of behaviour above, so that is what the add-on is built not to produce.
Intervals vary, nothing lands on the same second twice, and the pace follows hours a person would keep instead of running flat out around the clock.
It runs in your own browser, so it needs the game tab open on a machine that stays on - a desktop left running, or a cheap VPS. Give it that and it farms, builds and dodges through the night without you.
When the game puts one up, everything halts and an alarm rings in your tab. It never tries to solve one, which also means it never blunders through a check and leaves a trail doing it.
Two tabs open cannot both spend the same resources or send the same troops, so your account never does two contradictory things a second apart.
It works inside the game tab you are already signed in to. There is nothing to type a game password into, so there is nothing of yours for us to hold.
The log says what it did and why, and any decision can be overruled with a click - so if something looks unlike you, you can see it and change it.
In short
A small chance of losing a game account, against a village that keeps farming, building and dodging while you are at work or asleep. Most people who look at that trade take it, and most of them carry on playing for years.
We would rather you decided that with the real picture in front of you than with either the scare stories or the sales pitch. If you want to try it against what you are using now, the trial is three days with everything switched on and no card.
Nothing here is legal advice, and nothing here changes the game operator's rules or what they may choose to do about an account.
Asked straight after
Yes - an account can be banned for it, because automation is against the rules and the operator is entitled to act. In practice it is uncommon, and it usually starts with another player reporting you rather than with the game spotting anything by itself.
The German ones. It is InnoGames' home market and the biggest, so it gets the most attention. English, Dutch and the smaller markets are noticeably more relaxed.
No. It stops at one, rings an alarm in your tab and waits for you. That is deliberate: a bot that tries to push through a check is exactly the kind that gets an account looked at.
Yes, as long as the machine stays on with the game tab open - it does not have to be the tab you are looking at. A desktop left running overnight or a cheap VPS is all it takes. Shutting the machine down stops it.
The behaviour that gets villages noticed is clockwork timing, pushing through checks and acting from several tabs at once, and this one is built to do none of those. We are not going to put a number on it, because nobody honestly can.
No, and we do not sell it as hidden. What it does is play in a way that does not stand out, which is a different thing and the only one anybody can actually deliver.
The licence is for the add-on rather than for your game account, so it carries on and is not something we can refund for. You can use it on a new account or a new world straight away. The refunds page says it plainly.
Three days, everything switched on, no card. If it does less than what you are already using, you have lost nothing.
See what it costs