A discussion is one conversation with a room of AIs instead of a single model. You ask a question or describe something to build; the seats in the room work on it together and hand you one agreed answer.
Who does what
One seat leads. It answers first, and on the Mac it is the one that changes files. The other seats review: each reads what the lead did and says what is wrong, what is missing, or that it agrees. On the Mac a reviewer does not take the lead's word — it runs its own commands (the build, the tests, whatever settles the question), and its verdict carries the commands it ran and whether they passed.
Rounds
A round is one pass by every seat. When a reviewer fully endorses the work it ends its turn with an agree token; once every reviewer has agreed, the lead writes up the final answer and the discussion stops. If they have not agreed by the round limit, the discussion stops there and shows you where it got to. You can then follow up, or press Keep improving to give the room more rounds.
The default is Until they agree: the room runs as far as your plan allows and stops the moment everybody agrees. The Free plan allows up to three rounds per message; Pro and Team allow up to six. Because the early stop is the real brake, a straightforward question still finishes in about two rounds — the extra ones are only spent where the room genuinely has not settled. Pick a number in Settings to stop it sooner.
Reading the result
Under an answer you will see how many reviewers agreed and, on the Mac, a receipt of how many commands ran and how many passed. A reviewer that agreed without opening a file or running a command says so — that is a weaker review than one that checked, and the app tells you rather than hiding it.
Every discussion is also a ticket with a key like LTB-12, a stage on the board, and a place in a project; see "Every discussion is a ticket".