As stated in other sections, CoW Protocol works with signed messages instead of executing transactions on the go. This means, that on the UI, the user sees a price quote that is based on an estimation of what prices will that particular order be settled with. One particular feature of CoW Protocol is that within the price estimation, it shows "the minimum amount to be received" which is a price quote that can't be violated, meaning that the protocol will either give you that price or the order will expire and be canceled without any cost. Although, if through CoWs, the protocol can offer you a better quote than the minimum received, it will execute your order with a surplus. In other words, price estimation is a lower bound on the proceeds a user can get for their trade. While we are working on it, at the moment slippage is not yet included in the price estimate