The visit Knecht Ruprecht makes alongside Saint Nicholas on the evening of December fifth, ahead of the saint's own feast day on the sixth, follows a fairly consistent shape across the regions of central and southern Germany where the custom is kept. Nicholas, dressed as a bishop, arrives first and asks the household's children whether they have said their prayers and behaved through the year; Ruprecht, walking behind him in a dark, worn robe and often carrying a stick, a birch switch, or a bag of ashes, is the one who presses the point further, sometimes questioning the children directly himself. Children who answer well and are judged to have behaved are given apples, nuts, gingerbread or small sweets, generally by Nicholas's own hand; children who have not are threatened, at least in the mildest and most common surviving form of the custom, with the switch rather than struck with it, the threat itself doing the disciplinary work.
The pairing of an approving, rewarding figure with a testing, threatening one is not unique to this custom, and turns up across a wide band of European Saint Nicholas folklore under different regional names, but the German telling gives Ruprecht a specific identity, name and costume rather than leaving him as an unnamed dark companion. He carries the ashes and switch as tools of the visit rather than as weapons in any serious sense, and most twentieth and twenty-first century household versions of the custom, aimed at young children, keep him closer to a stern disciplinarian than to a genuinely frightening figure, a gentler tone than Alpine Krampus custom, further south, is generally reported to keep.