When a hand is obvious that certain number of tricks can be taken, it can be claimed to do so. For example, after drawing trumps, if the declarer has only trumps left, he/she can claim all remaining tricks.
Technical details Edit
Laws 68 to 70 is about claims and concessions. Law 68 states that, "Any statement to the effect that a contestant will win a specific number of tricks is a claim of those tricks. A contestant also claims when he suggests that play be curtailed, or when he shows his cards." A claim has to be clarified, by stating how to get those tricks.
When a claim is agreed Edit
Law 69 specifies that, when the claim is not objected and the next board is called to play or the round ends, it is agreed and scored. However, it may be withdrawn by the director within the correction period.
When a claim is objected Edit
The director must be called in any doubt, and no action may be taken before. Then, the director rules the deal according to law 70.