1. A descriptor repository comprising one or more computers, wherein the one or more computers are configured to perform operations for: receiving a descriptor label for a merchant, wherein the descriptor label provides contextual information for financial transactions associated with the merchant; receiving a plurality of descriptor definitions for the descriptor label, wherein each of the descriptor definitions provides contextual information for the financial transactions associated with the merchant; storing the plurality of descriptor definitions in a database; receiving one or more relevance indications for one or more of the descriptor definitions, wherein each of the relevance indications is based on a relative usefulness of a respective descriptor definition for providing contextual information for the financial transactions associated with the merchant; and associating one or more of the descriptor definitions with the descriptor label based on the one or more relevance indications.