Bug 24865 made it possible to use a notice to replace the default wording of the description for overdue fines. It would be helpful to expand that functionality to all debit types, both system-defined and local. It might make more sense to put this within the Debit Type setup than to continue using notices, though. These custom descriptions would allow Template Toolkit as notices do, however, for formatting, logic, and value transformation -- for example, one library wants the description to tell what portion of the fee goes to local tax.
Weird clarifying note here: this suggestion is to allow customization of what goes into the accountlines.description field when a debit is recorded in the patron's account. This suggestion is *not* to change the value in account_debit_types.description, which is the display value used when selecting a debit type to be used when creating a debit on a patron's account.