Most identifiers are conveniently named <name>, making it easy to find them by simply scanning for "name" elements. However, not all identifier elements are so conveniently named.
For example, other identifier elements include: <from-zone-name>, <to-zone-name>,<neighbor-id>, <transit-area>, and so on, and any configuration change made within one of these hierarchies, which have non-"name" identifiers, must include the identifiers in order to be valid. However, the problem is that there is no indication given within the configuration XML itself whether a particular element is an identifier or not.
A formal mechanism has been requested that informs scripts whether an element is an identifier or not. In the meantime, you can find a workaround on this page: Identifying Configuration Identifiers.