If your repository uses composite repository item IDs, you can specify the ID with its encoded form, or in brackets as comma-delimited ID elements. For example, if an ID is composed of the string elements Massachusetts, USA, and Earth and the separator character is the default, : (colon), you can specify the ID in one of these forms:

<add-item item-descriptor="states" id="Massachusetts:USA:Earth">
    <set-property name="capital" value="Boston"/>
</add-item>

<add-item item-descriptor="states" id="[Massachusetts,USA,Earth]">
    <set-property name="capital" value="Boston"/>
</add-item>