Matrix Version: 18.104.22.168
I’ve found that %asset_parent% for a site asset will return the asset itself, while %asset_parents% will return the id of the parent - not sure if that is expected behaviour or not?
I’m not entirely sure how to read the keyword explanation on - https://matrix.squiz.net/manuals/concepts/appendices/keyword-replacements
: Returns the current parent asset based on the current asset in its lineage context.
This may of course be a bug fixed in 5.5 (as per discussion on Keyword for site details for current listed asset?)