Add a function that reads a sites selection from the model runs table?

This might be a useful helper if your scenario or scheme has a default list of sites that are included.

The function would return a character vector of site codes, that you could store as a local variable, and then pass to the sites argument of the various reskit compile functions.
If no sites are specified in the table (or ALL) then this function would return NULL, which is then treated by reskit as "no filter".

It would potentially base its lookup on a selection of variables to filter the model runs table on, or it could just require a single argument, the specific row ID (there's already a helper function in azkit that should retrieve a single row from the table, though this might need some adaptation to ensure it is user-friendly enough).

Just an idea for now - would this be useful?

Start by reviewing the existing azkit helper for retrieving a single model-runs row and the reskit compile functions that accept a sites argument. Clarify whether selection uses a row ID or multiple filter variables, then define the behavior for missing sites and ALL. Done means the helper returns site codes or NULL and its interface is settled for use with the compile functions.