polkit(8) manpage for the object structure and available API.
If you don't know the action name, run
pkaction | grep cups
The possible results are
NO. Returning a result is final. Returning
nullwill continue checking other rules.
Put your rules in
/etc/polkit-1/rules.d/*.rules. (You can check everything in one giant addRule, or you can have a separate file and separate addRule for each program; it doesn't matter.)
To test your rules, use
pkcheck -u -p $$ -a org.freedesktop.packagekit.upgrade-system