@kerlyn-bsd3 great! Can you give a concrete example (or do you simply mean continuing to use list as opposed to view or something?). In that case, I'd actually prefer another name, I think something like view is actually a bit more descriptive in this case, as you'd like to "view" the source.
I mean using command names and syntax exactly as they are used in gbd (when there's an equivalent command, e.g. 'break'). I need to go through the gdb commands again, but many take a 'linespec' to identify location (see section 9.2 of the gdb manual, http://www.gnu.org/software/gdb/documentation/).
I think there are two benefits: 1) it may make IDE support easier, 2) there will be significant regularity across the RPC interface.
Note: this is not far off from how 'break' currently works.
I'll submit a PR for 'list' and you can see how you like it.