Anything more noteworthy than just dealing with fiends. If he fixed the veil, that would be noteworthy, fighting the beholders would as well. Before I joined the Council of 12, I had fought a fearsome demon and Drow, helped kill the Twisted Assassin and Black Velvet that were wanted criminals, was helping to work on the planar threats, dealing with fiendish orcs roaming the Stonelands, trying to take down the Lady of the Bells, as well as all kinds of minor threats around the realm like goblins, orcs, undead, kobolds, gnolls, giants, etc. Most of those I'd say are notable acts that proved I was willing to protect the realm. It wasn't me just spouting my mouth off.
Now Robert may be Councilor material, but until he has a few noteworthy accomplishments under his belt, it's really just good intentions. Certain factions are guaranteed a seat, like Ravens, Precept, Wildwalkers, and House of Morning. Seats of Merit are earned and it is meant to be a difficult task. We should certainly keep an eye on him, possibly help him accomplish the things he seeks to. I'm not saying he can't join the Council for the record, I'm just saying he can't join yet.