Hand converted with online PokerStrategy.com hand converter:
$0.5/$1 Fixed-Limit Hold'em (5 handed)
Preflop: Hero is BB with 3:c, A:c.
3 folds, SB raises, Hero 3-Bets, SB calls.
Flop: (6 SB) A:d, T:d, 9:d (2 players)
SB checks, Hero bets, SB raises, Hero calls.
Turn: (5 BB) 2:c (2 players)
SB bets, Hero calls.
River: (7 BB) Q:d (2 players)
SB bets, Hero folds, SB gets uncalled bet back.
Final Pot: 7 BB.
Against a showdown bound TAG. I think 3-betting the flop is best... Fold river?
No yo are in position so you don't have to 3-bet here. I like a calldown as you get the most from a semibluff and lose the less against a better hand.
The river is close but as a lot draw come in I think a fold is a good option here.
Do you think we have enough equity here? Sure he won't 3-bet any better hand but I really don't like calling down against a 3-bet. As you are in position you don't have to fear giving away a freecard. I don't mind staying here passive.
If you want you can try giving him a range and equilate it. Else I do this later. 
