Trinidad is like several other of the prospect pitchers, good control but you won't see him throwing 93 mph. Im not a scout, so I don't know what pitches he throws, but I watched him in Salem earlier this season and he usually kept the pitches low, and kept the batters off balance, he didn't have a lot of strike outs, but he also stayed out of trouble for the most part. When he gave up runs it wasn't because the other team was making solid contact and hitting balls out, it was when they would put together several singles.
One thing I will note is that the Carolina League only has 8 teams so usually after a team has seen a pitcher 3 or 4 times, it is harder for the pitcher to have success. Trinidad did well while he was here, but Houston called him up quickly, so he didn't have to face some of the better hitting teams very much.