The Republic of Ireland Under-21 midfielder has been snapped up by the Tigers on a short-term deal after a successful trial, following his release by Arsenal at the end of last season.
Henderson came off the bench to play the last 15 minutes of Tuesday night's 1-0 Capital One Cup victory over Huddersfield at the KC Stadium.
"Conor has signed a deal because we've liked what we've seen in him," Bruce told the Hull Daily Mail.
"We think he's someone that's going to be a late starter. He's had two serious knee injuries and already missed the best part of two years in his career.
"He's got a lovely left foot and likes to get the ball down and play, just as you'd expect from someone who's come through the system at Arsenal. It will be a good experience for him."
The only goal of a dour third-round encounter came in the 59th minute when George Boyd crossed in for German striker Nick Proschwitz to score from eight yards out.
Proschwitz cost Hull £2.6million when he signed from SC Paderborn last summer, but he was making only his 11th start for the club on Tuesday havign failed to hold down a first-team place.
However, Bruce has encouraged the 26-year-old to keep plugging away and be ready for his Premier League chance when it comes.
"The one thing the kid can do is score a goal. When the opportunity arises, you expect him to score," said Bruce.
"That part of the game is so easy for him. It's the other part (his physical game) that has to improve. We'll work on that. Certainly he's better than he was 12 months ago but he still has to adapt.
"He's part of a 25-man squad. I wanted him to go out somewhere but he didn't go. The more he plays and the more he scores, then good for him."