From his representatives:
Harrison backed up Wesley Johnson last year but couldn't crack the starting line-up despite the fact Johnson graded out as the worst center in the NFL according to Pro Football Focus.
After playing just five snaps in the first 14 games, he finally got a chance to start with two weeks to go when Johnson was injured and although he made highlight reels by getting out in front of Bilal Powell on a long touchdown run, he ended up grading out even worse than Johnson usually did. However, he saw plenty of action the following week too and fared a little better.
Harrison will probably get a minimum level deal that doesn't guarantee him a roster spot. However, the Jets would be wise to retain a player with starting experience because new starter Spencer Long has had some durability issues. Harrison has made 24 NFL starts, 20 of which were at center.
Bonus Link: Scouting report on Harrison