Boyce, 24, is a former fourth-round pick of the Patriots back in 2013. He spent two years in New England before he was waived with the injury designation at the start of the 2015 season.
Boyce did catch on with another team last year and hasn’t appeared in an NFL game since the 2014 season.
Tyms, 27, originally signed on with the 49ers as an undrafted free agent out of back in 2012. He had brief stints with the Dolphins and Browns before catching on with the Patriots in July of 2014.
Tyms returned to New England on a one-year deal last year, but was waived during the preseason.
Heenan, 26, signed on with the Colts out of the CFL last year. He was waived during the preseason, but later added to their practice squad in November.
The Colts elected to bring him back on a future/reserve contract in January.
During his CFL career, Heenan has started all but three games, including 21 in 2014.