Hawkins, 25, worked out with the Chiefs during their three-day minicamp this week. The former University of Texas standout went undrafted in 2014 but has spent time with the Eagles, Browns, Cowboys, Dolphins, 49ers, Panthers and Jets during his NFL career.
Hartfield, 25, went undrafted out of Southwestern Oklahoma State in 2016 after 73 tackles, 25 pass breakups and five interceptions his senior season. He has spent time with the Cardinals and Titans.
The Chiefs signed Brooks as an undrafted rookie last month out of the University of Texas of the Permian Basin, while Jean-Baptiste was a second-round pick of the Saints in 2014.