This was a depth trade for both teams. The Jets were looking for a No. 3 safety after losing Doug Middleton recently to a torn pectoral muscle. They also could be without backup Rontez Miles, who suffered an eye laceration last week and is out indefinitely.
Brooks, drafted 79th overall by the Baltimore Ravens in 2014, has appeared in 34 games with no starts. The Eagles claimed him on waivers last September; he played in 11 games, with one interception and four forced fumbles.
A physical presence who plays with an edge, Brooks had a strong start to offseason training and appeared to be in good position to make the roster. The Eagles' recent acquisition of ex-Bills player Corey Graham, however, made for a crowded safety picture that includes Malcolm Jenkins, Rodney McLeod and special-teams ace Chris Maragos.
McDougle was having his best training camp with the Jets, who drafted him 80th overall, but he was on the roster bubble. His career has been hampered by injuries. He missed his rookie year due to major knee surgery and has played in only 20 games, primarily on special teams.
The Eagles have been aggressive in their pursuit to upgrade at cornerback. They recently sent receiver Jordan Matthews and a third-round pick to Buffalo for Ronald Darby, but they clearly felt additional talent was needed while they wait for rookie Sidney Jones to recover from an Achilles rupture.
Jalen Mills, who was a seventh-round pick in 2016, is projected to start opposite Darby on the outside.
ESPN's Tim McManus contributed to this report.