The Seattle Seahawks added some tight end depth on Friday, agreeing to terms on a one-year deal with Luke Willson, a league source told ESPN's Adam Caplan.

A fifth-round pick in 2013, Willson appeared in 56 games with the Seahawks during his first four seasons in the league.

Terms: One year, up to $3 million

ESPN 150 ranking: No. 115

Grade -- C: Willson will return and compete for the No. 2 tight end job behind Jimmy Graham. He is a tough, reliable player who is well-liked by his teammates and knows the Seahawks' offense. The move is somewhat surprising, though, given that Seattle used a third-round pick on Nick Vannett last year and the 2017 draft class is loaded with tight end talent. Willson saw a career-low 21 targets last season and caught 15 passes for 129 yards. Something to keep in mind going forward is that the Seahawks may look to use more two-TE sets in 2017. Last season, out of personnel groupings that had two tight ends, Russell Wilson completed 73.7 percent of his passes (third), averaged 10.27 YPA (third) and posted a QBR of 88.7 (second).

What it means: The Seahawks still could use a high draft pick on a tight end. They have five selections in the first three rounds, and only one of their current tight ends (Vannett) is under contract past the 2017 season. The Willson signing also could mean that the Seahawks were unimpressed with Vannett during his rookie season. Pete Carroll talked up Vannett at the combine, but if the Seahawks were confident enough in his ability to assume the No. 2 tight end role, they likely would not have brought Willson back.

What's the risk? This appears to be a low-risk signing. It's unclear at this time how much of Willson's salary is guaranteed and how much is tied to bonuses and incentives. If Graham suffers an injury, the Seahawks now have a tight end they can rely on to be in the right place and execute his job. Should Vannett or a rookie tight end impress and win the backup tight end job, great. But if not, Seattle knows what it has in Willson.