The son of former Trinity player Richard Slater, who joined Wakefield as a 16-year-old, has impressed in the past two seasons with the club's academy sides and was named under-18s Academy Man of Steel in 2010.
And, despite interest from several Super League clubs and some Australian sides, Slater has decided to continue his future with the Wildcats.
Slater told the Wakefield Express: "Richard [Agar] had a talk to me and asked me to come down to training so I'm delighted.
"I've been playing in the reserves for a while and I'm glad I've got my opportunity.
"I just want to train as hard as I can, show Richard what I can do and make a few first team appearances, hopefully."
Coach Agar added: "I've seen things in Adam's game that have shown me he has a good foundation to work from and there's plenty to work with for him to build towards his goal of becoming a Super League player.
"He has got a terrific attitude, outstanding work ethic and with the right application he has the potential to develop well.
"He's a local lad with strong ties to the club and it's important that we ensure we develop these young players."