Both Vandoorne and Magnussen will have a formal role with the F1 team.
McLaren has confirmed that Stoffel Vandoorne will have a formal role with the team in addition to tackling the GP2 championship for the second time.
The Belgian won four GP2 races in his rookie year with ART and drove the McLaren-Honda test car in Abu Dhabi, although it barely ran.
Difference in Stoffel and Kevin's roles
“Stoffel is McLaren-Honda's Test & Development Driver. Kevin is McLaren-Honda's Test, Reserve & Third Driver,” said a team spokesman. “Both of them were present at today's McLaren-Honda press conference and both of them are and will continue to be integral members of the McLaren-Honda family.
“In addition, Stoffel's prime aim next season will be to win the GP2 Championship, which objective we at McLaren-Honda will be doing our utmost to assist.”