Forge and Theater for Halo: Reach will be available for Xbox One at launch but will come later for PC, 343 has confirmed.
Explaining the decision in a post on Halo Waypoint, Michael Fahrny, lead producer on Master Chief Collection PC, said making Forge a "true PC first experience" would be a lot of work.
"When you look specifically at Forge and what it truly is, it is a 3D editing tool that was built completely for console," Fahrny said.