Currently under testing, "The Foundry for Star Trek Online (Beta) Mission Authoring Tool" will allow users to customize pre-made planets with their own encounters, objects, and stories. They'll be able to customize pre-made star systems or create their own from scratch, too.
Players will also be able to create missions that take place in existing open world areas and browse through user-made stories and access content created with The Foundry through a "Community Authored" section of the game.
Looking to ensure a certain level of quality for this custom content, Cryptic will invite Star Trek Online players to sign up as reviewers to examine and veto the missions before the general public can access them. Normal users will also be able to rate episodes they've completed.
Launched in February, Star Trek Online received mixed reviews as critics cited issues with bugs, a lack of polish, and repetitive missions. Cryptic has worked to resolve those issues by releasing "seasons" (major updates), and appears to be addressing that last complaint with The Foundry.
The developer's City of Heroes team, which joined NCsoft as Paragon Studios several years ago, released a similar tool called the Mission Architect for the superhero MMORPG in April 2009.