A mission (quest) is represented by an object in the missions holder (system_missions). These can be made with "make quest". You need to give a quest name and a quest zone. It will be then created for you, in the form quest_%s where %s is the name. For example, quest_hangar.

Unlike the traditional dirt system, missions usually need to be accepted before they are attempted.

"mname" (yes, mname) is the actual user visible name of the mission eg Bandits or Invincible.

"questpoints" is the number of points the quest actually gives you.

The Private flag makes it invisible to mortals and not acceptable - intended for missions in development and not ready to be deployed.

rank.min can be set to a value to indicate the minimum rank you need to be to attempt the mission.

The zone's "quest" property should be set to the quest id to make sure that when it resets that Smith knows which mission it was associated with. Also this will stop Commanders and others from displacing into a zone associated with a quest they haven't done yet.

You can make one mission have a prerequisite of another mission by setting the "prerequisite.x" array property on it to the id of the other mission. (for example quest_12 silo has "prerequisite.0" = quest_9. Don't forget to update "prerequisite.count" appropriately!

For missions like Bandits and Silo which share the same zone, it should be impossible to have both out at the same time (ie they are mutually exclusive). This is accomplished via the "mutex" which on both missions is set to the other mission. Three(and higher)-way mutexing isn't supported but would be easy to add so just file a bug report if you need.

Some missions like Academy can't be accepted instead when you try to accept them it tells you to just go and to it. To do this set the Simulation flag in the mission object. (Obviously though the Academy mission can not usually be accepted anyway, as you have to get to a certain rank before you can use the missions board - this is subject to change, though.).

Finally, you can now set the "nation" property on a mission to specify what nation the mission is associated with. (the default is "british:mod"). Missions will only be shown on missions board with the same or more specific nation property. See the missions board docs for details.