-- The first argument of the function below is the ID of a mission type, it must be unique!
local obj = MISSIONS.NewMissionType("example")

    -- Disable the mission type
    -- As the addon is most likely loaded after all other addons,
    -- you can check for specific a specific condition.
    -- (Example: Does my global addon table exist?)
    obj:SetDisabled(true)

    -- Set the Imgur ID of the image which will be downloaded by clients and be used.
    --At the moment, other image platforms are not supported.
    -- Images are loaded using a proxy so even players from Turkey should be able to see them.
    obj:SetImgurIconID("nJU8Mrd")

    -- This is the string that will be displayed.
    -- ":value:" will be replaced with the current (formatted!) progress.
    obj:SetDescription("This is an example mission which requires :value: amount of something")

    -- obj:AddTier(progressRequired, rewardOverride)
    -- Those must be kept in order!
    obj:AddTier(10, 1000)
    obj:AddTier(20, 5000)
    obj:AddTier(30, 10000)

    -- Save the progress instantly after it changes?
    obj:SetSaveOnChange(true)

    -- Instantly network progress changes to the player?
    obj:SetNetworkOnChange(true)

    -- This function allows to modify the displayed value of a mission type.
    obj:SetFormatFunction(function(value)
        return value .. " points"
    end)

    -- This function allows you to check if a player is eligible to get this specific mission assigned.
    -- Return false to exclude it from a player's possible mission pool.
    obj:SetEligibleFunction(function(p)
        return false
    end)

    -- obj:AddHook(hookName, function(self, ...))
    -- "self" is the mission object, it will always be added as first argument
    obj:AddHook("EntityTakeDamage", function(self, target, damageInfo)
        -- example code
        local mission = target:Missions():Get(self)
        if (mission) then
            mission:AddProgress(1)
        end
    end)

    -- obj:AddTimer(timerID, delay, repetitions) Check out https://wiki.facepunch.com/gmod/timer.Create
    -- The first function argument will be the mission object
    obj:AddTimer("SomeTimerID", 1, 0, function(self)
        -- your code here
    end)

-- Don't forget to register the mission at the end.
obj:Register()