Each item in Minecraft has a unique ID assigned to it, known as an item ID, this can be used in commands to spawn the item into the game. The item ID for minecart with command block in Minecraft is shown below:
Items from earlier versions of Minecraft were assigned a numerical ID - a unique number to represent it.
The numerical ID for Minecart with Command Block is:
The Minecart with Command Block item can be spawned in Minecraft with the below command. Cheats must be enabled before this will work.
Minecarts with command blocks are, as the name would suggest, minecarts with command blocks inside. They cannot take a passenger.