Features

Blocks cannot be destroyed by hand, and require an item with the CanDestroy tag.

Blocks require the CanPlaceOn tag to be placed.

Interaction with mechanisms as well as trading is allowed.

Compatible in multiplayer.

Players spawn on the world spawn. Exactly on it, including the y axis even if inside buildings.

Uses and Tips for Adventure Mode

You can use it as a useful way to protect your server from griefing, since blocks cannot be broken in this mode.

Because of these breakables, you may want to keep tools out of the hands of griefers until you install a protection plugin.

Adventure Mode can be used for adventure maps, and the breakables can add an interesting feeling to the map. If you only want your players to have a tool at a certain point of time, you can connect a pressure plate with /clear @p(or @a for all players) [itemID].

Players will spawn on the world spawn exact to the block. Including the y coordinate if there is space for the player there, if not it searches upward.