All players can (setting) start with the guidebook, and pouch. One explains the system, the other displays the current total number of elements a player has.
In default, the player crafts the adventure_shop via normal crafting. This can also be disabled via setting, and a server owner can decide where to place the shop(s) via creative mode.
In default, the player can also craft the adventure_guidebook, and adventure_purse.
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Without default, the player can do a command to bring up the formspec for both purse and guidebook:
/adventure_guidebook
/adventure_purse
Without default, the shop can be crafted with the /make_shop command, which requires 10 of each element to create.
Adventure core works by a player registering a node_name and element requirement, The node inventory image from the node_def/item_def is used as the picture, except for nodes with a mesh drawtype, these are displayed with a viewable mesh!