Add API docs

API.md

@@ -0,0 +1,25 @@
+# Easyvend API
+Use this API if you want to make an comntainer compatible with vending and
+depositing machines.
+
+The API only has one function:
+
+## `easyvend.register_chest = function(node_name, inv_list, meta_owner)`
+Registers a node (called “chest”) for use with Easyvend. After calling this function,
+the node will be recognized as storage for vending and depositing machines.
+
+Easyvend makes the following assumptions about the chest:
+* It has an inventory
+* The inventory does not restrict the types of items you can put and take
+* The chest is owned by a player
+* The owner is specified in metadata
+
+### Parameters 
+* `node_name`: Name of the chest node
+* `inv_list`: Name of the inventory list for exchanging items
+* `meta_owner`: Identifier of the metadata variable storing the owner name
+
+### Example
+```
+easyvend.register_chest("example:superchest", "main", "owner")
+```

README.md

@@ -27,6 +27,10 @@ But it can be changed via the setting `easyvend_currency`.
 
 
 ## Appendix
+### Developer information
+If you want to a container node compatible with vending/depositing machines,
+use the Easyvend API, see the file `API.md`.
+
 ### Converting machines from `vendor` mod (experimental)
 This mod is able to automatically transform the vending and depositing
 machines from Bad\_Command\_'s Vending machines [`vendor`] mod on loading