How do I get spells to use custom resources with Ammunition API and Roll20 5e sheet

I have scrolls of fireball and a staff of the woodlands.  In the campaign, there will be lots more items that can cast spells.  How can I drag spells into the character sheets from the compendium, but have them use a custom resource? Right now I just remake all of the spells in the “Attacks & Spellcasting” section.  But it would look a lot nicer if I could just use the compendium spells that have the nice “Show Description” button in the text log. Edit:  I am using the “5th Edition OGL by Roll20 Companion”.  I am able to get ammo to work and currently have a few items auto use ammo when I click them.

Having a quick scan through The Aaron's Ammo script ( <a href="https://github.com/Roll20/roll20-api-scripts/blob/master/Ammo/Ammo.js" rel="nofollow">https://github.com/Roll20/roll20-api-scripts/blob/master/Ammo/Ammo.js</a> , also available directly from the API dropdown) indicates this -should- be able to handle what you want, although you'd likely have to create a macro to call the Ammo API as well as cast the fireball. Quoting from the API help text: Ammo provides inventory management for ammunition stored in a character attribute. If the adjustment would change the attribute to be below 0 or above it's maximum value, a warning will be issued and the attribute will not be changed. There are quite a few examples in the API helptext, so I suggest taking a look and having a play with that.