Tweaker Sample Code

Below is a sample script, written in JavaScript, to register new recipes for each vanilla recipe type through the Tweaker system, along with demoing loot table modification. It requires LibCD 2.1.0 or above. It would be placed at the location data/libcd/tweakers/tweaker_test.js.

//warning for production environments
log.info("WARNING! LibCD Tweaker sample script is running!");
log.info("If you are not in a dev environment, please report this!");

//imports - use `libcd.require`
var RecipeTweaker = libcd.require("libcd.recipe.RecipeTweaker");
var TweakerUtils = libcd.require("libcd.util.TweakerUtils");

//A shorthand to get a stick input
var stick = "minecraft:stick";
//A shorthand to get a crafting table output
var table = TweakerUtils.createItemStack("minecraft:crafting_table");

//remove the vanilla crafting table recipe, so we can use ours instead
RecipeTweaker.removeRecipe("minecraft:crafting_table");

//remove all recipes for gold nuggets - make them entirely uncraftable
RecipeTweaker.removeRecipesFor("minecraft:gold_nugget");

//remove all polished andesite slab recipes obtained by stonecutting
RecipeTweaker.removeRecipesFor("minecraft:polished_andesite_slab", "minecraft:stonecutting");

//create a recipe for a piece of tall grass and a piece of bonemeal or white dye -> a two-high piece of tall grass
RecipeTweaker.addShapeless(["minecraft:grass", RecipeTweaker.makeIngredient("fuzzy", "minecraft:bone_meal", "minecraft:white_dye")], TweakerUtils.createItemStack("minecraft:tall_grass"));

//create a recipe for a stone pickaxe and a diamond -> a diamond pickaxe with 1 durability left
RecipeTweaker.addShapeless(["minecraft:stone_pickaxe", "minecraft:diamond"], TweakerUtils.createItemStack("minecraft:diamond_pickaxe{Damage:1560}"));

//create a recipe for a stone pickaxe, a diamond, and an iron ingot -> a diamond pickaxe with 131 durability (the amount a stone pick has) left, along with an enchantment, lore and a custom name
//re-declaring is optional, but good for safety.

/*
NOTE: The current form imports code from script `libcd:import_test.js`, which contains the following JS code:
`
var TweakerUtils = libcd.require("libcd.util.TweakerUtils");
var newPickStack = TweakerUtils.createItemStack("minecraft:diamond_pickaxe");
newPickStack = TweakerUtils.setDamage(newPickStack, 1430);
newPickStack = TweakerUtils.setName(newPickStack, "Patched Pickaxe");
newPickStack = TweakerUtils.enchant(newPickStack, "minecraft:fortune", 1);
newPickStack = TweakerUtils.addLore(newPickStack, [
    "A stone pick strengthened",
    "with iron and diamond.",
    "Not very durable, but",
    "should be able to mine",
    "better than usual."
]);
`
*/
//import other test script
var imported = libcd.importScript("libcd:import_test.js");
//get the var defined in the other script to use as our output stack
RecipeTweaker.addShapeless(["minecraft:stone_pickaxe", "minecraft:diamond", "minecraft:iron_ingot"], imported.getVar("newPickStack"));

//create a recipe for a stick above a stone block with two oak planks on the right -> a crafting table
RecipeTweaker.addShaped([[stick, "minecraft:oak_planks"], ["minecraft:stone", "minecraft:oak_planks"]], table);

//create a recipe for three gravel in an upside-down L -> 1 piece of flint
RecipeTweaker.addShaped([["minecraft:gravel",   "minecraft:gravel"],
    ["minecraft:gravel", null]],
    "minecraft:flint@5");

//create a pattern/dictionary set for a shaped recipe
var pattern = [ '/ /',
                '/_/',
                '/ /'];
var dict = {
    "/": stick,
    //put a # at the front of an ID to make it a tag instead of an item
    "_": "#minecraft:wooden_slabs"
};

//create a recipe for sticks on the sides and any wooden slab in the middle -> six ladders
RecipeTweaker.addDictShaped(pattern, dict, "minecraft:ladder@6");

//create a recipe to smelt a bottle of water -> a bottle of dragon's breath
//use a getter syntax (two IDs separated by ->) for special getters like potions
RecipeTweaker.addSmelting("minecraft:potion->minecraft:water", "minecraft:dragon_breath", 200, 0.35);

//create a recipe to blast a piece of coal -> a diamond. Takes 4x the fuel and time of a standard blasting operation
RecipeTweaker.addBlasting("minecraft:coal", "minecraft:diamond", 400, 0.7);

//create a recipe to smoke a log -> a block of charcoal. Takes 4x the fuel and time of a standard smoking operation
RecipeTweaker.addSmoking("#minecraft:logs", "minecraft:coal_block", 400, 0.7);

//create a recipe to bake an apple -> a golden apple on a campfire
RecipeTweaker.addCampfire("minecraft:apple", "minecraft:golden_apple", 600, 0.7);

//get all the IDs of items in the #minecraft:logs tag
var logs = TweakerUtils.getItemsInTag("minecraft:logs");

//create recipes to convert any type of log -> any other type of log in a stonecutter, iterating over the logs tag
for (var i = 0; i < logs.length; i++) {
    RecipeTweaker.addStonecutting("#minecraft:logs", logs[i]);
}

var builder = RecipeTweaker.builder("minecraft:smelting")
    .ingredient("ingredient", "minecraft:diamond")
    .itemStack("result", "minecraft:obsidian@8")
    .property("cookingtime", 200)
    .property("experience", 0.35);

RecipeTweaker.addRecipe(builder.build());

builder = RecipeTweaker.builder("minecraft:stonecutting")
    .ingredient("ingredient", "minecraft:diamond_block")
    .itemStack("result", "minecraft:diamond@9");

RecipeTweaker.addRecipe(builder.build());

//import the stuff we need for loot tables
var LootTweaker = libcd.require("libcd.loot.LootTweaker");
var Conditions = libcd.require("libcd.loot.Conditions");
var Functions = libcd.require("libcd.loot.Functions");
var Entries = libcd.require("libcd.loot.Entries");

//start messing with loot tables!
var sheepTable = LootTweaker.getTable("minecraft:entities/sheep");
var mainPool = sheepTable.getPool(0);
mainPool.removeEntry("minecraft:item", "minecraft:mutton");
var prismarineEntry = Entries.item("minecraft:prismarine_shard")
    .addFunctions(Functions.countExact(5))
    .addConditions(Conditions.killedByPlayer());
mainPool.addEntries(prismarineEntry);