Features

A feature is a concept introduced by Liquip. It provides support for modifying items in other ways than just enchantments.

Features may or may not be tagged.

Untagged features have a value of null or true.

Tagged features have a value of anything but null.

Features are stored in an object called features like this one:

{
  // ...
  "features": {}
}

For example, to make your item unbreakable you'd have to write this:

{
  // ...
  "features": {
    "minecraft:unbreakable": true
  }
}

You could also use null inplace of true as the minecraft:unbreakable feature is untagged.

An example of a tagged feature would be this:

{
  // ...
  "features": {
    "minecraft:dye_leather": "#00FFC0"
  }
}

This would make your item - if it was made of leather - colored this specific color.