minecraft-assets/data/minecraft/recipes/brush.json

{
  "type": "minecraft:crafting_shaped",
  "category": "equipment",
  "key": {
    "#": {
      "item": "minecraft:copper_ingot"
    },
    "I": {
      "item": "minecraft:stick"
    },
    "X": {
      "item": "minecraft:feather"
    }
  },
  "pattern": [
    "X",
    "#",
    "I"
  ],
  "result": {
    "item": "minecraft:brush"
  }
}