minecraft-assets/assets/minecraft/advancements/recipes/buildingBlocks/gray_wool.json

{
  "rewards": {
    "recipes": [
      "minecraft:gray_wool"
    ]
  },
  "criteria": {
    "has_white_wool": {
      "trigger": "minecraft:inventory_changed",
      "conditions": {
        "items": [
          {
            "item": "minecraft:wool",
            "data": 0
          }
        ]
      }
    },
    "has_the_recipe": {
      "trigger": "minecraft:recipe_unlocked",
      "conditions": {
        "recipe": "gray_wool"
      }
    }
  },
  "requirements": [
    [
      "has_white_wool"
    ],
    [
      "has_the_recipe"
    ]
  ]
}