Recipes and tags don't work

// one of my recipes
{
  "type": "minecraft:crafting_shaped",
  "pattern": [
    "ccc",
    "crc",
    "ccc"
  ],
  "key": {
    "c": {
      "tag": "minecraft:carpets/ruby_carpet"
    },
    "r": {
      "tag": "forge:gems/ruby"
    }
  },
  "result": {
    "item": "ruby:ruby_carpet",
    "count": 8
  }
}

//a tag from vanilla I add an item to
{
  "replace": false,
  "values": [
    "ruby:ruby_carpet"
  ]
}

//a tag from forge I add an item to
{
  "replace": false,
  "values": [
    "ruby:ruby"
  ]
}