minecraft-assets/data/minecraft/loot_tables/blocks/tall_seagrass.json

{
  "type": "minecraft:block",
  "pools": [
    {
      "rolls": 1,
      "entries": [
        {
          "type": "minecraft:item",
          "name": "minecraft:air"
        }
      ],
      "conditions": [
        {
          "condition": "minecraft:match_tool",
          "predicate": {
            "item": "minecraft:shears"
          }
        }
      ]
    }
  ]
}