tcc/servers/bedrock/behavior_packs/vanilla/spawn_rules/guardian.json

{
  "format_version": "1.8.0",
  "minecraft:spawn_rules": {
    "description": {
      "identifier": "minecraft:guardian",
      "population_control": "monster"
    },
    "conditions": [
      {
        "minecraft:spawns_underwater": {}
      }
    ]
  }
}