Starting Items

This script adds items on first time player joins, checking stages. GameStages mod is not required

// Listen to player login event
onEvent('player.logged_in', event => {
  // Check if player doesn't have "starting_items" stage yet
  if (!event.player.stages.has('starting_items')) {
    // Add the stage
    event.player.stages.add('starting_items')
    // Give some items to player
    event.player.give('minecraft:stone_sword')
    event.player.give(Item.of('minecraft:stone_pickaxe', "{Damage: 10}"))
    event.player.give('30x minecraft:apple')
  }
})