Agent Checkers

Have your agent build a checker board.

A checker board of blocks

Try the code:

player.onChat("checkers", function () {
    agent.setItem(QUARTZ_SLAB, 50, 1)
    agent.setItem(NETHER_BRICK_SLAB, 50, 2)
    agent.teleportToPlayer()
    agent.move(FORWARD, 1)
    for (let i = 0; i < 10; i++) {
        for (let j = 0; j < 5; j++) {
            agent.move(FORWARD, 1)
            agent.setSlot(1)
            agent.place(BACK)
            agent.move(FORWARD, 1)
            agent.setSlot(2)
            agent.place(BACK)
        }
        if (i % 2 == 0)
            agent.turn(LEFT_TURN)
        else
            agent.turn(RIGHT_TURN)
        agent.move(FORWARD, 1)
        if (i % 2 == 0)
            agent.turn(LEFT_TURN)
        else
            agent.turn(RIGHT_TURN)
        agent.move(FORWARD, 1)
    }
})