nEngine/examples/sample-game/content/statemachines/chicken-egg.yaml

# Production rule (D9 / D19): the engine emits animal-produce per eligible day
# for a mature chicken; this machine turns that event into an egg grant. The
# machine alternates on successive animal-produce events, so the egg is granted
# on every second produce — frequency is language-owned, not engine-owned.
id: chicken-egg
initial: waiting
states:
  - id: waiting
  - id: laid
    onEnter:
      - action: give-item
        itemId: egg
        qty: 1
      - action: play-sound
        sound: coin
transitions:
  - from: waiting
    to: laid
    on: animal-produce
    when:
      op: eq
      path: payload.animalDefId
      value: chicken
  - from: laid
    to: waiting
    on: animal-produce
    when:
      op: eq
      path: payload.animalDefId
      value: chicken