End of the stream or a document separator is expected in automation file

i am getting this error on line 1 of the code (the alias), what am i doing wrong?
regards Bas

type or paste # automatiseren van de bg verlichting dimmer
alias: bg verlichting schakelaar
description: ''
  - platform: state
    entity_id: sensor.soverom_vilde_lysbryter_action
    attribute: action
condition: []
  - choose:
      - conditions:code here