let AlertThreshold = std.contract.custom (
  fun label =>
    fun value =>
      if value >= 0.0 && value <= 1.0 then
        'Ok value
      else
        'Error {
          message = "Invalid alert_threshold '%{std.to_string value}'.\nValid range: 0.0 - 1.0"
        }
) in

{
  RoleBudget = {
    role | String,
    monthly_limit_cents | Number,
    weekly_limit_cents | Number,
    fallback_provider | String,
    alert_threshold | AlertThreshold,
  },
}