Additional fields - how to do object? (Mongo)

 emailNotifications: {
        type: "?????",
        required: false,
        input: true,
        validator: {
          input: z.object({
            bountyLive: z.boolean(),
            submissionReceived: z.boolean(),
            submissionReviewed: z.boolean(),
            manageReviewers: z.boolean()
          }),
          output: z.object({
            bountyLive: z.boolean(),
            submissionReceived: z.boolean(),
            submissionReviewed: z.boolean(),
            manageReviewers: z.boolean()
          }),
        },
      },