Here’s how to update a checkbox value in a Notion database using the Notion API.

Each entry is considered to be a page.

So once you have that entry, let’s assume it to be the variable named page, you’ll have its id under page.id

I’ll also assume you have the Notion client initialized.

import { Client } from '@notionhq/client'

//...

const notion = new Client({ auth: process.env.NOTION_API_KEY })

Then you can do this to set value of the checkbox named “Ready” to true:

await notion.pages.update({
  page_id: page.id,
  properties: {
    Ready: {
      checkbox: true,
    },
  },
})