Privacy

Suikō is a journal. What you write in it is yours, it’s private, and this page says exactly what happens to it.

What we keep

• Your account. The email address you sign in with and a password, stored hashed. If you subscribe, a customer id from the payment provider.
• Your pages. Every entry, every draft as you save it, and every version you send for a read. A version that has been read is kept exactly as you wrote it, so the marks on it always point at real text.
• The marks. Everything the editor says about a page, and what you did with each mark: done, wrong, helpful, and any note you wrote about one.
• Settings. Language, timezone, approximate Japanese level, writing direction, page length, and the way marks are drawn.
• Notes you send us. Anything you write in the feedback box, with the page you were on, your plan, your language, and your browser’s name so we can reproduce what you saw.
• Usage of the editor. For each read: which model answered, how long it took, how many tokens it used and what it cost. Not the text.

Where your writing goes

When you ask for a read, the text of that page is sent to the company whose model does the reading. Today that is Anthropic (the editorial read, the alternative version, and the daily prompt) and Google (the proofreading reads). They see the page, the prompt it answers, and the marks from earlier reads of the same page. They don’t see your email address or who you are. They also receive the approximate level you chose, so the read can adjust its depth and explanations.

Nothing is sent until you press the button. Writing, saving, and finishing a page without a read sends nothing anywhere.

What each company keeps of what it’s sent is set by its own terms for API customers, which are linked from the support page. We don’t use your writing to train anything, and we don’t sell it or share it with anyone else.

Who else handles it

• Supabase stores the account and the database.
• Vercel runs the site. Like any web host it keeps request logs with your IP address and browser for a short time. Our own logs record errors and a few words of a page when a mark is dropped for repeating one you’d already closed.
• Stripe handles subscriptions bought on the web. Your card never reaches us.
• Apple handles subscriptions bought in the iOS app.

How the app is used

We record how the app is used (which screens you open, how long they stay open, choices like closing the purchase sheet, and errors) on our own servers, to see where Suikō is hard to use. It never includes anything you write, and it’s never shared with anyone. A cookie in your browser tells one visit from the next; clearing it starts over. There’s no advertising and no tracking across other apps or sites.

In the EU, the EEA, the UK and Switzerland we ask before recording anything. Wherever you are, you can turn it off here. What was recorded while you were signed in is deleted with your account.

Deleting your account

Settings has a button for it. Deleting your account removes your pages, every version of them, every mark, your settings and your notes to us, immediately and for good. We keep one line saying an account was deleted, with its sign-up date, plan and how many pages it had, never who it was or anything it wrote, so we can see why people leave. There’s no grace period and no copy we can bring back, so export anything you want to keep first. If you have a subscription, cancel it before you delete, so nothing is billed to an account that no longer exists.

Your rights

You can read everything we hold about you inside the app, change your address and password in Settings, and delete all of it as above. To ask for a copy of your data in a file, or for anything this page doesn’t answer, write to us at the address on the support page.

Changes

If this page changes in a way that matters, the date at the top moves and we say what changed on the support page.