Tuányuán

Privacy Policy

What this experience asks of you, and what it does with it.

What you’re asked for

To find the moon you were born under, Tuányuán asks for your date of birth, your time of birth (optional), and your place of birth, or the time zone of that place. The place is matched against a list of cities built into the page to find its coordinates and time zone, without looking anything up online, and is used only to work out the local time of your birth. The moon’s position is then calculated from that moment.

Later, the ritual invites you to write short answers to four questions. Every answer is optional.

Where the moon is calculated

The lunar calculation runs entirely in your browser, using an open-source astronomy library. Your birth details are not sent anywhere to do this.

Your written answers

At the end of the ritual, your answers are sent, together with the phase and sign already calculated for you, through this site’s server to Anthropic’s Claude API, so that a short reflection can be written from your own words. The server passes them on and doesn’t store them. Anthropic’s terms and privacy policy apply to that request.

If you leave every question blank, nothing is sent. If a reflection can’t be written, your words are simply shown back to you.

What is kept

Tuányuán doesn’t save your birth details or your answers. It doesn’t use browser storage, cookies, accounts, analytics, or advertising. Everything you enter lives only in the open page and is gone when you close or reload it.

Your mooncake

The keepsake image is drawn in your browser. “Keep this moon” saves it to your device after a confirmation. “Send this moon” opens your device’s share sheet where one is available, and where it goes from there is your choice.

Other services involved

This site is hosted on Vercel, which receives the ordinary technical information any web request includes. To display the page, your browser also fetches typefaces from Google Fonts and the astronomy library from jsDelivr. Those services receive the ordinary technical information any web request includes, such as your IP address. They don’t receive anything you enter.

Changes

If the way Tuányuán handles information changes, this page will change with it, and the Release Notes will say so.

Tuányuán

Terms of Use

A few plain understandings between you and this experience.

Using Tuányuán

Tuányuán is a personal, reflective experience made for Mid-Autumn. You’re welcome to use it for yourself and to share what it makes for you. Please use it in the spirit it was made: gently, and without trying to break, overload, or misuse it.

What you enter

You’re responsible for the information you choose to enter and for anything you choose to send to others. Please don’t enter details about other people without their permission.

What the moon can and can’t tell you

The moon’s phase and position are calculated from astronomical data and are as accurate as that data allows. The readings, reflections and meanings built around them are offered for reflection and enjoyment.

They are not scientific, medical, psychological, financial, legal, or other professional advice. Please don’t rely on Tuányuán for decisions that matter. If you’re going through something difficult, a person you trust or a qualified professional will serve you far better than any moon.

Reflections written by AI

The closing reflection is written by Claude from your own answers. It can be imperfect, and it doesn’t know your life beyond what you wrote.

Ownership

The concept, writing, visual design, and interface of Tuányuán belong to Elizabeth Xu unless otherwise stated. The astronomy library, typefaces, and the lines by Su Shi belong to their respective authors and are used under their own terms or in the public domain. Your answers remain yours.

No guarantees

Tuányuán is offered as it is. It may change, pause, or stop, and it may sometimes behave imperfectly. To the extent the law allows, Elizabeth Xu isn’t responsible for losses arising from its use.

Tuányuán

Accessibility

The ritual should be open to everyone who wants to sit with it.

Intention

Tuányuán is designed with the Web Content Accessibility Guidelines (WCAG) 2.2 at level AA as its reference. It has not been formally audited or certified, so it doesn’t claim full conformance. What follows is what has been built with care, and where it still falls short.

What’s in place

• Every button, field and choice can be reached and used with a keyboard, with a visible focus state.
• Headings, labels and landmarks give the pages a meaningful structure for screen readers.
• Form fields have visible labels, and errors are announced as they appear.
• The circle of moon phases can be moved through with the arrow keys, and it announces the phase you reach.
• Chinese text is marked as Chinese, so screen readers can pronounce it correctly.
• With “reduce motion” turned on in your system settings, the opening appears as a still scene and the other animations settle immediately.
• Everything the animations show is also said in words: your phase, your sign, your reflection and your mooncake are always written out.

Known limitations

• The opening, the lunar circle and the mooncake box are drawn visually. They are described in words around them, but the drawings themselves aren’t narrated.
• Some small supporting text, like labels and footnotes, is intentionally quiet and may fall below recommended contrast.
• City suggestions use your browser’s built-in list, which behaves differently across browsers and assistive technologies. If your city isn’t listed, you can choose its time zone instead.
• The experience hasn’t yet been tested with a full range of screen readers and devices.

Getting in touch

There isn’t a dedicated way to report an accessibility problem inside the experience yet. That will be added here when it exists.

Tuányuán

Release Notes

A quiet record of what has changed.

September 2026

Tuányuán
First Edition

Tuányuán is a lunar reflection experience built around the idea that the moon is always whole, even when we experience it in phases.

The first edition includes:

• the Mid-Autumn opening ritual, with lotus lanterns on dark water
• the circle of phases, showing one moon seen in many lights
• personal birth moon calculation, from your date, time and place of birth
• lunar phase visualization you can move through by hand
• moon sign interpretation
• four reflective questions
• the gradual illumination of your personal moon
• the full-moon reveal, with a reflection written from your own words
• the mooncake keepsake, to keep or to send

Version 1.0 · Build 2026.1