Terms of service

Last updated 11 October 2026

These terms are an agreement between you and Yehuda Ringler ("we", "us") for using Tangent at https://sandbox.tangentailearning.com. By signing in you accept them and our privacy policy. If you don't agree, don't use Tangent.

1. Who may use Tangent

You must be at least 13. If you are under 18 (or the age of majority where you live), a parent or guardian must agree to these terms for you, and only an adult may buy credit or a plan. You may not use Tangent where the law forbids it.

2. Your account

You sign in with an email address you control, Google, GitHub or a passkey. You are responsible for what happens under your account; tell us at privacy@tangentailearning.com if you think someone else has access to it. You can delete your account at any time from the account menu.

3. AI-generated content

Replies in Tangent are written by AI models, not people. They can be wrong, incomplete, out of date or biased, even when they sound confident. Don't rely on them for medical, legal, financial, safety or other important decisions without checking with a qualified person. You are responsible for how you use what Tangent produces.

4. Your content

You keep all rights to what you write, and, as far as we're concerned, to the replies generated for you. You give us the permission we need to run the service: to store your content and send it to the AI provider that writes the reply. When you publish a share link, you also give us a worldwide, non-exclusive, royalty-free license to host, copy and display that conversation to anyone who has the link. These permissions end when you delete the content or revoke the link, except for copies already shared or cached, and copies we must keep as evidence, as the privacy policy describes.

You are responsible for your content and for any share link you publish. Only share what you have the right to share. Share links are available only to accounts we enable them for. Anyone can export a conversation and share the file; where you put it is up to you, and so is the responsibility for it.

Anyone who opens a shared conversation can report it. We may take it down while we review a report, and remove it if it breaks these terms or the law. A shared page says that its replies are AI-generated and that a user, not Tangent, shared it.

5. Acceptable use

Don't use Tangent to:

• break the law, or create or share content that infringes anyone's rights, including copyright and privacy;
• create or share sexual content involving minors, content that harasses or threatens people, or incites violence against them, or malware;
• plan or prepare violence against anyone;
• post other people's personal information, such as their home address, phone number or identity documents, without their permission (doxxing);
• break the usage policies of the AI provider handling your request (for example OpenRouter's and the model maker's);
• get around rate limits, billing or security, the screening of share links or the limits on them (for example with more accounts or by rewording what was refused), probe other users' data, or overload the service;
• resell access, or use automated means to scrape or bulk-generate content outside the app.

We may remove content, turn off sharing for an account or suspend accounts that break these rules, and report illegal content to the authorities.

6. Your own API keys

If you add your own AI provider key, your use of that provider is between you and them: their terms apply and they bill you directly. We don't charge for replies on your own key.

7. Membership and paid credit

• Credit and the membership are sold through Polar Software, Inc., our reseller and merchant of record: you buy from Polar, which processes the payment, calculates and collects tax, issues invoices and receipts, and handles refunds and disputes. Polar's terms for buyers also apply to your purchase.
• Prices for paid replies are the AI provider's cost (including its credit-purchase fee) plus a markup shown in the app. Polar's processing fee comes out of each purchase, and tax is added at checkout.
• Credit is prepaid and is used up as you send messages. It has no cash value and can't be transferred, to another account or to the open pool. It doesn't expire while your account exists. Deleting your account forfeits any credit left.
• Where the service requires a membership to generate replies, it renews automatically each year until you cancel it under "Manage billing". Cancelling stops future renewals; the membership runs to the end of the paid year, and credit you bought stays usable. The membership includes no credit.
• Credit and the membership are not refundable, except where the law requires it or under Polar's terms for buyers: as merchant of record, Polar may refund a purchase (for example, to prevent a chargeback). Refunded credit is removed from your balance. If you're a consumer in the EU or UK, you agree that credit is delivered right away and acknowledge that, once you start using it, you lose the 14-day right of withdrawal for the part used.
• The open pool is free credit we provide, at our discretion, that any signed-in learner may use within its limits. We fund it ourselves; pool credit isn't for sale. Replies from the pool cost you nothing. We may change the pool's funding, model, limits and availability, or end it, and it may be empty.
• We may change prices; changes apply to credit bought or membership periods starting after the change.

8. Copyright complaints

If you believe content shared through Tangent infringes your copyright, send a notice to privacy@tangentailearning.com with: your contact details, the work you claim is infringed, the share link, a statement that you believe in good faith the use isn't authorized, and a statement under penalty of perjury that your notice is accurate and that you are the owner or authorized to act for them, with your physical or electronic signature. You can also report the link from the shared page; a link reported for copyright is taken down while we review it.

We remove infringing content, and we act against repeat infringers: once we have removed 2 of your share links after reports, sharing is turned off for your account, and we may close the accounts of repeat infringers.

9. Our rights

Tangent's source code is open source under the MIT License, which governs your use of the code itself. The hosted service, its design, and the name and logo belong to Yehuda Ringler. "Tangent" and the Tangent logo are our trademarks; neither these terms nor the MIT License give you any right to use them, so a copy you run yourself must use a different name and logo.

10. Changes and availability

We may change, suspend or stop all or part of Tangent. We'll give reasonable notice of significant changes to these terms (in the app or by email); continuing to use Tangent after they take effect means you accept them. If we shut Tangent down we will give you time to export your conversations.

11. Ending the agreement

You can stop at any time and delete your account. We may suspend or close your account, or turn off sharing for it, if you break these terms or if the law requires it. We will tell you why, unless the law forbids it or telling you could harm an investigation, ours or the authorities'.

12. Disclaimers

Tangent is provided "as is" and "as available". To the extent the law allows, we disclaim all warranties, express or implied, including fitness for a particular purpose, accuracy and uninterrupted availability.

13. Limitation of liability

To the extent the law allows, we aren't liable for indirect, incidental, special, consequential or punitive damages, or for lost data, profits or goodwill, and our total liability for any claim is limited to the greater of what you paid us in the 12 months before the claim and US$50. Nothing in these terms limits liability that can't be limited by law, or your rights as a consumer under mandatory law where you live.

14. Indemnity

If someone makes a claim against us because of your content or your breach of these terms, you agree to cover our reasonable costs of it, to the extent the law allows.

15. Governing law

These terms are governed by the laws of the Commonwealth of Pennsylvania, USA, and its courts have jurisdiction, except where mandatory consumer law where you live says otherwise.

16. Contact

Yehuda Ringler: privacy@tangentailearning.com