These Terms of Service ("Terms") are a contract between you and Ryusuke Seto Music Lab ("Operator," "we," or "us"), an individual business based in Japan.

The Service (Tonic Clef) is offered to individual consumers worldwide from Japan. These Terms apply to all access and use unless we agree otherwise in writing.

You enter this contract electronically. By using the Service, you agree you have read and accept these Terms and our Privacy Policy.

If you do not agree to these Terms or our Privacy Policy, you must not access or use the Service.

Unless non-waivable mandatory law in your country provides otherwise, your relationship with the Operator is with a Japan-based business and these Terms govern worldwide use.

If you use the Service for an organization, you represent you have authority to bind that organization.

You must have legal capacity to enter a binding contract in your jurisdiction.

You must be at least 13 years old to use the Service. If you are under the age of majority in your country, you may use the Service only with consent and supervision of a parent or legal guardian who accepts these Terms on your behalf.

You must be at least 18 years old (or the age of majority where you live, if higher) to purchase a paid subscription.

You must not use the Service if you are located in, ordinarily resident in, or a national of a country subject to comprehensive sanctions that would prohibit us from providing the Service to you, or if you are on applicable denied-party lists.

The Service is for personal, non-commercial learning unless we authorize otherwise.

These Terms may be displayed in English and Japanese. If there is any conflict between translations, the English version controls to the maximum extent permitted by applicable law, except where Japanese law mandatorily applies to consumers in Japan.

The Service provides educational music-theory content and tools (scale/chord exploration, dictionary, sight-reading, staff paper, AI Coach, etc.) for general learning.

Free and paid tiers may be offered. Features, content, and availability may change or end at any time without prior notice. Paid subscription pricing is governed by the Paid Subscriptions and Billing section.

The Service may include beta or experimental features identified as such or reasonably understood to be evolving. They are provided as-is and may change or be removed without notice.

Some features require registration (e.g., Google or Apple). You are responsible for credential security and all activity under your account.

You must provide accurate information. We may suspend or terminate accounts that violate these Terms or pose risk to the Service or others.

Paid plans are recurring subscriptions processed by Stripe, Inc. or another processor we designate. By subscribing, you authorize charges at the displayed rate and interval until you cancel per these Terms and the checkout flow.

Prices are shown before purchase and may change for new subscriptions or re-subscriptions after cancellation. Taxes, currency conversion, and bank fees are your responsibility unless stated otherwise.

While your subscription remains active, we will not change the monthly rate applicable to that subscription (grandfathered pricing). If you cancel and subscribe again later, the price displayed at the time of re-subscription applies.

Exception: notwithstanding the grandfathered pricing above, in extraordinary circumstances beyond our reasonable control—such as natural disasters, war, significant currency fluctuation or collapse, substantial increases in taxes, payment-processor fees, or infrastructure costs, or changes in applicable law—we may revise the rate for existing subscriptions to the extent reasonably necessary. In that case, we will give reasonable advance notice by email or within the Service before the change takes effect, and you may cancel before the new rate applies. Continued use after the effective date constitutes acceptance of the revised rate.

Benefits apply only while subscription is active and the Service is available. Non-payment may cause immediate loss of paid features without refund.

Paid features are digital content supplied immediately upon payment (and account linkage if required).

TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, BY PURCHASING OR USING PAID FEATURES, YOU REQUEST IMMEDIATE PERFORMANCE, ACKNOWLEDGE THAT DIGITAL CONTENT IS MADE AVAILABLE RIGHT AWAY, AND EXPRESSLY CONSENT TO IMMEDIATE SUPPLY. YOU WAIVE ANY STATUTORY RIGHT OF WITHDRAWAL, COOLING-OFF PERIOD, OR CANCELLATION FOR CHANGE OF MIND THAT WOULD OTHERWISE APPLY TO DISTANCE CONTRACTS, EXCEPT WHERE NON-WAIVABLE LAW REQUIRES OTHERWISE.

Cancellation of a subscription stops future renewals only; it does not entitle you to a refund for the current or prior periods (see No Refunds).

TO THE MAXIMUM EXTENT PERMITTED BY LAW, FEES PAID ARE GENERALLY NON-REFUNDABLE.

We are generally unable to provide refunds, credits, or prorated adjustments for any reason, including mid-period cancellation, dissatisfaction, bugs, downtime, unused time, account deletion, or failure to use features.

After cancellation, paid access may continue until the end of the current paid period, then revert to free tier (if any). Fees for the current or prior periods are not refunded.

Chargebacks or payment disputes without contacting us via Feedback (https://tonicclef.ryusukeseto.com/feedback) first may result in suspension or termination of your account.

THE SERVICE IS PROVIDED "AS IS" AND "AS AVAILABLE." WE DO NOT GUARANTEE CONTINUOUS, UNINTERRUPTED, SECURE, OR ERROR-FREE OPERATION.

Interruption, degradation, or permanent discontinuation may occur for any reason, with or without notice, including maintenance, bugs, server failure, network issues, force majeure, or third-party outages.

TO THE MAXIMUM EXTENT PERMITTED BY LAW, THE OPERATOR IS NOT LIABLE FOR ANY LOSS OR DAMAGE FROM: (A) SERVICE INTERRUPTION OR TERMINATION; (B) SERVER OR THIRD-PARTY API OUTAGES (HOSTING, AUTH, PAYMENTS, ANALYTICS, THIRD-PARTY AI SERVICES); (C) LOSS, CORRUPTION, OR INACCESSIBILITY OF DATA INCLUDING LEARNING HISTORY; OR (D) FAILURE TO BACK UP, RESTORE, OR RETAIN DATA.

You are solely responsible for backups. We have no obligation to restore data after termination or discontinuation.

AI features (Coach, RAG-based suggestions, feedback, analysis) use third-party models.

AI OUTPUT IS FOR INFORMATIONAL AND EDUCATIONAL PURPOSES ONLY. WE MAKE NO WARRANTY AS TO ACCURACY, SAFETY, LEGALITY, OR FITNESS. WE ARE NOT LIABLE FOR ANY LOSS FROM RELIANCE ON AI OUTPUT.

Do not treat AI output as professional, medical, legal, or certified teaching advice. Use at your own risk.

All content is for general education only, not formal instruction, exams, or licensed professional advice.

You agree not to: violate law or third-party rights; access systems without authorization; scrape or reverse engineer except as permitted by law; disrupt the Service; systematically extract content to build competing products; or transmit malware or abusive material.

Violations may result in suspension or termination without refund.

Service content, software, algorithms, design, and branding are owned by the Operator or licensors. No copy, modify, distribute, or derivative works except as permitted by law or us in writing.

You retain rights in content you submit and grant us a worldwide, non-exclusive, royalty-free license to use it solely to operate and improve the Service.

You may not use, export, or re-export the Service in violation of applicable export control or sanctions laws. You represent you are not barred from receiving the Service under such laws.

TO THE MAXIMUM EXTENT PERMITTED BY LAW, THE SERVICE IS PROVIDED "AS IS" AND "AS AVAILABLE" WITHOUT WARRANTIES OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE, NON-INFRINGEMENT, AND ACCURACY.

TO THE MAXIMUM EXTENT PERMITTED BY LAW, THE OPERATOR AND ITS PERSONNEL ARE NOT LIABLE FOR ANY INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL, EXEMPLARY, OR PUNITIVE DAMAGES, OR LOSS OF PROFITS, REVENUE, DATA, OR GOODWILL, ARISING FROM USE OR INABILITY TO USE THE SERVICE, EVEN IF ADVISED OF THE POSSIBILITY.

TOTAL AGGREGATE LIABILITY FOR ALL CLAIMS SHALL NOT EXCEED THE GREATER OF (I) AMOUNTS YOU PAID IN THE TWELVE (12) MONTHS BEFORE THE CLAIM, OR (II) ¥1,000.

Where limitations are restricted by law, liability is limited to the fullest extent permitted.

TO THE MAXIMUM EXTENT PERMITTED BY LAW, ANY CLAIM ARISING OUT OF OR RELATED TO THE SERVICE OR THESE TERMS MUST BE BROUGHT WITHIN ONE (1) YEAR AFTER THE EVENT GIVING RISE TO THE CLAIM, OR IT IS PERMANENTLY BARRED.

You will indemnify and hold harmless the Operator from claims, damages, losses, and expenses (including reasonable attorneys' fees) arising from your use of the Service, your violation of these Terms, your violation of law or third-party rights, or content you submit.

Stripe, Google, Apple, hosting, analytics, AI, and font providers have their own terms. We are not responsible for their acts or omissions.

We are not liable for failure or delay due to events beyond our reasonable control, including natural disasters, war, terrorism, labor disputes, internet or utility failures, government actions, epidemics, or third-party service failures.

These Terms and all disputes (including non-contractual claims) are governed by the laws of Japan, without regard to conflict-of-law rules that would apply another country's laws.

The Utsunomiya District Court (宇都宮地方裁判所) has exclusive jurisdiction as the court of first instance. You consent to personal jurisdiction and waive venue, forum non conveniens, and similar objections.

TO THE MAXIMUM EXTENT PERMITTED BY LAW, YOU WILL NOT SUE OR PARTICIPATE IN PROCEEDINGS AGAINST THE OPERATOR IN ANY FORUM OUTSIDE JAPAN, INCLUDING EU, UK, US (INCLUDING CALIFORNIA), CANADA, AUSTRALIA, OR ELSEWHERE.

Mandatory local law applies only to the minimum extent required for a particular claim; all other claims remain under Japanese law and Utsunomiya jurisdiction.

We do not represent compliance with every local rule in every country. If you cannot agree to these Terms (including Japan dispute resolution), do not use the Service.

TO THE MAXIMUM EXTENT PERMITTED BY LAW, EACH PARTY WAIVES JURY TRIAL AND ANY RIGHT TO PARTICIPATE IN CLASS, COLLECTIVE, REPRESENTATIVE, OR PRIVATE ATTORNEY GENERAL PROCEEDINGS.

Claims must be brought only in your individual capacity.

You consent to receive communications electronically (e.g., email, in-Service notices). Legal notices to us must use Feedback (https://tonicclef.ryusukeseto.com/feedback; Google sign-in required); we may send notices to your account email or in-Service.

These Terms and the Privacy Policy are the entire agreement regarding the Service and supersede prior understandings on that subject.

You may not assign your rights without our consent. We may assign these Terms in connection with a merger, sale, or reorganization.

Our failure to enforce a provision is not a waiver. No waiver is effective unless in writing signed by us.

Nothing creates agency, partnership, joint venture, or employment between you and the Operator.

We may modify these Terms by posting updates. The "Last updated" date indicates the current version. Continued use is acceptance. If you disagree, stop using the Service and cancel subscriptions (no refund).

We may suspend or terminate access at any time, with or without cause or notice. Surviving provisions include disclaimers, liability limits, governing law, no-refund, and indemnity.

If a provision is invalid, the remainder stays in effect and the invalid part is modified minimally to be enforceable.

Questions: https://tonicclef.ryusukeseto.com/feedback (Google sign-in required; product and support inquiries).