Terms of Service

Last updated: March 27, 2026

Welcome to RinKuzu. These Terms of Service (“Terms”) govern your access to and use of the RinKuzu platform operated by Hanoi University of Science and Technology (“we,” “us,” or “our”) at https://www.rinkuzu.app(the “Platform”). By accessing or using RinKuzu, you (“you” or “User”) agree to be bound by these Terms. If you do not agree to these Terms, do not access or use the Platform.

1. Acceptance of Terms

By creating an account, logging in, or otherwise using any feature of RinKuzu, you confirm that you: (a) are at least 13 years of age, or have the express consent of a parent or guardian if under 18; (b) have the legal capacity to enter into a binding agreement; and (c) are not barred from using the Platform under applicable law. If you are accepting these Terms on behalf of an organization, you represent that you have authority to bind that organization to these Terms.

2. Account Registration and Security

2.1 Account Creation

You must provide accurate, complete, and current information during registration. You may not register under a false identity or on behalf of someone else without proper authorization. Accounts are non-transferable.

2.2 Account Security

You are solely responsible for maintaining the confidentiality of your login credentials (email and password) and for all activities that occur under your account.

You must notify us immediately at support@rinkuzu.app if you become aware of any unauthorized use of your account. We are not liable for any loss or damage arising from unauthorized use of your credentials.

2.3 Account Termination

We reserve the right to suspend or terminate your account at our sole discretion if you violate these Terms, engage in prohibited conduct, or pose a security risk to the Platform or its users. We will provide reasonable notice where practicable unless immediate termination is required for legal compliance or security reasons.

3. Description of Service

RinKuzu is an AI-powered adaptive learning platform that transforms PDF documents into personalized quiz-based learning experiences using knowledge graphs and Bloom's Taxonomy. Core features include:

  • PDF-to-quiz generation using Google Gemini AI
  • Adaptive learning sessions with SAINT-Bloom knowledge tracing
  • Curriculum sequencing using Dueling DQN reinforcement learning
  • Knowledge graph visualization of prerequisite concepts
  • Mastery tracking across six Bloom's Taxonomy cognitive levels
  • Community quiz sharing and browsing

We reserve the right to modify, suspend, or discontinue any feature of RinKuzu at any time with reasonable notice. We will endeavor to announce material changes via email or the Platform.

4. Subscription Plans and Billing

4.1 Free Plan

The Free plan provides access to core PDF-to-quiz generation and adaptive practice features at no cost. The Free plan is provided as-is and may be modified or discontinued at our discretion with reasonable notice.

4.2 Premium Plan

The Premium plan provides additional features including: priority concept recommendation, advanced quiz analytics, team management, and priority email support. Pricing for Premium is determined on a per-user or team basis. Contact us at support@rinkuzu.app for custom pricing for teams and institutions.

4.3 Billing and Payment

Payments are processed securely via PayOS. You authorize us to charge your chosen payment method for all fees associated with your Premium subscription. All fees are in USD or VND as displayed at checkout and are non-refundable except as required by applicable law. Recurring subscriptions renew automatically at the end of each billing period unless cancelled at least 7 days before renewal. View our Privacy Policy for payment data handling details.

4.4 Cancellation

You may cancel your Premium subscription at any time through your account settings. Cancellation takes effect at the end of the current billing period. Downgrading to the Free plan does not entitle you to a refund for the current period.

5. Acceptable Use Policy

You agree NOT to use RinKuzu to:

  • Upload, generate, or share content that is unlawful, defamatory, obscene, harassing, discriminatory, or hateful
  • Upload PDF documents you do not own or lack the right to distribute (e.g., copyrighted textbooks without permission)
  • Use the Platform to Spam, distribute malware, or conduct automated scraping beyond personal learning use
  • Attempt to gain unauthorized access to any account, system, or network connected to RinKuzu
  • Use RinKuzu to build a competing product or service without our prior written consent
  • Reverse engineer, decompile, or disassemble any part of the RinKuzu software or AI systems
  • Use AI-generated content from RinKuzu in ways that violate academic integrity policies at your institution
  • Share quiz content from copyrighted textbooks in public quizzes without proper authorization
  • Interfere with or disrupt the integrity or performance of the Platform
  • Violate any applicable local, national, or international law

Violations may result in immediate account suspension or termination, and may be reported to law enforcement authorities where required by law.

6. Content Ownership and Rights

6.1 Your Content

You retain all ownership rights to content you upload to RinKuzu, including PDFs, documents, and any text you submit. By uploading content, you grant us a limited, worldwide, non-exclusive, royalty-free license to process, store, and use that content solely to provide the RinKuzu service to you. We do not claim ownership of your uploaded materials.

6.2 AI-Generated Quizzes

Quizzes and explanations generated by Google Gemini AI through RinKuzu are considered part of the RinKuzu service. You may use AI-generated quizzes for personal study, classroom, or non-commercial educational purposes. Redistribution of AI-generated quiz content as standalone commercial products is prohibited without our prior written consent.

6.3 Community Quizzes

When you create a quiz and set it to “public,” you grant other users a limited license to take and review that quiz within the Platform. You represent that you have the right to share any content included in public quizzes. We reserve the right to remove public quizzes that violate these Terms.

6.4 RinKuzu Intellectual Property

The RinKuzu name, logo, website design, software, algorithms (including SAINT-Bloom knowledge tracing and Dueling DQN curriculum sequencing), and all other RinKuzu proprietary technology are the exclusive property of Hanoi University of Science and Technology. No license to use RinKuzu's intellectual property is granted beyond the limited right to use the Platform as intended.

7. Third-Party Services and Content

RinKuzu uses third-party services including Google Gemini AI, Vercel, and MongoDB Atlas. These services are subject to their own terms and privacy policies. We do not control and are not responsible for the content, accuracy, or practices of any third-party websites or services linked to or from RinKuzu. Your use of third-party services is at your own risk. We recommend reviewing the privacy policies and terms of any third-party services before use.

8. Disclaimer of Warranties

IMPORTANT: PLEASE READ CAREFULLY

RinKuzu is provided “AS IS” and “AS AVAILABLE” without warranties of any kind, express or implied, including but not limited to implied warranties of merchantability, fitness for a particular purpose, title, and non-infringement.

We do not warrant that: (a) the Platform will be uninterrupted, secure, or error-free; (b) AI-generated quizzes will be 100% accurate or free of errors; (c) results obtained from the use of the Platform will meet your specific requirements; or (d) any errors in the software will be corrected. You acknowledge that AI systems are inherently probabilistic and may produce inaccurate, incomplete, or inappropriate content.

9. Limitation of Liability

To the maximum extent permitted by applicable law, in no event shall Hanoi University of Science and Technology, its trustees, officers, employees, agents, or affiliates be liable for any indirect, incidental, special, consequential, or punitive damages, including without limitation:

  • Loss of profits, revenue, goodwill, or anticipated savings
  • Cost of replacement services or data loss
  • Any claim arising from your use of or reliance on AI-generated content
  • Any claim arising from unauthorized access to your account
  • Any act or omission of a third party

Our total cumulative liability arising from or relating to these Terms or your use of RinKuzu shall not exceed the greater of: (a) USD 100 (one hundred United States dollars), or (b) the total fees paid by you to us in the 12 months preceding the event giving rise to the claim.

These limitations apply regardless of whether the claim is based on contract, tort, strict liability, or any other legal theory, and even if we have been advised of the possibility of such damages.

Exceptions: The above limitations do not apply to liability which cannot be limited under applicable law (e.g., Intentional misconduct, gross negligence) or to matters where such limitation would be unenforceable under Vietnamese law or GDPR.

10. Indemnification

You agree to indemnify, defend, and hold harmless Hanoi University of Science and Technology, its trustees, officers, employees, and agents from and against any and all claims, damages, losses, costs, and expenses (including reasonable legal fees) arising from or relating to: (a) your violation of these Terms; (b) your misuse of the Platform; (c) your violation of any third-party right (including intellectual property or privacy rights); or (d) your uploaded content. We reserve the right, at your expense, to assume the exclusive defense and control of any matter subject to indemnification, and you agree to cooperate with our defense.

11. Academic Integrity

RinKuzu is a learning tool designed to support your education. You are responsible for complying with the academic integrity policies of your school, university, or institution. Using RinKuzu to cheat on exams, assignments, or assessments, including generating answers that you submit as your own work without proper attribution, may violate academic integrity policies and could result in disciplinary action by your institution. RinKuzu is not responsible for how you use the Platform in relation to academic requirements at your institution.

12. Governing Law and Dispute Resolution

These Terms are governed by and construed in accordance with the laws of the Socialist Republic of Vietnam, without regard to its conflict of law provisions.

Any dispute arising from or relating to these Terms or your use of RinKuzu shall first be attempted to be resolved through good-faith negotiation between the parties. If the dispute cannot be resolved through negotiation within 30 days, either party may submit the dispute to the competent courts of Hanoi, Vietnam.

For users in the EEA: notwithstanding the above, you may also file a complaint with your local Alternative Dispute Resolution (ADR) body or with the European Commission's Online Dispute Resolution platform.

13. Modifications to Terms

We may modify these Terms from time to time. We will notify you of material changes by posting the updated Terms on this page and updating the “Last updated” date. Material changes will be communicated via email to your registered address at least 14 days before they take effect. Your continued use of RinKuzu after the effective date of any modified Terms constitutes your acceptance of the modified Terms. If you do not agree to the modified Terms, you must stop using the Platform and delete your account.

14. Severability and Waiver

If any provision of these Terms is held to be invalid, illegal, or unenforceable by a court of competent jurisdiction, that provision shall be modified to the minimum extent necessary to make it valid and enforceable, or if modification is not possible, it shall be severed. The remaining provisions shall remain in full force and effect. The failure of either party to enforce any provision shall not constitute a waiver of that provision or any other provision.

15. Contact Information

  • RinKuzu / Hanoi University of Science and Technology
  • Address: Room 302, Building A1, 17 Dai Co Viet Street, Hai Ba Trung District, Hanoi, Vietnam
  • Email: support@rinkuzu.app
  • Website: https://www.rinkuzu.app