Terms of Service

Last updated: July 6, 2026

1. Acceptance of Terms

By accessing or using ChessMaster ("the Service"), you agree to be bound by these Terms of Service ("Terms"). If you disagree with any part of these terms, you may not access the Service.

2. Description of Service

ChessMaster is a chess-improvement analytics platform. It retrieves your games from chess.com's public API, analyses each move with the Stockfish engine, aggregates the results into weakness, blunder, opening, and time-management analytics, and layers AI coaching on top. The Service integrates with third-party providers, including chess.com (for game data) and Anthropic's Claude API (for coaching text).

3. User Accounts

To use the Service, you must sign in with a supported provider (Google, or optionally Apple). You agree to:

  • Provide accurate account information
  • Maintain the security of your sign-in credentials with your provider
  • Accept responsibility for all activities under your account
  • Notify us immediately of any unauthorised use

4. Third-Party Services

4.1 Chess.com

When you link your chess.com username, we retrieve your publicly available game data through chess.com's public API. We do not ask for or store your chess.com password. Your use of chess.com remains subject to chess.com's own terms and privacy policy, and we access their API as a good-faith, rate-limited client.

4.2 AI Coaching

Coaching text, lessons, blunder reports, and Tutor responses are generated using Anthropic's Claude API from statistics computed about your games. AI output is subject to Anthropic's terms, and you acknowledge that AI-generated content may contain errors.

5. Acceptable Use

You agree not to:

  • Use the Service for any illegal purpose or in violation of any laws
  • Violate any third-party rights, including intellectual property rights
  • Transmit any harmful code, viruses, or malicious software
  • Attempt to gain unauthorised access to the Service or other accounts
  • Interfere with or disrupt the Service or servers
  • Use automated systems to access the Service without permission
  • Link chess.com usernames you do not own or have permission to analyse

6. Your Data

Your chess games remain your own. By using the Service, you grant us a license to:

  • Store and process your game data to provide the Service
  • Analyse your games and generate coaching, analytics, and insights
  • Produce anonymised, aggregate statistics to improve the Service

7. AI Analysis and Coaching

Our engine analysis and AI coaching are provided for informational and educational purposes to help you improve at chess. While we strive for accuracy, engine evaluations and AI-generated coaching may be incomplete or incorrect, and are not guarantees of any particular result or rating improvement.

8. Intellectual Property

The Service, including its original content, features, and functionality, is owned by ChessMaster and protected by applicable intellectual property laws. You may not:

  • Copy, modify, or create derivative works of the Service
  • Reverse engineer or attempt to extract source code
  • Remove any copyright or proprietary notices
  • Use our trademarks or branding without permission

9. Disclaimer of Warranties

THE SERVICE IS PROVIDED "AS IS" AND "AS AVAILABLE" WITHOUT WARRANTIES OF ANY KIND, EITHER EXPRESS OR IMPLIED. WE DISCLAIM ALL WARRANTIES, INCLUDING BUT NOT LIMITED TO MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND NON-INFRINGEMENT. WE DO NOT WARRANT THAT THE SERVICE WILL BE UNINTERRUPTED, SECURE, OR ERROR-FREE.

10. Limitation of Liability

TO THE MAXIMUM EXTENT PERMITTED BY LAW, CHESSMASTER SHALL NOT BE LIABLE FOR ANY INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL, OR PUNITIVE DAMAGES, OR ANY LOSS OF PROFITS OR REVENUES, WHETHER INCURRED DIRECTLY OR INDIRECTLY, OR ANY LOSS OF DATA, USE, GOODWILL, OR OTHER INTANGIBLE LOSSES RESULTING FROM YOUR USE OF THE SERVICE.

11. Termination

We may terminate or suspend your account and access to the Service at any time, for any reason, including if you breach these Terms. Upon termination:

  • Your right to use the Service will cease immediately
  • We may delete your account and data as described in our Privacy Policy
  • All provisions of these Terms that by their nature should survive will survive

12. Changes to Terms

We reserve the right to modify these Terms at any time. We will notify you of material changes by posting the updated Terms on this page and updating the "Last updated" date. Your continued use of the Service after changes become effective constitutes acceptance of the updated Terms.

13. Contact Information

If you have questions about these Terms, please contact us through our Support & Help page or email us at general@ashishgupta.co.uk.