Terms & Conditions

Last updated: April 15, 2026

These Terms & Conditions (“Terms”) are a binding agreement between you (“you”) and Chapter Inc. (“Chapter”, “we”, “us”, or “our”) that govern your use of Vargus, including the open-source command-line tool, the web dashboard at vargus.com, and any related services, documentation, and APIs (together, the “Service”).

By installing, accessing, or using the Service you agree to these Terms. If you are using the Service on behalf of an organisation, you represent that you have authority to bind that organisation and “you” refers to that organisation. If you do not agree to these Terms, do not use the Service.

1. Who we are

Chapter Inc. is a Delaware corporation. You can contact us at hello@chapter.com.

2. The Service

Vargus is an AI-native QA testing toolchain that orchestrates large language model agents to run intent-level tests against your applications. The Service consists of:

  • an open-source command-line tool distributed under the MIT License, installed and run on your own infrastructure;
  • a hosted web dashboard for reviewing runs, results, and related data; and
  • optional APIs and integrations that connect the CLI to the dashboard and to third-party AI model providers.

We may change, suspend, or discontinue any part of the Service at any time, with reasonable notice for paid plans.

3. Accounts

Some features require you to create an account or sign in through a third-party identity provider. You must provide accurate information, keep your credentials confidential, and promptly notify us of any unauthorised use of your account. You are responsible for all activity that occurs under your account.

4. Open-source licence (CLI)

The Vargus command-line tool is released under the MIT License. Your use of the CLI itself is governed by that licence, which is included with the source code. These Terms apply to the hosted Service and to your use of the CLI where it interacts with the hosted Service or third-party AI model providers via Chapter-supplied credentials.

5. Licence to use the Service

Subject to your compliance with these Terms, we grant you a limited, non-exclusive, non-transferable, non-sublicensable licence to access and use the Service for your internal testing and development purposes. We reserve all rights not expressly granted.

6. Acceptable use

You agree not to, and not to permit any third party to:

  • use the Service in violation of any applicable law, regulation, or third-party right;
  • use the Service to test, probe, attack, or scrape a system, website, or API that you do not own or have explicit written permission to test;
  • use the Service to generate, transmit, or store content that is unlawful, infringing, defamatory, harassing, or that contains malware;
  • bypass or attempt to bypass rate limits, usage caps, access controls, or security measures;
  • reverse-engineer, decompile, or attempt to derive the source code of any closed-source component of the Service (except to the extent such restrictions are prohibited by applicable law);
  • resell, sublicense, or make the hosted Service available to third parties as a standalone product;
  • use the Service to train a competing AI model or product; or
  • use the Service in a way that materially impairs its availability, integrity, or security for other users.

You are solely responsible for the systems you test with Vargus and must have all necessary rights and permissions to do so.

7. AI-generated output and test results

Vargus orchestrates large language model agents to generate test scenarios, execute tests, and produce reports. AI-generated output can be inaccurate, incomplete, or misleading and may not reflect current facts. Vargus test results are provided to assist your quality-assurance process; they are not a guarantee that your software is free of defects, vulnerabilities, or non-conformities.

You are solely responsible for reviewing AI-generated output, validating test results, and deciding whether to rely on them. Do not use the Service as the sole basis for any decision with legal, safety, financial, medical, or similarly material consequences.

8. Your content

“Your Content” means any data you submit to the Service, including test scenarios, configuration, source references, URLs, credentials you choose to supply, and any data accessed during a test run. As between you and us, you retain all rights in Your Content.

You grant us a worldwide, non-exclusive, royalty-free licence to host, copy, transmit, display, and process Your Content solely to provide, secure, and improve the Service on your behalf, to comply with legal obligations, and to produce aggregated, anonymised analytics that cannot be used to identify you or your users. We will not use Your Content to train AI models.

You represent that you have all rights necessary to submit Your Content to the Service and that Your Content, and our authorised use of it, will not infringe any third-party right or violate any law.

9. Third-party services

The Service integrates with third-party providers, including AI model providers such as Anthropic, hosting providers, payment processors, and identity providers. Your use of those services is subject to their own terms and privacy policies. We are not responsible for third-party services or for any changes they make to their offerings. If a third-party service becomes unavailable or changes its terms, we may suspend or modify the corresponding feature of the Service.

10. Fees, subscriptions, and billing

Parts of the Service are available free of charge. Paid plans are billed in advance on a recurring basis (monthly or annual) at the rates shown at the time of purchase. All fees are stated exclusive of applicable taxes, which you are responsible for paying.

Paid plans renew automatically at the end of each billing period unless you cancel before the renewal date. You can cancel at any time through the dashboard; cancellation takes effect at the end of the then-current billing period and you will retain access until then. Except where required by law, fees are non-refundable.

Some features meter usage (for example, AI tokens consumed during test runs). Usage-based charges are billed in arrears based on records maintained by us and our AI model providers, which will be conclusive absent manifest error. We may change pricing with at least 30 days’ notice; changes apply to the next renewal.

11. Intellectual property

The Service and all related software, designs, text, graphics, and content (other than Your Content and open-source components) are owned by Chapter Inc. or its licensors and are protected by intellectual property laws. Except for the rights expressly granted in these Terms and any applicable open-source licences, no rights are transferred or licensed to you. “Vargus”, “Chapter”, and associated logos are trademarks of Chapter Inc.

12. Feedback

If you send us feedback, suggestions, or ideas about the Service, you grant us a perpetual, irrevocable, worldwide, royalty-free licence to use and incorporate that feedback without any obligation to you.

13. Disclaimers

The Service is provided “as is” and “as available”. To the maximum extent permitted by law, Chapter disclaims all warranties, whether express, implied, statutory, or otherwise, including any implied warranties of merchantability, fitness for a particular purpose, title, non-infringement, and any warranties arising from course of dealing or usage of trade.

Chapter does not warrant that the Service will be uninterrupted, error-free, or secure, that defects will be corrected, or that AI-generated output will be accurate, complete, or reliable. You are responsible for evaluating whether the Service is suitable for your use case.

14. Limitation of liability

To the maximum extent permitted by law, in no event will Chapter, its affiliates, or their respective officers, directors, employees, or agents be liable for any indirect, incidental, special, consequential, exemplary, or punitive damages, or for any loss of profits, revenue, data, goodwill, or business opportunity, arising out of or related to these Terms or the Service, whether based on contract, tort (including negligence), strict liability, or any other legal theory, and whether or not we have been advised of the possibility of such damages.

Chapter’s total cumulative liability arising out of or related to these Terms and the Service will not exceed the greater of (a) the amounts paid by you to Chapter for the Service in the twelve months immediately preceding the event giving rise to the liability, or (b) one hundred US dollars (USD 100).

Nothing in these Terms excludes or limits any liability that cannot be excluded or limited under applicable law, including liability for death, personal injury caused by negligence, fraud, or fraudulent misrepresentation.

15. Indemnification

You agree to defend, indemnify, and hold harmless Chapter and its affiliates from and against any third-party claims, liabilities, damages, losses, and expenses (including reasonable legal fees) arising out of or related to (a) your use of the Service in breach of these Terms, (b) Your Content, (c) the systems and applications you test using the Service, or (d) your violation of any applicable law or third-party right. We will promptly notify you of any such claim and cooperate reasonably with your defence.

16. Termination

You may stop using the Service at any time and may cancel a paid plan through the dashboard. We may suspend or terminate your access to the Service at any time, with or without notice, if we reasonably believe that you have breached these Terms, that continued use poses a security or legal risk, or that we are required to do so by law. On termination, your right to use the Service ends immediately and we may delete Your Content after a reasonable retention period. Sections 7, 8 (last paragraph), 11-15, 17, and 18 survive termination.

17. Changes to these Terms

We may update these Terms from time to time. When we do, we will revise the “Last updated” date at the top of this page and, where the changes are material, notify you by email or through the Service at least 14 days before they take effect. If you do not agree to the updated Terms, your only remedy is to stop using the Service; continued use after the effective date constitutes acceptance.

18. Governing law and disputes

These Terms are governed by the laws of the State of Delaware, United States, without regard to its conflict-of-laws rules. Any dispute arising out of or relating to these Terms or the Service will be brought exclusively in the state or federal courts located in Delaware, and each party consents to the personal jurisdiction of those courts, except that either party may seek injunctive relief in any competent court.

Nothing in this section deprives a consumer of the protection of the mandatory laws of their country of residence.

19. General

  • Entire agreement. These Terms, together with our Privacy Policy and any order form or plan you sign up to, are the entire agreement between you and Chapter regarding the Service.
  • No waiver. Failure to enforce any provision is not a waiver of the right to enforce it later.
  • Severability. If any provision is held unenforceable, the remaining provisions will remain in full effect.
  • Assignment. You may not assign these Terms without our prior written consent. We may assign them in connection with a merger, acquisition, or sale of assets.
  • Force majeure. Neither party is liable for any failure or delay caused by events beyond its reasonable control.
  • No agency. These Terms do not create any agency, partnership, joint venture, or employment relationship between the parties.

20. Contact

Questions about these Terms should be sent to hello@chapter.com.