Terms of Service

1. Description of Service

OnUML is an AI-assisted diagram platform for creating, editing, repairing, previewing, saving, and sharing diagram content. Depending on the feature, the service may support Mermaid, PlantUML, Draw.io, and related diagram workflows.

The service may include features such as:

• Generating diagram code from natural-language prompts
• Editing and previewing Mermaid, PlantUML, and Draw.io content
• Cloud project storage, sharing links, and version history
• Exporting diagrams in supported output formats
• AI-powered repair, refinement, and chat-based assistance

2. Accounts and Access

Some features of OnUML may be available without signing in, while others require an account. You are responsible for maintaining the confidentiality of your account credentials and for all activities that occur under your account.

You agree to provide accurate information when creating or maintaining an account. We may suspend or restrict access if we reasonably believe your account is being used in violation of these Terms or in a way that threatens the security or stability of the service.

3. Free and Paid Plans

OnUML currently offers both free and paid access tiers. The Free plan includes most core capabilities at no cost, such as switching between Mermaid, PlantUML, and Draw.io, generating UML from natural-language prompts, using selected basic AI models, sharing projects, saving projects to the cloud, and tracking code history.

Certain advanced features require an active Pro subscription. Based on the current product configuration, Pro features include access to advanced AI models, Mermaid and PlantUML syntax repair, and image uploads in chat.

Plan features, availability, usage limits, and eligibility rules may change over time. If we materially change pricing or paid-plan scope for future periods, we will provide reasonable notice through the service, billing flow, email, or other appropriate channels.

4. Billing, Renewal, and Cancellation

Paid subscriptions are billed in advance on the billing cycle you select, such as monthly or yearly, through supported payment providers. By purchasing a paid plan, you authorize us and our payment providers to charge the applicable subscription fees, taxes, and related charges to your selected payment method.

If a payment fails, we may retry the charge, suspend paid features, or downgrade your access until billing is resolved. You may cancel your subscription through the billing tools made available in the product when supported. Unless otherwise stated in the checkout or required by law, cancellation will take effect at the end of the current paid period and previously charged fees are non-refundable.

5. Acceptable Use

You agree to use OnUML only for lawful purposes and in compliance with these Terms.

You must not:

• Use the service to create, store, or distribute illegal, harmful, or abusive content
• Upload or generate content that infringes intellectual property, privacy, or other rights
• Attempt to reverse engineer, scrape, overload, disrupt, or bypass service protections
• Use bots or automated workflows in a way that unreasonably burdens the platform
• Misrepresent generated output as verified professional, legal, or technical advice
• Use the service in violation of applicable export controls, sanctions, or local laws

We may investigate violations, remove content, refuse processing, limit features, suspend accounts, or terminate access where reasonably necessary to protect users, the platform, or legal compliance.

6. User Content and AI Output

You retain ownership of the content you upload, enter, or create in OnUML, including prompts, project content, and diagram source material, to the extent permitted by law. You represent that you have the necessary rights to submit and use that content.

You are responsible for reviewing AI-generated or AI-repaired output before using, publishing, sharing, or relying on it. AI responses may be incomplete, inaccurate, malformed, or unsuitable for your intended purpose. OnUML does not guarantee that generated diagrams, code, repairs, or analysis will be correct, secure, original, or fit for any specific use case.

You grant OnUML the limited rights necessary to host, process, display, transmit, and transform your content solely for operating, securing, improving, and supporting the service, consistent with our Privacy Policy.

7. Intellectual Property

The OnUML website, branding, software, interface design, service logic, and all related intellectual property rights belong to OnUML or its licensors. Except as expressly allowed by these Terms, you may not copy, distribute, sell, sublicense, or create derivative works from the service itself.

These Terms do not transfer ownership of OnUML technology to you. They only grant you a limited, revocable, non-exclusive right to use the service in accordance with these Terms.

8. Third-Party Services

OnUML may rely on third-party infrastructure and providers, including hosting, authentication, AI model providers, rendering services, analytics, payment processors, and file storage services. Your use of certain features may also be subject to the terms and policies of those third parties.

We are not responsible for outages, policy changes, pricing changes, or data handling practices of third-party services, except as required by applicable law.

9. Availability and Changes

We may update, modify, suspend, or discontinue any part of OnUML at any time, including features, model availability, file limits, pricing, integrations, and supported output formats. We will try to provide advance notice for material changes when reasonably practical, but some updates may be made immediately for security, legal, or operational reasons.

We do not guarantee that the service will always be available, uninterrupted, timely, secure, or error-free.

10. Termination

You may stop using OnUML at any time. We may suspend or terminate your access, with or without notice, if you violate these Terms, create legal or security risk, fail to resolve payment issues, or misuse the platform.

Upon termination, your right to use the service ends immediately. We may retain certain data as required for legitimate business purposes, security, fraud prevention, billing records, or legal compliance.

11. Disclaimers

OnUML is provided on an "as is" and "as available" basis. To the maximum extent permitted by law, we disclaim all warranties, whether express, implied, or statutory, including warranties of merchantability, fitness for a particular purpose, non-infringement, and availability.

We do not guarantee specific business outcomes, engineering correctness, legal compliance of generated content, uninterrupted uptime, or that the service will meet every workflow requirement.

12. Limitation of Liability

To the maximum extent permitted by law, OnUML and its operators, affiliates, licensors, and service providers will not be liable for any indirect, incidental, special, consequential, exemplary, or punitive damages, or for any loss of profits, revenue, data, goodwill, or business opportunities arising out of or related to your use of the service.

To the extent liability cannot be excluded, our total liability for claims arising out of or relating to the service will not exceed the total amount you paid to OnUML for the service during the 12 months preceding the event giving rise to the claim.

13. Changes to These Terms

We may update these Terms from time to time. When we make material changes, we may update the date at the bottom of this page and provide notice through the service or other appropriate channels. Your continued use of OnUML after updated Terms become effective means you accept the revised Terms.

14. Contact Us

If you have questions about these Terms, please contact us at [email protected].