Terms of Service

These Terms of Service (the "Terms") are an agreement between RedHold LLC, a Virginia limited liability company operating as Diagrams.so ("Diagrams.so", "we", "us"), and the person or organization using our services ("you"). They cover everything we offer: the diagrams.so website and web application, our backend, and the public API at api.diagrams.so (together, the "Services"), however you access them, including through our open-source MCP server and SDKs.

Our notice address is RedHold LLC, 8401 Mayland Dr, STE S, Richmond, VA 23294, USA. For legal notices, write to legal@diagrams.so.

By creating an account, creating an API key, or using the Services, you accept these Terms. If you use the Services on behalf of an organization, you confirm that you are authorized to bind it, and "you" includes that organization. These Terms replace all earlier versions of our website terms.

1. The documents that apply to you

1.1 The following policies are part of these Terms, each at its published URL as updated from time to time:

• Acceptable Use Policy: diagrams.so/policy/acceptable-use
• Privacy Policy: diagrams.so/policy/privacy, and Cookie Notice: diagrams.so/policy/cookies
• Refunds and Billing Policy: diagrams.so/policy/refunds
• Copyright and Content Complaints Policy: diagrams.so/policy/copyright
• Trademark Policy: diagrams.so/policy/trademark

For customers who submit personal data for us to process on their behalf, the Data Processing Addendum at diagrams.so/policy/dpa is automatically part of these Terms where it applies.

1.2 If we publish supplemental terms for a specific feature or program, those control for that feature only, to the extent of a direct conflict. Otherwise these Terms control over the incorporated policies, and the policies control over documentation. Documentation describes the product and is not a contract, except where these Terms say otherwise (Section 12). For personal data within its scope, the Data Processing Addendum controls over these Terms.

2. Definitions

• "Input" means prompts and other content you submit, in the formats the product accepts, including imported diagram files and voice input where offered.
• "Output" means the diagrams, files, warnings, scores, transcriptions, and other content the Services generate for you.
• "API Key" means a dgz_live_ (live mode) or dgz_test_ (test mode) credential that authenticates your requests.
• "Credits" means the prepaid usage allowance described in Section 4.
• "Official Clients" means our open-source MCP server and SDKs, which are client software for the Services.
• "Provider" means a third-party AI provider we route requests to (Section 8).

3. Accounts, keys, and eligibility

3.1 We grant you a non-exclusive, non-transferable right to use the Services under these Terms. The Official Clients are licensed separately under their own open-source licenses (currently Apache-2.0). Those licenses govern the client code only; these Terms govern the Services the clients connect to.

3.2 API Keys are secrets, shown once at creation. You are responsible for keeping your keys confidential and for all use under your keys and your account, including use by anyone you give access to. Do not place a live key in client-side code or a public repository. You can revoke a key at any time; revocation is immediate. We may revoke any key immediately if we believe it is compromised, exposed, or being used in violation of these Terms or the Acceptable Use Policy.

3.3 Test-mode keys exist for integration testing at a lower rate limit. Billable actions on a test-mode key draw from the same Credit balance as a live key. There is no separate free sandbox. Treat test-mode keys with the same care as live keys.

3.4 You must be at least 18 years old and able to form a binding contract. The Services are not directed to anyone under 18.

3.5 Features labeled beta, preview, early access, or experimental are provided as is, may change or be withdrawn at any time, and are excluded from the deprecation commitments in Section 12. A beta label applies to the specific feature or endpoint marked, never to the Services as a whole.

3.6 If you send us feedback about the Services, we may use it without restriction or obligation to you.

4. Plans, Credits, and billing

4.1 Access is organized into plan tiers. Current plans, prices, features, and Credit amounts are listed on the pricing page at diagrams.so/pricing, which we may update. Diagrams created on the Free plan are public (Section 5.5).

4.2 Credits are a prepaid usage allowance. They have no cash value, are not transferable or redeemable for money, and are not a stored-value or deposit product. Your balance is shared across the web app, the API, and the Official Clients, and across live and test-mode keys. Generation and editing actions consume Credits based on metered usage; reads, exports, and helper operations are free. A request that fails before delivering a result is not charged.

4.3 Credit types work as follows. Free plan Credits are a one-time grant at signup and do not refresh. Monthly plan Credits refresh each billing period; unused monthly Credits roll over up to a plan-specific cap and expire 30 days after the start of the next billing period. Add-on Credit packs do not expire. Credits are consumed in this order: bonus, rolled-over, monthly, add-on.

4.4 There is no overage billing. When your balance reaches zero, billable actions are refused until your next grant, an add-on purchase, or an upgrade. We never charge you for usage beyond the Credits you already hold, and there is no auto-recharge.

4.5 Fees are charged through Stripe. Subscriptions renew automatically each period until cancelled; you can cancel at any time from account settings or the billing portal, and you keep access through the end of the paid period. Your first paid subscription purchase includes a 14-day money-back guarantee. Refunds, cancellation mechanics, and consumer withdrawal rights are described in the Refunds and Billing Policy. You are responsible for applicable taxes other than our income taxes. Prices may change prospectively with reasonable notice.

4.6 You may not circumvent Credit metering, rate limits, or quotas, including by rotating keys, IP addresses, or accounts.

5. Your content and our content

5.1 Your Inputs stay yours. You grant us a worldwide, royalty-free license to host, process, and transmit your Inputs solely to provide, secure, and maintain the Services, including routing them to a Provider to generate Output, as described in the Privacy Policy.

5.2 As between you and us, you own the Output generated for you, and we assign to you all of our right, title, and interest, if any, in that Output. This assignment is conditioned on your compliance with these Terms, which mirrors the conditions our Providers place on us. Generative systems are probabilistic, so the same or similar Output may be generated for other users, and we make no promise of uniqueness or exclusivity.

5.3 Verify Output before you rely on it. Output is generated by AI and can be wrong, incomplete, or unsuitable for production. Architecture warnings and scores are automated heuristics, not professional advice. You must review and verify Output, including any factual or security claims in it, before relying on it or presenting it to others. This obligation also appears in our documentation because our Providers require us to state it in both places.

5.4 We do not train AI models on your Inputs or Outputs, and our Providers are contractually restricted from training on content submitted through our accounts. We may use aggregated, de-identified usage data to operate and improve the Services.

5.5 Content you make public. Diagrams created on the Free plan are published at creation and cannot be made private; private diagrams are a paid feature. Public diagrams appear in the community gallery and on share pages, can be indexed by search engines, and can be viewed, exported, and forked by others. Your prompt text is never displayed on public surfaces. When a diagram of yours is public, you grant us a worldwide, royalty-free license to host, display, reproduce, and promote it as part of the Services, and you grant other users a non-exclusive license to view, export, fork, and adapt it within the Services. Forks made while a diagram was public belong to the users who made them and survive your later unpublishing or deletion. Do not put confidential or personal information in a public diagram.

5.6 If you believe content on the Services infringes your copyright or is otherwise unlawful, use the process in our Copyright and Content Complaints Policy or write to dmca@diagrams.so. We may remove or disable access to content that violates these Terms or the law, and we will, in appropriate circumstances, terminate the accounts of repeat infringers.

5.7 "Diagrams.so", "RedHold", and our logos are our trademarks. These Terms grant no rights in them. Permitted uses are described in the Trademark Policy.

6. Rules that come from our AI Providers

Our Providers hold us responsible for how the Services are used downstream, so you agree to the following, and you will impose them on anyone you give access to. These commitments are conditions of your license and of the Output assignment in Section 5.2.

(a) Comply with the usage policies of the Providers we route to, as updated, including the Anthropic Usage Policy and the OpenAI Usage Policies. The current Provider list is at diagrams.so/policy/subprocessors.

(b) Verify Output as described in Section 5.3, and do not present Output as verified or as wholly human-created.

(c) Where you show Output to other people, disclose that it is AI-generated where law or Provider policy requires.

(d) Do not provide the Services, or products built on them, to anyone under 18.

(e) Do not use the Services or Output to train, improve, or build a competing AI model or diagramming service, and do not extract, scrape, or reverse-engineer the underlying models, system prompts, or scoring logic.

(f) Do not bypass or disable safety systems, rate limits, or metering. If we or a Provider notify you that particular Output is subject to an infringement claim, stop using that Output promptly.

(g) Do not sell, share, sublicense, or transfer API Keys or API access, and do not operate the Services as a raw pass-through or proxy to an AI provider. Building a genuine product on top of the Services is welcome.

(h) If you use Output in legal, health, financial, insurance, employment, or similarly high-stakes contexts affecting individuals, a qualified person must review it and the AI's role must be disclosed, as Provider policies require. Do not use the Services to make automated decisions with legal or similarly significant effects on individuals without qualified human oversight.

(i) Comply with the sanctions and export rules in Section 14.2.

(j) You confirm that you have the rights needed to submit your Inputs and that they do not infringe anyone's rights.

You will also comply with the Acceptable Use Policy and all applicable laws.

7. Privacy

Our handling of personal data is described in the Privacy Policy, which controls over any summary here. In short: the prompt that produces a diagram is stored with that diagram and its versions, privately to your account; public surfaces never display prompt text; voice recordings are transcribed and the audio is not stored by us; and account deletion works as described in the Privacy Policy, including its limits. Business customers may rely on the Data Processing Addendum.

8. Third-party AI Providers

The Services route generation and transcription requests to third-party AI Providers. The current Providers, and everything else about how they process your content, are listed at diagrams.so/policy/subprocessors and in the Privacy Policy. We may add, remove, or re-route among Providers to operate the Services; we update the subprocessor page before adding a new one. The obligations Providers impose on downstream use are the ones in Section 6.

9. Confidentiality

Non-public information one party discloses to the other is confidential, may be used only under these Terms, and must be protected with reasonable care. This does not apply to information that is public, independently developed, or rightfully received from someone else. Either party may disclose confidential information when legally required, with prompt notice where permitted.

10. Term, suspension, and termination

These Terms apply for as long as you use the Services. You can stop using the Services and delete your account at any time. Either party may terminate for material breach that remains uncured 30 days after notice. We may act immediately, without prior notice, where needed to address violations of the Acceptable Use Policy, security risk, abuse of metering or billing, non-payment, repeat infringement, or legal requirements. The actions available to us include revoking API Keys, blocking sign-in, removing content from public surfaces, and terminating the account. On termination, your right to use the Services ends and unused Credits are handled per Section 4.3 and the Refunds and Billing Policy. Sections 3.6, 4 (for amounts accrued), 5.2 through 5.7, 9, 11, 12.3, 13, 14, and 15 survive termination.

11. Disclaimers and limitation of liability

11.1 THE SERVICES AND ALL OUTPUT ARE PROVIDED "AS IS" AND "AS AVAILABLE", WITHOUT WARRANTIES OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NON-INFRINGEMENT, AND ANY WARRANTY THAT OUTPUT IS ACCURATE, COMPLETE, SECURE, OR SUITABLE FOR PRODUCTION USE. WE DO NOT PROMISE UNINTERRUPTED OR ERROR-FREE OPERATION AND OFFER NO SERVICE-LEVEL COMMITMENT. See the Service Level and Support statement at diagrams.so/policy/support.

11.2 TO THE MAXIMUM EXTENT PERMITTED BY LAW: (a) NEITHER PARTY IS LIABLE FOR INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL, EXEMPLARY, OR PUNITIVE DAMAGES, OR FOR LOST PROFITS, REVENUE, OR DATA; AND (b) EACH PARTY'S TOTAL AGGREGATE LIABILITY ARISING OUT OF OR RELATING TO THESE TERMS OR THE SERVICES WILL NOT EXCEED THE GREATER OF (i) THE FEES YOU PAID US IN THE TWELVE MONTHS BEFORE THE EVENT GIVING RISE TO THE CLAIM AND (ii) ONE HUNDRED US DOLLARS (USD 100). FOR USE FOR WHICH YOU HAVE PAID US NOTHING, INCLUDING THE FREE PLAN, OUR TOTAL AGGREGATE LIABILITY WILL NOT EXCEED THE AMOUNTS YOU HAVE PAID US FOR THE SERVICES, AND WHERE THAT AMOUNT IS ZERO WE HAVE NO LIABILITY FOR DAMAGES OF ANY KIND TO THE FULLEST EXTENT THE LAW ALLOWS.

11.3 These limits do not apply to your payment obligations, to your indemnity in Section 13, or to liability that cannot be limited by law. If you are a consumer, nothing in these Terms limits rights that the law of your country of residence does not allow to be limited.

12. Changes to the Services, the API, and these Terms

12.1 We may change the Services. The public API at api.diagrams.so is versioned: within a major version we make only backward-compatible changes, and a breaking change ships as a new major version.

12.2 If we retire an API major version or a documented, generally available API capability, we will use commercially reasonable efforts to give at least 90 days' notice before shutdown. This commitment does not apply to changes required by law or a Provider's terms, changes needed to address security or abuse, or beta features. Our operating policy, with longer target windows and migration guidance, is published at diagrams.so/policy/deprecation; that policy describes our practice and this Section 12.2 is the contractual commitment.

12.3 We may update these Terms prospectively. For material changes we will give at least 30 days' notice by email to your account address before the new terms take effect. If you do not agree, stop using the Services before the effective date. Continued use after the effective date is acceptance.

13. Indemnification

You will defend and indemnify us against third-party claims, and the resulting damages, costs, and reasonable attorneys' fees, arising from your Inputs, your use of Output, your products and the people you give access to, or your breach of Section 6, the Acceptable Use Policy, or applicable law.

14. Governing law and miscellaneous

14.1 These Terms are governed by the laws of the State of Virginia, USA, without regard to conflict-of-law rules. The exclusive venue for any dispute is the state courts sitting in Henrico County, Virginia, or the United States District Court for the Eastern District of Virginia, Richmond Division, and both parties consent to personal jurisdiction there. Any claim arising out of or relating to these Terms or the Services must be filed within six months after it accrues or it is permanently barred. If you are a consumer, this section does not displace mandatory venue or limitation rules of your country of residence.

14.2 You represent that you are not located in, and will not use or make the Services available in, Cuba, Iran, North Korea, Syria, or the Crimea, Donetsk, or Luhansk regions, and that you are not on any US government restricted-party list. You will comply with US export control and sanctions laws.

14.3 You may not assign these Terms without our consent; we may assign them to an affiliate or in connection with a merger, acquisition, or sale of assets. If a provision is unenforceable, the rest remains in effect. A delay in enforcing a right is not a waiver of it. Neither party is liable for delay or failure caused by events beyond its reasonable control.

14.4 These Terms, the documents listed in Section 1.1, and the Data Processing Addendum where it applies are the entire agreement between us about the Services and supersede all earlier agreements on the subject, including any previously published website terms.

14.5 Formal notices to us must be sent to legal@diagrams.so or to our postal address above. We may send notices to your account email address. Email notices are considered received the next business day after sending.

14.6 These Terms create no rights in any third party, and nothing in them creates a partnership, joint venture, agency, or employment relationship.

15. Contact

Questions about these Terms: legal@diagrams.so. Support: support@diagrams.so. All of our policies are listed at diagrams.so/policy.