Terms of Service.

These Terms of Service ("Terms") are between you and Quinn Otto, trading as Zevyn Studio ("Zevyn Studio", "we", "us"), the operator of the desktop app and the website at zevyn.dev (the "Service"). By installing the desktop app or by creating an account on zevyn.dev, you agree to these Terms.

You must be at least 16 years old to use the Service. If you're using it on behalf of an organisation, you confirm you have authority to bind that organisation, and "you" refers to both you and the organisation.

Zevyn Studio is a desktop application that orchestrates AI coding agents on your own machine. We provide the workspace — supervisor, worktrees, memory graph, review console. You bring your own AI model API keys (Anthropic, OpenAI, etc.). Your prompts and your code do not pass through our servers.

The website at zevyn.dev hosts marketing pages, documentation, authentication, and subscription management. The desktop app talks to zevyn.dev for sign-in and to verify your subscription status.

• You sign in with an email magic link or with GitHub OAuth. Keep your inbox and your OS keychain secure — anyone with access to them can sign in as you.
• One paid seat covers one installation on one machine. Agents spawned from that installation are local processes and do not consume additional seats.
• Sharing credentials, refresh tokens, or signed subscription claims between machines or between people is not permitted. We may suspend accounts that do.
• You're responsible for activity on your account. If you suspect your account has been compromised, email [email protected].

• Plans and prices: Solo €5/mo, Pro €25/mo, Team €50/seat/mo. Listed prices are exclusive of VAT unless stated otherwise.
• Billing is monthly in advance via Stripe. Your subscription renews automatically until you cancel.
• VAT and other applicable consumption taxes are calculated and remitted by Stripe Tax based on the billing address you give Stripe. The total you pay is shown before checkout.
• Prices may change. Existing subscribers get at least 30 days' notice by email before a price change takes effect, and may cancel before the new rate applies.
• The first month of Solo is free and does not require a card. If you do not start a paid plan, paid features simply stop at the end of the free month.

You can cancel at any time from the Stripe Customer Portal, linked from your account page on zevyn.dev. Cancellation takes effect at the end of the current billing period — you keep access until then. We do not pro-rate cancellations on monthly plans.

After cancellation, the desktop app keeps working in its free-tier mode: local-first features remain usable, paid features lock once your current signed claim expires.

• Within the first 7 days of your first paid subscription, we refund in full on request, no questions asked. Email [email protected].
• After those 7 days, we do not issue refunds for unused time on a monthly plan. The remaining time is your access until the period ends.
• If the Service is materially unavailable for an extended period, we may, at our discretion, refund or credit specific charges affected by the outage.
• Refunds are issued to the original payment method via Stripe and typically appear within 5–10 business days.

Our 7-day refund (§6) goes further than the statutory minimum for fully-performed digital services. Nothing in these Terms limits non-waivable rights you have under the consumer-protection law of your country of residence.

Don't use the Service to:

• Break applicable law, infringe anyone's rights, or generate content prohibited by your chosen model provider's terms.
• Reverse-engineer the Service, attempt to extract source code from compiled binaries, or interfere with other users' access.
• Resell the Service or wrap it as a third-party offering without our prior written consent.
• Use AI model keys you don't have a valid licence to use, or use the Service to bypass another provider's rate limits or terms.
• Probe, scan, or load-test the website or auth infrastructure without prior written permission.

We may suspend or terminate accounts that violate these clauses. Where reasonable, we give notice and a chance to fix the issue first.

You retain ownership of your code, your prompts, and the outputs your agents produce. The desktop app processes them locally; we do not see them or store them on our servers. Anything you send to an AI model provider is governed by that provider's terms, not ours.

Your model API keys are stored in your OS keychain on the device that uses them. We never receive your keys. If your key is exposed or charged for usage you did not authorise, that is between you and the model provider — but tell us if it happened because of a bug in the Service.

Zevyn Studio — the application, the brand, the documentation, and the marketing site — is owned by Quinn Otto, trading as Zevyn Studio and protected by copyright and trademark law. Your subscription grants you a non-exclusive, non-transferable licence to install and run the app for the term of your subscription. The licence ends when your subscription ends.

We aim for high availability of the auth and subscription endpoints, but do not promise specific uptime. The desktop app is designed to keep working offline: local features always work, and paid features stay unlocked for up to 7 days after the last successful subscription check using a server-signed claim cached on disk. Outside that window, paid features lock until the app can reach our servers again.

The Service is provided "as is" and "as available". To the maximum extent permitted by law, we disclaim implied warranties of merchantability, fitness for a particular purpose, and non-infringement. We do not warrant that the Service will be uninterrupted, error-free, or that any specific output of an AI model will be accurate or fit for any particular purpose.

Nothing in this section limits warranties or rights that cannot be waived under the consumer-protection law applicable to you.

To the maximum extent permitted by law, our total aggregate liability for any claim relating to the Service is capped at the greater of (a) one hundred euros (€100) or (b) the fees you paid us in the 12 months preceding the claim. We are not liable for indirect, incidental, consequential, special, or punitive damages — including lost profits, lost data, or business interruption.

Nothing in this section excludes or limits liability that cannot be excluded or limited by applicable law, including liability for gross negligence, wilful misconduct, fraud, or for death or personal injury caused by our negligence.

You can stop using the Service and delete your account at any time from the account page. We may terminate your access for material breach of these Terms (including §8 Acceptable use), for non-payment after a reasonable grace period, or if continuing to provide the Service to you becomes legally impractical. Termination does not affect liabilities that have already accrued.

These Terms are governed by the laws of the Netherlands, without regard to its conflict-of-laws rules. Any dispute arising out of or in connection with these Terms goes to the exclusive jurisdiction of the competent courts of Rotterdam, without prejudice to any non-waivable right of an EU consumer to bring proceedings in the courts of their country of residence and under the law of that country.

We may update these Terms from time to time. Material changes are announced by email to registered users at least 30 days before they take effect; the date at the top of this page is updated when changes go live. Continued use of the Service after the change date means you accept the updated Terms. If you do not accept, cancel your subscription before the change date — §6 refunds still apply where relevant.

• Severability: if any provision of these Terms is found to be invalid or unenforceable, that provision is modified to the minimum extent necessary to make it enforceable, and the remaining provisions continue in full force.
• Assignment: you may not assign your rights or obligations under these Terms without our prior written consent. We may assign these Terms in connection with a merger, acquisition, or sale of all or substantially all of our assets, with 30 days' notice to you.
• No waiver: failing to enforce any provision of these Terms on one occasion does not waive our right to enforce it on another.
• Entire agreement: these Terms and the Privacy Policy at zevyn.dev/privacy constitute the entire agreement between us regarding the Service and supersede any prior agreements.

Questions about these Terms, refunds, or anything else: [email protected]. Postal: Quinn Otto, trading as Zevyn Studio, 3145CR Maassluis, the Netherlands.

EU consumers may also use the European Commission's Online Dispute Resolution platform at https://ec.europa.eu/consumers/odr to resolve disputes out of court.