Last updated: July 1, 2026

Privacy Policy

Keystone ("the App") is a native macOS application that helps you manage AI-agent rules and skills across your projects. This Privacy Policy explains what information we collect, how we use it, and your rights. In short: Keystone is a local-first tool and is designed to keep your data on your own devices.

1. Information We Collect

Keystone processes your rules, skills, project links, and profiles locally on your device. This content is never transmitted to any server we operate.

The only information that may leave your device:

• iCloud sync data. If you use iCloud, your profiles (your rules and skills libraries) sync between your own Apple devices through Apple's iCloud. This data is stored in your private iCloud account, governed by Apple's Privacy Policy. We have no access to it.
• Feedback submissions. If you choose to send feedback through the in-app form, the submitted data may include your message, an anonymous installation identifier, app version, build number, and macOS version, plus an optional email address. This is sent to our secure feedback backend solely to process your request and improve the App.
• Subscription and purchase data. All purchases and subscriptions are handled entirely by Apple through the Mac App Store. We do not receive or store your payment details. Apple's Privacy Policy governs those transactions.
• Crash reports. If you have opted in to share diagnostics with Apple, anonymized crash reports may be shared with us through Apple's standard developer diagnostics program.

2. Your Project Files

To do its job, Keystone reads and writes rules and skills files inside the folders you explicitly link (for example AGENTS.md, CLAUDE.md, or a .cursor/rules directory). The App only accesses folders you have granted it access to, using standard macOS security-scoped bookmarks. The contents of your projects are processed entirely on your Mac and are never uploaded to us.

3. How We Use Information

• To operate and improve the App.
• To respond to feedback you submit.
• To diagnose and fix crashes or bugs (via anonymized Apple diagnostics data).

We do not sell, rent, or share your information with third parties for marketing purposes.

4. Feedback

When you choose to send feedback, the App collects your message, an anonymous installation ID, app version, and macOS version. You may optionally provide your email address for follow-up. This data is sent to our backend (Supabase) solely to process your feedback and is never used for advertising or shared with third parties.

5. Data Retention

Feedback data is retained only as long as reasonably necessary to operate the feedback channel, respond to inquiries, and improve the App. Retention periods may vary based on operational, security, and legal requirements.

6. Children's Privacy

Keystone is not directed at children under the age of 13. We do not knowingly collect personal information from children. If you believe a child has submitted personal information through the App, please contact us so we can delete it.

7. Third-Party Services

The feedback feature uses a secure backend service (Supabase) to receive and store feedback messages. Supabase processes data in accordance with their own Privacy Policy.

iCloud sync and all App Store transactions are handled by Apple. We do not have access to your iCloud data or your payment information.

8. Your Rights

Because Keystone collects limited personal data, there is little to act on. However, you may:

• Request deletion of any feedback message you have submitted by contacting us.
• Manage or remove your iCloud data in System Settings → your Apple Account → iCloud.
• Opt out of sharing diagnostics with Apple in System Settings → Privacy & Security → Analytics & Improvements.

9. Security

The App runs inside the macOS App Sandbox and accesses only the folders you grant it. Feedback is transmitted over encrypted HTTPS connections and stored securely.

10. Changes to This Policy

We may update this Privacy Policy from time to time. When we do, we will update the "Last updated" date at the top of this page. We encourage you to review this page periodically.

11. Contact

If you have any questions or concerns about this Privacy Policy, please contact us at:
[email protected]