Privacy Policy

CaptionKit Chrome Extension · Last updated: August 23, 2026

CaptionKit is a product of PropKitCo, a brand operated by Byzantine Glam, LLC, a Texas limited liability company. In this policy, “PropKitCo”, “we”, “us”, and “our” refer to Byzantine Glam, LLC.

1. Who We Are

CaptionKit is a Chrome extension operated by PropKitCo. We are the data controller for the personal information you provide while using CaptionKit. You can contact us at areakitpro@gmail.com.

2. What Information We Collect

We collect only the information necessary to provide CaptionKit's features:

Account information: Email address and a hashed password when you sign up. This is managed by Supabase, our authentication provider.
Property data: Property details from listing pages you view (address, price, beds/baths, square footage, features) are read only when the extension is active on a supported listing site (Zillow, Realtor.com, Redfin, MLS). When you generate a caption, this data is sent to our AI provider to generate your caption, cached for up to 24 hours for performance, and not stored permanently.
Usage counts: We track how many AI captions you've used in the current billing period to enforce free-tier limits and Pro subscription benefits.
Payment information: If you upgrade to CaptionKit Pro, payment details (card number, billing address) are collected and processed by Stripe via ExtensionPay. We never see or store your card details.
Authentication tokens: A JWT (JSON Web Token) is stored in your browser's local extension storage to keep you signed in between sessions.

3. What We Do NOT Collect

CaptionKit does not collect, store, or transmit:

Your browsing history
Pages you visit outside of supported listing sites (Zillow, Realtor.com, Redfin, MLS)
Personal data from non-listing pages
Cookies, trackers, or analytics beyond basic usage counts
Location data, IP address (beyond what your ISP normally exposes), or device fingerprints
Information from any other Chrome extensions or browser tabs

4. How We Use Your Information

To generate AI captions: Property data you choose to send is forwarded to Anthropic's Claude API, which generates platform-optimized captions and hashtags. The AI provider processes this data ephemerally and does not retain it for training.
To enforce usage limits: We count captions per billing period to ensure free-tier users get exactly 3 captions per month and Pro subscribers get unlimited access.
To authenticate you: Your email and password (handled by Supabase) verify your identity across browser sessions.
To process payments: If you upgrade, we share your email with ExtensionPay/Stripe to manage your subscription.

5. Third-Party Services

CaptionKit relies on the following third parties to function. Each has its own privacy policy:

Supabase — authentication and user accounts. Privacy policy
Anthropic (Claude) — AI text generation. Per Anthropic's API terms, your prompts are not used for training and are deleted after a short retention period. Privacy policy
ExtensionPay — subscription management for the Pro plan. Privacy policy
Stripe — payment processing. Privacy policy
Vercel — hosting our backend API. Privacy policy

6. Data Storage and Retention

Account data (email, hashed password) is stored in Supabase indefinitely until you request deletion.
Generated AI captions are cached in our database for up to 24 hours to avoid re-charging users for identical inputs. After 24 hours, the cache is purged.
Property data sent for generation is not stored permanently — only the cache key (a hash of the input) is retained for the 24-hour cache window.
Usage counts are stored in our database for billing-period tracking and historical reporting (up to 12 months).
Payment records are retained per legal/tax requirements (typically 7 years) by Stripe.

7. Your Rights

You have the right to:

Access the personal data we hold about you
Correct inaccurate information in your account
Delete your account and all associated data
Export your data in a machine-readable format
Withdraw consent for AI processing at any time (you can stop using the extension)
Lodge a complaint with your local data protection authority (EEA users)

To exercise any of these rights, email areakitpro@gmail.com with your request. We respond within 30 days.

8. Children's Privacy

CaptionKit is intended for use by real estate professionals 18 years of age or older. We do not knowingly collect personal data from children under 18. If you believe a child has provided us with personal information, contact us and we will delete it promptly.

9. International Data Transfers

CaptionKit is operated from the United States. If you are accessing the service from outside the U.S., be aware that your information will be transferred to, stored, and processed in the United States. Our third-party providers (Supabase, Anthropic, Vercel, Stripe) may also store data in the U.S. and other jurisdictions in compliance with applicable data protection laws (including the EU-U.S. Data Privacy Framework where applicable).

10. Security

We use industry-standard security measures to protect your data:

All API requests use HTTPS encryption
Passwords are hashed using bcrypt by Supabase
Authentication tokens are stored in Chrome's secure extension storage
Row-level security on our database ensures users can only access their own data
API keys for AI providers are never exposed to the browser

11. Changes to This Policy

We may update this Privacy Policy to reflect changes in our practices or legal obligations. The “Last updated” date at the top of this page indicates when the latest changes took effect. For material changes, we will notify you via email or via a notice in the extension.

12. Contact Us

For any privacy-related questions or to exercise your rights:

PropKitCo (Byzantine Glam, LLC)
Email: areakitpro@gmail.com