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PRIVACY POLICY - CHESS VISION PRO ASSISTANT
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Effective Date: October 31, 2026
Last Updated: October 31, 2026
At Chess Vision Pro ("we", "us", or "our"), user privacy and data security are our highest priorities. We are committed to complete transparency, zero data harvesting, and strictly local, client-side functionality.
This Privacy Policy explains how our extension operates, details how and why browser permissions are utilized, and provides an affirmative, in-depth explanation of why each requested permission is strictly necessary.
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1. OUR CORE PRIVACY COMMITMENTS
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• ZERO PERSONAL DATA COLLECTION: We do not collect, harvest, monitor, store, sell, or transmit any personal information, browsing history, login credentials, or personal gameplay records.
• 100% LOCAL & CLIENT-SIDE EXECUTION: All chess engine evaluations, board scanning, calculations, and UI rendering take place on your local machine within your browser sandbox.
• NO EXTERNAL TRACKING OR ANALYTICS: The extension contains zero third-party telemetry, tracking scripts, Google Analytics, advertising libraries, or remote fingerprinting tools.
• COMPLETELY AD-FREE: The extension does not inject ads, display promotional banners, or redirect search queries.
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2. INFORMATION WE DO NOT ACCESS OR COLLECT
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To eliminate all ambiguity, Chess Vision Pro NEVER accesses, logs, or transmits:
• Your name, email address, password, or Chess.com credentials.
• Your financial, payment, or subscription details.
• Your browsing history, visited websites, or tabs other than active Chess.com game sessions.
• Your device hardware identifiers, MAC address, or operating system fingerprints.
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3. PERMISSION BREAKDOWN & TECHNICAL JUSTIFICATIONS
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The extension requests only two permissions in its manifest.json. Below is an exhaustive explanation of what they do and why they are required:
1. "storage" (Chrome Storage API)
• Technical Purpose: Provides access to `chrome.storage.local` within the extension sandbox.
• Usage: Used exclusively to save your customized preferences (such as engine calculation depth, auto-move toggles, randomized delay intervals, visual overlay styles, arrow colors, and in-game HUD window coordinates) so your settings persist between browser sessions.
• Scope: Data is stored solely on your local device. It is never synchronized to external cloud databases or third-party servers.
2. Host Permission ("https://www.chess.com/*")
• Technical Purpose: Allows the extension's content scripts (`content.js` and `content-bridge.js`) to run strictly on Chess.com domains.
• Usage: Required solely to:
a) Detect the chessboard DOM element (`<chess-board>` or `<wc-chess-board>`).
b) Read the current piece layout and Board FEN notation to perform tactical analysis.
c) Render visual directional arrows, glowing square highlights, and the evaluation bar on the board.
d) Execute moves when Auto-Move is intentionally activated by the user.
• Scope: The extension is completely restricted to `https://www.chess.com/*`. It CANNOT run on or access any other domain (e.g. google.com, bank portals, email services, or other websites).
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4. ARE ALL THESE PERMISSIONS STRICTLY NECESSARY?
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YES. Each requested permission represents the absolute minimum necessary privilege required for the extension to fulfill its single purpose.
Here is why:
• Can the extension work without "storage"?
NO. Without the `storage` permission, every time you close your browser or navigate to a new page, all your custom engine settings (depth, delays, colors, auto-run toggles, HUD position) would reset to default. Local storage is indispensable for a functional user experience.
• Can the extension work without host permission for "https://www.chess.com/*"?
NO. By design, Chrome requires host permissions for content scripts to interact with a web page. Because Chess Vision Pro must inspect the chessboard and draw tactical arrows directly on the screen, host access to Chess.com is technically mandatory.
• Did we minimize our permissions to the utmost degree?
YES. Notice what we deliberately DO NOT request:
- NO `<all_urls>` permission: We do not request universal web access; we restrict access exclusively to Chess.com.
- NO "cookies" permission: We cannot read your session cookies or authentication tokens.
- NO "webRequest" or "declarativeNetRequest" permission: We do not intercept your network traffic.
- NO "identity" permission: We never request your Google or browser user identity.
- NO "tabs" permission: We do not monitor your active tabs or URL navigation history.
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5. DATA SECURITY & THIRD-PARTY SERVICES
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When using the optional Cloud Engine mode (Stockfish 18 via chess-api.com or Stockfish 17 via stockfish.online), the extension sends only the current anonymous board position (standard FEN string: e.g. "rnbqkbnr/pppppppp/8/8/4P3/8/PPPP1PPP/RNBQKBNR b KQkq e3 0 1") and requested search depth to receive engine evaluations. No IP logging, username, or identifying information is transmitted.
When using Local Stockfish mode, evaluation runs 100% offline via local Web Workers without initiating any outbound network connections.
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6. COMPLIANCE WITH CHROME WEB STORE POLICIES
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This extension strictly complies with:
• Google Chrome Web Store Developer Program Policies.
• Manifest V3 Security Guidelines (including the strict prohibition against remotely hosted code).
• The Single Purpose Policy.
• The Limited Use and User Data Policy.
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7. CONTACT & INQUIRIES
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If you have any questions or feedback regarding this Privacy Policy or the security of Chess Vision Pro, please visit our documentation website or reach out via the official Chrome Web Store support tab.