@vibeleading/mcp-privacy-shield

The Privacy Shield — the Sanitization Gate, Tiered Sovereignty, and Privacy HUD. Keeps identity out of the AI's hands, keeps the Vault on-premise, and monitors a live Compliance Score.

Implements the Privacy Shield server from the appendix of Vibe Leading The AI.

What it does

• Sanitization Gate — replaces PII with tokens like [EMAIL_01] (or category masks like [EMAIL]). The AI understands the logic but never sees the identity.
• Tiered Sovereignty — classifies data into public / internal / restricted / vault zones. Restricted PII stays in the Vault on-premise; you bring the AI to the data, not the reverse.
• Privacy HUD — monitors a Compliance Score (0-100). Snap the connection if sensitive patterns start leaking into output.

Install

npm install -g @vibeleading/mcp-privacy-shield

Or run on demand with npx:

npx -y @vibeleading/mcp-privacy-shield
# or run straight from the GitHub source (builds automatically):
npx -y github:VibeLeading/mcp-privacy-shield

Requirements

• Node.js >= 22 — required. The server is ESM-only and uses modern Node built-ins. On older Node versions the process fails to start, which MCP clients report generically as "connection closed".
• No other runtime dependencies — everything ships with the package.

Client configuration

Add to your MCP client config (e.g. Claude Desktop, Cursor, or opencode):

{
  "mcpServers": {
    "privacy-shield": {
      "command": "npx",
      "args": ["-y", "@vibeleading/mcp-privacy-shield"]
    }
  }
}

Tools

| Tool | Arguments | Description | |------|-----------|-------------| | sanitize_text | text: string, mask?: boolean | Redact PII → tokens or masks. Returns redacted text, replacement map, triggered categories, and risk. | | classify_zone | text: string | Classify into public / internal / restricted / vault with confidence and reasons. | | compliance_check | text: string, required_zone?: string | Score 0-100, list violations, and report pass/fail. | | shield_catalog | — | List supported patterns and env config (no secrets exposed). |

Environment variables

| Variable | Default | Description | |----------|---------|-------------| | MCP_SHIELD_NAMES | 0 (off) | Set to 1 to enable capitalized-name pseudonymization ([PERSON_N]). High-confidence only, and off by default to avoid over-redaction. | | MCP_SHIELD_ACCOUNT_PATTERN | \b\d{8,17}\b | Regex used to detect bank/routing account numbers. |

Detected categories

• Emails, phone numbers, credit-card numbers, US SSNs, bank/routing account numbers, IPv4 addresses, URLs, and passport/ID patterns.
• Optionally, full personal names (two consecutive capitalized words) when MCP_SHIELD_NAMES=1.

What this does NOT do

This server is a gate, not a compliance guarantee. Specifically:

• It is heuristic/deterministic regex matching; it can miss novel or obfuscated PII and can produce false positives.
• No Luhn validation, no OCR, no cross-referencing against business records.
• It does not encrypt, store, or transmit anything, and it does not itself enforce legal compliance (GDPR, HIPAA, CCPA, etc.).
• Before relying on it for regulated data, pair it with a human-reviewed policy and a real data-loss-prevention layer.

Use it as one layer in a defense-in-depth strategy — not as a substitute for professional compliance review.

Publishing

Published to the npm registry via OIDC trusted publishing — no npm tokens stored anywhere. Pushing a version tag triggers the .github/workflows/publish.yml workflow:

npm version patch -m "release: v%s"
git push origin main --follow-tags

• One-time bootstrap. The very first published version cannot use trusted publishing (the trust relationship attaches to an existing package). Publish 0.1.1 once manually (npm publish after npm login, or a short-lived publish-scoped token), then configure Trusted Publisher on npmjs.com → the package → Settings → Trusted publishing → GitHub Actions → owner VibeLeading, repo mcp-privacy-shield, workflow publish.yml, action allow npm publish (requires 2FA once per package).
• Requires Node.js >= 22 and npm >= 11.5.1 on the runner (handled by the workflow).

License & Attribution

MIT — Copyright (c) 2026 Jean Machuca (see LICENSE).

This server implements concepts from the book Vibe Leading The AI: The Corporate Race Against Machines by Jean Machuca (ISBN 9798252505008, © 2026 Jean Machuca). The book is copyrighted commercial material; this repository does not republish its text. Buy the book at https://vibeleading.org or https://a.co/d/04L5YatK. Author website: jeanmachuca.com · Support on GitHub Sponsors: github.com/sponsors/jeanmachuca. See NOTICE.