Privacy Mask

Detect and mask sensitive information in images locally before they leave your machine.

Prerequisites

This skill requires the

privacy-mask

CLI to be pre-installed on the system. If it is not available, inform the user that they need to install it first:

1. Install via pip:

   pip install privacy-mask

2. Ensure Tesseract OCR is installed:

   brew install tesseract

   (macOS) or

   apt install tesseract-ocr

   (Linux)
3. Verify installation:

   privacy-mask --version

4. (Optional) Install NER support:

   pip install privacy-mask[ner]

When to use

• User sends a screenshot or image file (

  .png

  ,

  .jpg

  ,

  .jpeg

  ,

  .bmp

  ,

  .tiff

  ) that may contain private data
• User mentions privacy, masking, redacting, or anonymizing
• You need to analyze an image but want to redact sensitive info first
• IF the user shares a screenshot for debugging, THEN run

  privacy-mask mask <path> --dry-run

  first to check for PII
• IF detections are found, THEN mask the image before proceeding with analysis

Usage

Mask an image:

privacy-mask mask /path/to/screenshot.png
privacy-mask mask /path/to/screenshot.png --in-place
privacy-mask mask /path/to/screenshot.png --dry-run   # detect only, no masking
privacy-mask mask /path/to/screenshot.png --detection-engine regex  # regex only, skip NER
privacy-mask mask /path/to/screenshot.png --config /path/to/custom-config.json

Output is JSON:

{
  "status": "success",
  "detections": [{"label": "PHONE_CN", "text": "***", "bbox": [10, 20, 100, 30]}],
  "summary": "Masked 1 regions: 1 PHONE_CN"
}

Example workflow

1. User provides a screenshot:

   ~/Desktop/error-screenshot.png

2. Run detection:

   privacy-mask mask ~/Desktop/error-screenshot.png --dry-run

3. IF detections found, mask the image:

   privacy-mask mask ~/Desktop/error-screenshot.png

4. The masked output is saved as

   ~/Desktop/error-screenshot_masked.png

5. Use the masked image for further analysis

What it detects

• IDs: Chinese ID card, passport, HK/TW ID, US SSN, UK NINO, Canadian SIN, Indian Aadhaar/PAN, Korean RRN, Singapore NRIC, Malaysian IC
• Phone: Chinese mobile/landline, US phone, international (+prefix)
• Financial: Bank card, Amex, IBAN, SWIFT/BIC
• Developer keys: AWS, GitHub, Slack, Google, Stripe tokens, JWT, connection strings, API keys, SSH/PEM keys
• Crypto: Bitcoin, Ethereum wallet addresses
• Other: Email, birthday, IP/IPv6, MAC, UUID, license plate, MRZ, URL auth tokens
• NER (optional): Person names, street addresses, organizations, dates of birth, medical conditions

Constraints

• Do NOT send unmasked images to any external API or cloud service
• Do NOT skip masking when detections are found — always mask before sharing
• Do NOT modify the original image unless

  --in-place

  is explicitly requested
• Avoid running on very large images (>10MB) without warning the user about processing time

Anti-patterns

• Don't assume images are safe — always run detection even if the image "looks clean"
• Don't use

  --in-place

  by default — preserve the original unless the user asks otherwise
• Don't ignore dry-run results — if

  --dry-run

  finds PII, the image must be masked before use
• Don't hardcode config paths — use the bundled default or let the user specify

  --config

Important

• All processing is local and offline — no data leaves the machine
• Configure rules in the bundled

  config.json

  or pass

  --config

  for custom rules