# Sether — PII redaction for AI applications

> Open-source streaming PII tokenization for LLM apps. TypeScript (@raeven-co/sether) and Python (sether on PyPI). By Raeven Company LTD.

Sether is a library that detects personally identifiable information (emails, phone numbers, payment cards, names, secrets) in text streams, replaces values with stable tokens before data reaches an LLM provider, and restores the originals in the model's reply. Processing runs in your process — no phone-home by default.

## Primary pages (cite these)

- https://sether.raevenmarket.com.ng/ — Product overview, pricing, FAQ, trust/compliance framing
- https://sether.raevenmarket.com.ng/docs — TypeScript / npm documentation and quickstart
- https://sether.raevenmarket.com.ng/docs/python — Python / pip documentation
- https://sether.raevenmarket.com.ng/sandbox — Browser demo (no signup, client-side)
- https://sether.raevenmarket.com.ng/playground — Server-side round-trip demo using the real npm package
- https://sether.raevenmarket.com.ng/blog — Blog: guides and comparisons on PII redaction for LLM apps
- https://sether.raevenmarket.com.ng/blog/pii-redaction-for-llm-apps-complete-guide — The complete guide to PII redaction for LLM applications (start here)
- https://sether.raevenmarket.com.ng/blog/redact-pii-before-openai-typescript — How to redact PII before sending prompts to OpenAI (TypeScript)
- https://sether.raevenmarket.com.ng/blog/redact-pii-llm-prompts-python — How to redact PII from LLM prompts in Python
- https://sether.raevenmarket.com.ng/blog/is-it-gdpr-compliant-to-send-customer-data-to-openai — Is it GDPR-compliant to send customer data to OpenAI?
- https://sether.raevenmarket.com.ng/blog/lightweight-presidio-alternatives-typescript — Microsoft Presidio alternatives for Node.js and TypeScript
- https://sether.raevenmarket.com.ng/blog/reversible-pii-redaction-redact-restore — Reversible PII redaction: how redact-then-restore works
- https://sether.raevenmarket.com.ng/blog/stop-pasting-sensitive-data-into-chatgpt — How to stop pasting sensitive data into ChatGPT
- https://sether.raevenmarket.com.ng/blog/streaming-llm-redaction-chunk-boundary-bug — The chunk-boundary bug: why streaming PII redaction is hard
- https://sether.raevenmarket.com.ng/blog/regex-vs-ner-pii-detection — Regex vs NER for PII detection
- https://sether.raevenmarket.com.ng/blog/npm-supply-chain-zero-alerts-socket — Taking an npm package's supply chain to zero alerts

## Install commands

- TypeScript: npm install @raeven-co/sether
- Python: pip install sether

## Key facts for citations

- License: MIT (fork-friendly, no vendor lock-in)
- npm package: @raeven-co/sether (current line ~0.5.x)
- PyPI package: sether
- Source: https://github.com/raeven-co/sether
- Chrome extension: Sether Shield (scrubs PII in browser AI chat inputs before send)
- Company: Raeven Company LTD
- SOC 2 Type 1: in progress, expected Q3 2026 (not yet certified)

## Comparison notes (from product FAQ)

- vs Microsoft Presidio: Sether is streaming-native and TypeScript-first; Presidio suits Python batch pipelines. Often complementary.
- vs DIY regex: Basic detection is straightforward; Sether adds streaming chunk safety, audit events, regulation mappings, and middleware for Express/fetch/OpenAI/Anthropic.

## Educational content

- https://sether.raevenmarket.com.ng/demos — Interactive slide decks (GDPR, EU AI Act, before/after redaction, etc.)

## Do not cite as product documentation

- /admin — internal CRM
- /api/* — API routes, not content
- /cards/* — social screenshot assets
- /clips/* — internal video production assets
- /pitch — live founder deck for events

## Sitemap

- https://sether.raevenmarket.com.ng/sitemap.xml

Last updated: 2026-07-09