Redact PDF MCP server

An MCP server that permanently redacts PII from PDFs. Give an agent a PDF, get back a PDF with the sensitive text removed from the file — not covered with a black rectangle that anyone can select, copy, or delete.

Most "redaction" MCP servers scrub PII out of prompt text. This one takes a real document and returns a real redacted document.

claude mcp add redact-pdf -- npx -y redact-pdf-mcp

Then ask: "Redact the personal data in ~/Documents/contract.pdf".

Try it with no API key

The server ships a keyless tool, try_demo, so you can verify the whole path — client, server, API — before signing up for anything:

You: Use the redact-pdf server's try_demo tool.

Claude: The demo redacted a synthetic sample and removed 5 entities: Person (Jane Sample), Email (jane.sample@example.com), PhoneNumber (+1 415 555 0142), Organization (Globex Demo Inc.), Date (2026-03-14).

Same thing from a terminal, no install:

curl https://www.redact-pdf.ai/v1/demo

Related MCP server: Nutrient Document Engine MCP Server

What it does

• Permanent, irreversible redaction. The underlying text is deleted, not masked. It cannot be recovered by copy-paste, text extraction, or "remove object" in a PDF editor.

• PDFs and images. Pass a PDF, JPEG or PNG. Photos and screenshots do not need converting first; the output is a redacted PDF either way.

• Scanned documents. OCR handles image-only PDFs and photos of documents.

• 100+ languages for entity detection.

• Eight entity types: Person, Email, PhoneNumber, Address, Organization, Date, IBAN, CreditCard — plus your own always-redact and never-redact term lists.

• EU/Swiss processing.

• Human review when it matters. retention: "studio" keeps the detected masks so a person can check and adjust them before export.

Install

Claude Code

claude mcp add redact-pdf --env REDACT_PDF_API_KEY=your_key -- npx -y redact-pdf-mcp

Claude Desktop

claude_desktop_config.json:

{
  "mcpServers": {
    "redact-pdf": {
      "command": "npx",
      "args": ["-y", "redact-pdf-mcp"],
      "env": { "REDACT_PDF_API_KEY": "your_key" }
    }
  }
}

Cursor

.cursor/mcp.json:

{
  "mcpServers": {
    "redact-pdf": {
      "command": "npx",
      "args": ["-y", "redact-pdf-mcp"],
      "env": { "REDACT_PDF_API_KEY": "your_key" }
    }
  }
}

VS Code

code --add-mcp '{"name":"redact-pdf","command":"npx","args":["-y","redact-pdf-mcp"],"env":{"REDACT_PDF_API_KEY":"your_key"}}'

Get an API key at redact-pdf.ai/sign-up. Without one, try_demo still works; everything else will tell the agent to ask you for a key.

Tools

Redaction rules, on either redact tool:

Remote server

The package also ships a streamable-HTTP server for hosted use, where the API key travels per request instead of in the environment:

npx redact-pdf-mcp-http     # listens on :8080/mcp

POST /mcp
X-API-Key: your_key          (or: Authorization: Bearer your_key)

It is stateless — no sessions, no stored keys, nothing kept between requests — so each request gets its own short-lived server instance and one caller's key can never leak into another's tool call.

The handshake, tools/list, and try_demo work without a key, so a client can connect and verify the server before anyone signs up; every other tool returns 401 with a WWW-Authenticate challenge.

Documents are supplied as file_base64 (the remote server has no access to your filesystem).

Fetching a document by URL is off by default on the remote server. The address check is real — URLs resolving to loopback, private, or link-local addresses are refused, and every redirect hop is re-checked — but the socket resolves the hostname a second time after that check, so a DNS-rebinding attacker with a short TTL can still have the server validate one address and connect to another. Closing that requires pinning the connection to the validated address, which is not implemented yet, so an internet-reachable server does not offer the surface at all.

Set REDACT_PDF_ENABLE_URL_INPUT=1 to accept file_url, and only where you have your own egress controls (a network policy or allowlisting proxy) in front of the server. REDACT_PDF_ALLOW_PRIVATE_URLS=1 additionally permits private addresses, for a self-hosted instance fetching from internal storage.

stdio mode is unaffected: it runs on your own machine, where fetching a URL carries no privilege you do not already have.

Privacy

• No telemetry. The server makes exactly the API calls its tools describe, and nothing else. No analytics, no error reporting, no phone-home.

• Stateless. No database, no cache, no disk writes except the redacted PDF you asked for, at the path you asked for.

• Your originals stay yours. In stdio mode the input file is read and never modified. Under the default ephemeral retention the API deletes the original after processing.

• Idempotent by default. The idempotency key is derived from the file bytes and the redaction settings, so an agent that retries the same call gets the same job back instead of redacting — and billing — twice. That cache lasts 24 hours; pass an explicit idempotency_key when you genuinely want a second, separate redaction of the same file.

• Never overwrites. In stdio mode the redacted PDF is written atomically and the tool refuses to clobber an existing file.

Limits

• 50 MB per PDF, 10 MB per image, 100 files per job.

• PDF, JPEG and PNG in; always a PDF out. Convert other formats (DOCX, TIFF, HEIC) to PDF first.

• On the remote server, base64 inflates a document by about a third, so prefer file_url for anything large.

• Passing an empty pii_categories list is rejected: to the API an empty list means "redact nothing", which would return an untouched file reported as redacted. Omit the argument to use your account defaults.

• Billed per page against your plan quota and credit packs. A quota_exceeded error means top up — the tools tell the agent not to retry it.

Development

npm install
npm run build
npm test                 # offline unit + tool tests
npm run test:integration # hits the live keyless demo endpoint; no key needed

Links

• API docs: redact-pdf.ai/developers

• OpenAPI spec: redact-pdf.ai/openapi.yaml

• LLM index: redact-pdf.ai/llms.txt

Support questions about redaction quality, billing, or your account go to info@redact-pdf.ai — GitHub issues here are for the MCP server itself.

MIT licensed.