Proofetch MCP server

proofetch — verified extraction with proof per field

Structured data from PDFs and web pages, where every value is backed by an exact source quote — or honestly left null. Never guessed. Each result ships with a cryptographically signed receipt you can verify yourself.

proofetch is a hosted MCP server and HTTP API built for developers and AI agents. You pay only for fields that pass the proof — €0.02 per verified field. Empty or unprovable fields cost nothing.

• 🔗 Landing page & pricing: https://vektoris.de/proofetch
• 🤖 MCP endpoint (remote): https://proofetch-vektoris-ai-workflows.vercel.app/mcp
• 🧾 Listed in the official MCP registry: io.github.Vektoris-AI/proofetch

This repository is the public connector & documentation for the hosted proofetch service. The extraction pipeline itself is operated as a service — you don't self-host it, you call it with an API key.

Why proofetch

Normal extraction fills every field — even when the value is invented. You then have to re-check every number by hand. proofetch is different:

• Never guesses. Unsure? The field is null + flagged, instead of a fabricated value.
• Provenance per field. Every value comes with the exact source quote, verifiable against the original document.
• Signed receipt. The result is sealed in a signed receipt (Ed25519) — you, or an escrow, verify it without having to trust us.
• Pay for truth only. Billing is per field that passes the proof (verdict: PASS).

Get an API key

Buy prepaid balance (from €5) on the landing page — you get your key instantly after payment:

👉 https://vektoris.de/proofetch#preise

Quickstart — HTTP API

curl -X POST https://proofetch-vektoris-ai-workflows.vercel.app/extract \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "source": { "type": "pdf_url", "value": "https://example.com/invoice.pdf" },
    "targetSchema": {
      "type": "object",
      "properties": {
        "invoice_total": { "type": "string" },
        "due_date":      { "type": "string" },
        "invoice_number":{ "type": "string" }
      },
      "additionalProperties": false
    }
  }'

Source types (source.type): pdfurl, pdfbase64, url, text, html. targetSchema is a standard JSON Schema (type: "object", properties, additionalProperties: false).

What you get back

{
  "data": {
    "invoice_total": "1,190.00 EUR",
    "due_date": "2024-09-30",
    "invoice_number": null          // honest null — not found in source
  },
  "fields": [
    { "path": "invoice_total", "value": "1,190.00 EUR", "verdict": "PASS",
      "provenance": { "quote": "1,190.00 EUR", "start": 43, "end": 55 } },
    { "path": "invoice_number", "value": null, "verdict": "FAIL", "provenance": null }
  ],
  "verdict": "PARTIAL",
  "receipt": { "v": 1, "jobId": "pf_…", "outputHash": "sha256:…" },
  "billing": { "charged": true, "amountCents": 4 }
}

• data — clean JSON, each field proven or honestly null
• fields[] — per field: source quote (provenance) + verdict (PASS/FAIL)
• verdict — overall: PASS, PARTIAL, or FAIL
• receipt — signed proof with hashes, self-verifiable

Check your balance any time: GET /billing/balance with the same key.

Use as an MCP server (remote)

proofetch speaks the Model Context Protocol over Streamable HTTP. Point any MCP-capable client at the remote endpoint with your key as a bearer token.

Endpoint: https://proofetch-vektoris-ai-workflows.vercel.app/mcp Auth: Authorization: Bearer YOURAPIKEY Tool: verified_extract — same contract as the HTTP API above.

Example client config (generic MCP streamable-http remote):

Shortened. The full README is on GitHub.