Turn emails, invoices and contracts into clean fields

Where extraction usually starts

Most teams extract fields by asking a frontier model to “return valid JSON”, then add retries for answers that don’t parse and checks for fields that go missing. Every document pays frontier prices. A specialist returns your fields, in your shape, on every call.

How it works

1. Describe the job. List the fields and paste a few real documents as text: “From each invoice, return vendor, invoice number, total and due date.”
2. Agree on what good looks like. Facet writes plain statements of a good answer, like “totals are numbers without currency symbols” or “dates use year, month, day”, each with examples. Edit any that are off.
3. Create, then correct. Facet builds the specialist on its own, usually in about half an hour, and checks it against every statement before it goes live. When a field comes back wrong, say what should change. Facet quotes the fix before it spends anything.

Three ways to use it

• In the app: sign in, describe the fields, and choose Create.
• From your agent: connect Claude, Cursor, ChatGPT, Codex or VS Code to Facet, then paste:

Use Facet to build a specialist that reads invoice text and returns vendor, invoice
number, total and due date as JSON. Here are five real invoices: ... Show me the draft
and the price before you approve anything.

• In your code: keep your OpenAI SDK and change two lines, the address and the model name.

import os
from openai import OpenAI

client = OpenAI(base_url=os.environ["FACET_BASE_URL"], api_key=os.environ["FACET_API_KEY"])
reply = client.chat.completions.create(model="invoice-fields", messages=[{"role": "user", "content": invoice_text}])

Why a specialist for extraction

• The same shape every time. You define the fields once; every answer comes back in that shape, ready for your database.
• Checked before every update. A new version goes live only after it passes every statement you agreed on, and any update rolls back in one step.
• Fast and low cost. A Facet specialist does one job, so it answers faster than a frontier model, and every build shows its price before it starts.
• Yours. Export it any time, free, and run it wherever you like.