How we built it

  • Two Nemotron models, two jobs. nvidia/nemotron-3-nano-30b-a3b is the cheap, fast writer. nvidia/nemotron-3-super-120b-a12b is the auditor, with the reasoning to catch an inconsistency. That's the "Nano/Super for fast calls… make your credits stretch" pattern Nebius recommends.
  • Token Factory's OpenAI-compatible API. Calls go to https://api.tokenfactory.nebius.com/v1 (nemotron.py). Model IDs are environment variables, so swapping models is a config change.
  • Measured cost and latency per explanation on Token Factory (10 synthetic claims, 2026-10-24; means, output includes reasoning tokens):
Model Role Tokens in/out Latency Cost
Nemotron 3 Nano writer 161 / 944 7.9 s $0.00024
Nemotron 3 Super auditor 254 / 204 1.9 s $0.00026
Total per explanation 9.8 s $0.00050

Design: one claim, one honest answer

The demo page (a replay of the recorded run) is for a patient or a billing-office agent:

  1. Pick a document. The EOB text with every evidence span highlighted; each extracted field links to its line.
  2. Conclusion card. Match, mismatch (stated vs recomputed amount, with the line) or the exact missing fields; no amount is guessed.
  3. Explanation and run cards. The patient text with badges (Nemotron or safe template, auditor verdict, guardrails), plus model IDs, tokens, latency and cost per call.

A billing-office agent can paste the explanation into a patient message with confidence. If the badge says template, the reason tells them what the model got wrong.

Trust by design

  • The model never computes money. Every amount comes from the deterministic ledger.
  • Two independent checks. One is a model-based audit (Nemotron Super) and one is rule-based (guardrails). Both must pass.
  • Fail closed. Malformed auditor JSON, a missing API key, an audit failure or an unsupported amount all lead to the safe template.
  • Transparent output. Each response reports source (nemotron or safe-template), the auditor's verdict and any guardrail violations, so staff can see why.

Accomplishments that we're proud of

Every conclusion shows where it came from. In a live run on Nebius Token Factory, a synthetic EOB goes in, Nemotron 3 Nano extracts each field with a verbatim quote, and code checks every quote against the document (line and character span), recomputes what the patient owes, and compares it with the amount the EOB states. 9/9 runs (3 documents × 3) reached the right outcome: a match at $551.00, a mismatch caught (the EOB says $601.00 on line 10; its own terms give $551.00), and an incomplete document that names exactly what's missing (coinsurance, out-of-pocket maximum) instead of guessing. Median 16.0 s and $0.00087 per document. It explains and flags; a person decides what to do.

8/8 offline tests with mocked Nemotron responses (5 pipeline, 3 document journey):

  • a correct draft is shown;
  • a draft that invents a $50 refund is caught by the guardrails (unsupported_amount:50.00) and replaced;
  • an auditor "not ok" leads to the template;
  • malformed auditor output leads to the template;
  • no model available leads to the template, with the correct $551 total.

Live run on Token Factory over 10 synthetic claims: 10 shown as Nemotron drafts, 0 fallbacks. Auditor stress test (30 calls: a correct text plus an inflated total and an invented $50.00 refund per claim): Nemotron Super flagged 20/20 injected errors and raised 1 false alarm in 10 correct texts (it objected to a line item omitted from the summary). The guardrails missed 1 of 20: a $50.00 "refund" on a claim where $50.00 is a real ledger amount. Super caught it, which is why both checks are required. Total spend for all live runs today: about $0.03.

What we learned

Arithmetic should never be the model's job, and the model's words should be checked before a patient sees them.

Built With

  • nebius-token-factory
  • nemotron-3-nano
  • nemotron-3-super
  • nvidia-nemotron
  • python
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