Proof
We don’t ask you to trust us. We hand you the means to check.
Every trust claim Worthune makes resolves to an artifact you can open or a job you can watch run. This page is the index of all of them — and the definition of the method behind the mark.
Concordance testing
con·cor·dance — agreement between independent witnesses.
Every Worthune model is implemented twice: once in the engine that serves you, and a second time — separately, in a different language, from the published spec alone, with no access to the engine’s code. The two must agree on 250 cases per model, to one part in a billion, before any release. When they disagree, the release stops. The harness re-runs on every change.
Our mark is a picture of it: two squares drawn independently, solid only where they overlap. The answer is the shape they share, and nothing outside it.
What it does mean
- The engine implements its documented model exactly.
- The spec is precise enough for independent reproduction — that’s what the second implementation proves.
- Regressions are caught: the harness re-runs on every change, and a mismatch blocks the release.
What it does not mean
- That a model’s financial judgment is right for your situation — models simplify, and each spec names what it leaves out.
- That we’ve never shipped a mistake. We have; the fixes are in the public changelog. The method exists because we decided never to rely on trust again — ours included.
- Outputs are planning illustrations, not financial advice.
The artifacts
Six things you can open right now
Specs
A versioned contract per model
Inputs, valid domains, exact formulas, assumptions, and what the model deliberately leaves out. Three specs are published in full — the proof of the method; the full catalog's specs come with a subscription, and every model's input contract is public.
browse the catalog →Cases
Open test vectors
The exact 250 cases per model the Concordance harness runs — deterministic and re-runnable against your own integration. Three datasets are open downloads; the full set comes with a key. Not a sample of our testing; the testing itself.
download the datasets →Constants
A sourced facts registry
Every IRS limit, bracket, and SSA factor the models consume, with its primary source, effective period, and the date a human last checked it. We publish what we run.
open the registry →Changelog
No silent changes
Model behavior changes only through a spec version bump with a public changelog entry — including our own bug fixes, stated plainly. Pin a version and hold us to it in CI.
read the changelog →Records
A fingerprint in every response
Each run returns a SHA-256 record over the model, spec version, inputs, and outputs. Store it, recompute it months later, and prove where a number came from.
see the envelope →Usage
Even our traction is public
We ask you to trust our numbers, so ours are checkable: aggregate API usage, updated daily, honest zeros included.
GET /api/v1/telemetry →47 models in the catalog today. The maintenance posture, in writing: we maintain the registry and the models against primary sources on a best-efforts basis and version every change publicly — the artifacts above are how you hold us to it.