Finest vs Not Diamond
Last updated 2026-08-19
Not Diamond is a routing intelligence API: you call it with a query, it recommends the model likely to perform best, and your code then makes the call, optionally with routers trained on your own evaluation data. Finest is a serving gateway with the decision inside: requests flow through it unchanged, substitutions happen only under sealed published evidence for the task class, everything else serves your requested model verbatim, and the fee is 25% of savings proven per request. One hands you better judgment. The other is accountable for the outcome.
| At a glance | Finest | Not Diamond |
|---|---|---|
| What it is | Gateway that serves and proves | Routing recommendation API |
| Integration | Base URL and key on existing clients | SDK call before each model call |
| Decision basis | Sealed evidence per task class, published | Trained routers, optionally on your evals |
| Fee model | No model markup. 25% of proven savings per request. No saving, no fee. | Platform pricing |
| Unproven traffic | Requested model, verbatim | Recommendation still returned |
| Proof of value | A receipt per request: model served, evidence, saving. | Your own downstream measurement |
Choose Finest when
- You want the optimization deployed by swapping a base URL, not by threading a second API through call sites.
- You want serving, evidence, and billing in one accountable loop with receipts.
- You want zero-risk defaults: unproven traffic runs exactly as written.
Choose Not Diamond when
- You want to keep serving fully in your own code and consume routing as advice.
- You have rich internal evals and want routers trained specifically on them.
- You are researching routing itself and want the decision exposed, not managed.
Advice APIs leave the hard part with you
A recommendation API improves a decision you still own. You integrate it at every call site, act on its answer, measure whether it helped, and explain regressions yourself. For teams that want routing as a component, that is the point.
Finest is for teams that want routing as a result. The gateway makes the decision under published evidence, serves the request, escalates when a cheaper arm refuses or fails validation, writes the receipt, and bills only from the saving it just proved. The integration cost is a base URL, and the accountability sits with the vendor.
Where your evaluation data fits
Not Diamond's strongest story is custom routers trained on your evaluation data. Finest's equivalent is the evidence bar: measurement on task classes with pre-registered thresholds, sealed corpora, and published records that authorize serving. Both take evaluation seriously. The difference is whether its output is advice returned to your code or authority exercised on your traffic with a receipt.
Questions people ask
- Can I use Not Diamond style recommendations with Finest?
- You can keep any advisory layer you like. Whatever model your code finally requests, Finest treats as the contract: served verbatim, or bettered only under published evidence.
- Which is less work to adopt?
- Finest is a base URL and key on OpenAI-shaped or Anthropic-shaped clients. A recommendation API is code at each decision point plus your own measurement of whether it paid off.
- Who measures whether the routing helped?
- With an advice API, you do. With Finest, the receipt does: requested model, served configuration, evidence, and the saving, verifiable per request.
In 2 minutes, start cutting your API spend without sacrificing quality. Free if you don’t save money.
No model markup. You pay the host’s rate. 25% of what it proves it saved on a request. No saving, no fee.