OpenAI Decisions API: What It Is, vs Jev and Laya
What the OpenAI Decisions API does, what OpenAI has and has not published, and how it compares with Jev, Liquid AI d1 and the open-source Laya.
The OpenAI Decisions API is a new OpenAI endpoint that picks one answer from a list you define instead of writing text. You send a question, a fixed set of candidate answers and some context (text or an image), and the OpenAI Decisions API returns the chosen answer. OpenAI announced it at DevDay on September 29, 2026, and runs it on a version of GPT-6 Luna, its low-cost model.
That puts OpenAI in the same category as TypeSafe's Jev, Liquid AI's d1 and the open-source Laya: System One models, which make fast, bounded decisions while a larger model does the slow reasoning. This page collects what OpenAI has published, what it has not, and how the OpenAI Decisions API compares with the System One models you can use today.
OpenAI Decisions API at a glance
| What OpenAI has said | |
|---|---|
| Announced | DevDay, September 29, 2026 |
| Model | a version of GPT-6 Luna |
| Input | a question, a list of predefined answers, and context as text or images |
| Output | one answer from your list, not generated text |
| Speed | 10x faster than GPT-6 Luna through the regular API: 150 ms against 1.6 s (OpenAI's figures) |
| Use cases | classify content, route requests, decide an agent's next step |
| Availability | limited preview for selected API customers; broad release announced for the coming days |
As of October 1, 2026, OpenAI has not published a price, the request and response format, the maximum number of answers per question, or whether the OpenAI Decisions API returns a probability for each option. The speed figures come from OpenAI and have not been measured independently.
How the OpenAI Decisions API differs from Jev and Laya
| OpenAI Decisions API | TypeSafe Jev | Liquid AI d1 | Laya | |
|---|---|---|---|---|
| Who runs it | OpenAI (hosted) | TypeSafe (hosted) | Liquid AI (hosted) | you, or a hosted Laya API |
| Weights | closed | closed | closed | open, Apache 2.0 |
| Input | text or images | text | text | text, including JSON |
| Question types | pick one answer | choice, score, noul | choice, score, noul | choice, score, noul |
| Probabilities per option | not published | yes, calibrated | yes, calibrated | yes |
| API format | not published | POST /v1/systemone | POST /v1/systemone (TypeSafe SDK works) | POST /v1/systemone |
| Price | not published | $0.042 per 1M input tokens | free tier; paid price not published | free to self-host |
| Speed | 150 ms (OpenAI's figure) | 410 ms median in our test, network included | not published | 11 to 54 ms locally in our test |
| Fine-tuning | not published | no | no | yes, on your own labels |
The biggest practical differences:
- Images. The OpenAI Decisions API takes images as context. Jev, d1 and Laya read text only.
- One wire format, or a new one. Jev, d1 and Laya all speak
POST /v1/systemone, so code moves between them by changing the base URL. The OpenAI Decisions API has its own interface, which OpenAI has not documented yet. - Probabilities. System One models return a calibrated probability for every option, which is what lets you act automatically above a threshold and send the rest to a human. OpenAI has only described the OpenAI Decisions API as returning a selection.
- Control. Laya's weights are open: you can run it on your own servers, keep data in-house and fine-tune it. The three hosted APIs, OpenAI included, cannot be self-hosted.
Which one should you use?
| Your situation | Start with |
|---|---|
| Decisions over screenshots, photos or other images | OpenAI Decisions API, once you have access |
| You already use OpenAI and want one bill and one account | OpenAI Decisions API |
| You need probabilities to set thresholds and route uncertain cases | Jev, d1 or Laya |
| You want a documented API today, with SDKs and per-token pricing | Jev |
| Data must stay on your servers, or you want to fine-tune | Laya, self-hosted |
| You want open weights without running servers | a hosted Laya API |
If you are evaluating now, build against the /v1/systemone format with Jev or Laya and keep your questions in one place. When OpenAI publishes the OpenAI Decisions API format, you can add it as one more backend and compare all of them on the same labelled sample. Our System One benchmark shows how much accuracy differs between models on identical questions.
Is the OpenAI Decisions API a Jev competitor?
Yes, for hosted use. Both target the same job: a fast, cheap decision inside an agent or a pipeline, so the expensive model is only called when it is needed. OpenAI has not said the launch is a response to Jev. For teams already on OpenAI, the Decisions API removes the need for a second provider; for teams that need calibrated probabilities, an open model or a documented API today, Jev and Laya still cover needs that OpenAI has not addressed yet.
FAQ
Is the OpenAI Decisions API available now?
Only as a limited preview for selected API customers. OpenAI announced broad availability for the coming days after DevDay on September 29, 2026.
How much does the OpenAI Decisions API cost?
OpenAI has not published a price. Do not assume regular GPT-6 Luna token rates: it is a separate endpoint and OpenAI said it will share details at broad release. For reference, Jev costs $0.042 per 1M input tokens and Laya is free to self-host.
Does the OpenAI Decisions API return probabilities?
OpenAI has described the output as the selected answer. Whether it also returns a probability for each option is not published. Jev, d1 and Laya return a probability for every option.
Can I use the TypeSafe SDK or Jev code with the OpenAI Decisions API?
Not as far as OpenAI has shown. Jev, Liquid AI d1 and Laya share the /v1/systemone format; the OpenAI Decisions API has its own interface, not yet documented.
Is there an open-source alternative to the OpenAI Decisions API?
Yes. Laya is an open-weight System One model under Apache 2.0, with a 100+ language checkpoint, and other open models are listed on System One models compared and Jev alternatives.
Sources
- The Decoder: OpenAI expands Codex and its API at DevDay
- Liquid AI decision models documentation
- TypeSafe: Introducing System One Models and Jev
Last verified: October 1, 2026. We will update this page when OpenAI publishes documentation and pricing.