OpenAI's decision endpoint, announced at DevDay 2026. It focuses GPT-6 Luna on developer-defined questions that have a finite set of predefined answers, with text or image context, for classification, routing and an agent's next action.
A Gemma 4 12B fine-tune for typed decisions that also chats and reads images. Ships as GGUF for llama.cpp, holds a 64K context on a 16 GB GPU, and serves /v1/systemone next to /v1/chat/completions.
Decides
choice, classify, route
choice, score, noul, classify, route
Architecture
gpt-6-luna
winnow
Fine-tuned from
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google/gemma-4-12b-it
License
proprietary
apache-2.0
Availability
Hosted API
Open weights
Hosted by
OpenAI
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Input price
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Decision accuracy
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85.7%
Calibration error
—
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Valid action rate
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Median latency
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143 ms
p95 latency
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Evaluation suite
Figures are from each model’s manifest; accuracy and latency are what the publishers report, on their own suites and hardware. Add a third model.
Questions
What is the difference between decisions-api and winnow?
decisions-api is from OpenAI and winnow from EldanRing. decisions-api is only available as a hosted API; winnow has open weights you can download and run. Both answer choice, classify and route questions. Only winnow answers score and noul. decisions-api is licensed proprietary; winnow, apache-2.0.
Which is more accurate, decisions-api or winnow?
Only winnow publishes an accuracy figure (85.7% on JevBench public subset (231 items), Q8_0); decisions-api does not, so there is no comparison to make without your own test.
Which is cheaper, decisions-api or winnow?
decisions-api: Hosted, price not published. winnow: Free (open weights). Open weights cost nothing per call beyond your own hardware.
Can I run decisions-api or winnow locally?
winnow yes — systemone pull eldanring/winnow downloads its weights. The other is only served as a hosted API.
