An open Jev-style decision model by Andy Zhang: a LoRA adapter on Gemma 4 26B-A4B (also on Gemma 4 12B) that reads a state and returns a temperature-calibrated probability for every option of a yes/no, choice or score question in one forward pass.
Ultra-small English encoders (17M, 68M and 395M) fine-tuned from Ettin rerankers. Each answers choice, noul and score questions with a probability per candidate and no generated text. Experimental v0 by one developer; the weights have no licence assigned yet.
Decides
choice, score, noul
choice, noul, score
Architecture
ajev
bekko
Fine-tuned from
google/gemma-4-26b-a4b-it
cross-encoder/ettin-reranker-400m-v1
License
apache-2.0
Unassigned: the weights licence is not finalised (treated as non-commercial); training code MIT
Availability
Open weights
Open weights
Hosted by
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Input price
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Decision accuracy
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Calibration error
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Valid action rate
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Median latency
49 ms
5 ms
p95 latency
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 ajev and bekko-system-one?
ajev is from Andy Zhang and bekko-system-one from Yuichi Tateno (hotchpotch). Both have open weights you can download and run. Both answer choice, score and noul questions. bekko-system-one is the smaller model, at 395M parameters to 26B. ajev is licensed apache-2.0; bekko-system-one, other.
Which is more accurate, ajev or bekko-system-one?
Neither publishes an accuracy figure. Test both on your own labelled examples.
Which is cheaper, ajev or bekko-system-one?
ajev: Free (open weights). bekko-system-one: Free (open weights). Open weights cost nothing per call beyond your own hardware.
Which is faster, ajev or bekko-system-one?
By their publishers’ figures, bekko-system-one answers in about 5 ms at the median and ajev in about 49 ms — measured on different hardware, so treat it as a rough guide.
Can I run ajev or bekko-system-one locally?
Yes, both: systemone pull andy-zhang/ajev and systemone pull hotchpotch/bekko-system-one download the weights.
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5.4 ms
Evaluation suite
Sequential requests, the maker's own measurement
The maker's short-input speed probe (4-option Choice, RTX 5090, 1 Oct 2026)
