1/ Introducing CUA-S1: a family of System One Models, small, specialized, and built for computer use. Today we're open-sourcing CUA-S1-FORMS, the first in the family: github.com/trycua/cua
reflex
An open re-creation of Jev's decision model on an open-weights Qwen3.5-4B: it answers a list of typed questions in one forward pass over POST /v1/systemone in about 200 ms, never writing free text.
- Category
- Practices & Patterns
- Published by
- Community
- Author
- kshetrajna12
- Added
- 2026-09-22
Tagscommunitypythonopen-modelsbenchmarkscalibration
Highlights
- On public JevBench items it reports 1.000 easy, 0.917 standard, and 0.685 hard accuracy with hard-tier ECE 0.081 at about 200 ms.
- A frozen Qwen3.8-27B configuration reaches 0.958 standard, 0.766 hard, and ECE 0.061, at about 1 s per request.
- Official JevBench v1.2 placed the 4B configuration #5 of 36; fine-tuning in every form tried is reported not to help.
- What helped was the readout: lettered yes/no answers, Evidence/Criterion framing, and averaging two distinct option orders.
- A WebGPU browser demo runs a 650 MB Qwen3.5-0.8B locally in Chrome, Edge, or Safari 18+, uploading nothing.
Quickstart
bash
git clone https://github.com/kshetrajna12/reflex
cd reflex
git checkout stable
uv sync
uv run python examples/support_ticket.pyWatch out
MIT-licensed (Qwen weights keep Apache-2.0); needs a Linux machine with an NVIDIA GPU (8 GB for the default model), Python 3.12, and uv, and is not affiliated with TypeSafe.
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