# Cua: cua-s1-forms

> A 2.8 MB byte-level transformer for GUI form filling. For each form element it returns one probability per typed option (fill an entity, check, click or skip), using jevlike's option-attention head.

- Page: https://systemonemodels.ai/cua/cua-s1-forms
- API: https://api.systemonemodels.ai/v1/models/cua/cua-s1-forms
- Download: `pip install systemonemodels && systemone pull cua/cua-s1-forms`

## Facts

| | |
|---|---|
| Maker | Cua (https://systemonemodels.ai/cua) |
| Decides | choice |
| Architecture | cua-s1 |
| Parameters | 706K |
| Licence | mit |
| Availability | Open weights |
| Released | 2026-09-18 |
| Latest version | 2026.09 |

## Reported evaluation

Suite: 196-decision evaluation on real forms. Numbers are the publisher's own.

- Decision accuracy: 100.0%

## Model card

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# cua-s1-forms

A 2.8 MB byte-level transformer for GUI form filling. For each form element it returns one probability per typed option (fill an entity, check, click or skip), using jevlike's option-attention head.

Trained on 10,000 synthetic episodes, it scores 100% on a 196-decision evaluation of real forms against 83.6% for hosted Jev on the same task, and is explicitly not RLCD-calibrated. Siblings in the same organisation: cua-s1-4b-0.2 (an Apache-2.0 LoRA on Qwen3.5-4B, text and multimodal adapters), and cua-s1-4b-0.1 and cua-s1-nano-0.1, which carry no licence.

## What it decides

- **choice** — picks one option from a set

## At a glance

| | |
|---|---|
| Parameters | 706K |
| Maker | Cua |
| Released | 2026-09-18 |
| License | mit |
| Reported accuracy | 100.0% |

## Get the weights

```bash
pip install systemonemodels
systemone pull cua/cua-s1-forms
```

The files are served from the maker's Hugging Face repository, [`cua-ai/cua-s1-forms`](https://huggingface.co/cua-ai/cua-s1-forms), and verified against the checksums recorded here.

## Read more

- [Source](https://github.com/trycua/cua/tree/main/libs/cua-s1)
- [Weights on Hugging Face](https://huggingface.co/cua-ai/cua-s1-forms)

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*This page was opened by System One for Cua, who can claim the organisation and take it over at any time.*

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