# DecisionTune: decisiontune

> DecisionTune's 395M decision model: ModernBERT-large fine-tuned with a 4 KB scoring head that scores a marker per option, answering a choice or yes/no question in one encoder pass with a probability for every option. Runs locally on CPU or GPU via PyTorch, MLX or ONNX.

- Page: https://systemonemodels.ai/decision-tune/decisiontune
- API: https://api.systemonemodels.ai/v1/models/decision-tune/decisiontune
- Download: `pip install systemonemodels && systemone pull decision-tune/decisiontune`

## Facts

| | |
|---|---|
| Maker | DecisionTune (https://systemonemodels.ai/decision-tune) |
| Decides | choice, noul, route, classify |
| Architecture | decisiontune |
| Base model | answerdotai/modernbert-large |
| Parameters | 395M |
| Context | 8K tokens |
| Licence | apache-2.0 |
| Availability | Open weights |
| Released | 2026-10-04 |
| Latest version | 1.0.0 |

## Model card

<!-- generated by scripts/seed_catalog.py; edit content/models/catalog.yaml -->

# DecisionTune 1.0

DecisionTune's 395M decision model: ModernBERT-large fine-tuned with a 4 KB scoring head that scores a marker per option, answering a choice or yes/no question in one encoder pass with a probability for every option. Runs locally on CPU or GPU via PyTorch, MLX or ONNX.

Probabilities are a plain softmax, not calibrated, as the card says. English only; results depend on option order and how options are described. Distilled with soft labels from Cloudflare's Clef-flash. The maker's own runs of the third-party Decision Index give 29.57 on 0.2.1 (a second seed 29.13), with low Knowledge and Arts scores; the maker ran the index several times during development and designed fixes after seeing results, though no index rows were used for training. The decision-tune package offers a local /decide server, an MCP server and spreadsheet recipes. Inputs over 8,192 tokens are refused, not truncated.

## What it decides

- **choice** — picks one option from a set
- **noul** — answers a yes/no question with one probability
- **route** — sends the input to one of several destinations
- **classify** — assigns a category from a fixed taxonomy

## At a glance

| | |
|---|---|
| Parameters | 395M |
| Base model | `answerdotai/ModernBERT-large` |
| Maker | DecisionTune |
| Released | 2026-10-04 |
| License | apache-2.0 |

## Get the weights

```bash
pip install systemonemodels
systemone pull decision-tune/decisiontune
```

The files are served from the maker's Hugging Face repository, [`decision-tune/decisiontune-1.0`](https://huggingface.co/decision-tune/decisiontune-1.0), and verified against the checksums recorded here.

## Read more

- [Model card](https://huggingface.co/decision-tune/decisiontune-1.0)
- [Code](https://github.com/decision-tune/decision-tune)
- [Site](https://decisiontune.com)

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

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From System One Models — https://systemonemodels.ai/ · every System One model: https://systemonemodels.ai/system-one-models