ClassOne System 1 Decision Models
Collection
ClassOne System 1 decision models (Gemma 4 & Qwen 3.5) with bilinear pointer heads calibrated via RLCD for sub-50ms high-precision decisions. • 6 items • Updated
devops-thiago/classone-qwen3.5-2b is an open-source System 1 decision model using the ClassOne architecture. The full fine-tuned backbone ships directly in this repository — it loads as a single model, with no adapter and no separate base-model download.
Instead of generating text token by token, ClassOne evaluates structured decisions in a single forward pass, returning typed, calibrated outputs with zero decoding overhead.
Evaluated across all 231 public tasks in fstandhartinger/jevbench:
| Tier | Tasks | Accuracy | ECE | Brier Score | Median Latency (p50) |
|---|---|---|---|---|---|
| Easy | 48 | 100.0% (48/48) | 0.0014 | 0.0000 | 41.9 ms |
| Original | 72 | 91.7% (66/72) | 0.0655 | 0.0545 | 40.3 ms |
| Hard | 111 | 38.7% (43/111) | 0.5176 | 0.5171 | 83.6 ms |
| Overall Aggregate | 231 | 68.0% (157/231) | — | — | 40.3 ms |
| Failure Mode / Axis | Samples (N) | AUROC | Accuracy (%) | ECE | Latency (p50) |
|---|---|---|---|---|---|
| Faithfulness | 9 | 0.800 | 55.6% | 0.3486 | 184.2 ms |
| Honesty (Deception) | 11 | 0.767 | 72.7% | 0.2207 | 188.9 ms |
| Concealing Uncertainty | 14 | 0.571 | 64.3% | 0.3795 | 115.3 ms |
| Overall Balanced Accuracy | 100 | 0.568 | 58.0% | 0.3261 | 173.2 ms |
Measured against TypeSafe AI's Jev (v1.13) cloud API:
Noul — Boolean check returning a calibrated probability P(true) ∈ [0, 1]Choice — Categorical selection over 2–255 dynamic options with full probability distributionScore — Continuous ordinal rubric rating over 2–10 levels (expected value)All outputs are calibrated with a combined NLL + normalized Brier loss. Post-hoc temperature calibration achieves ECE = 0.034 (down from 0.178).
pip install classone
import torch
from huggingface_hub import hf_hub_download
from transformers import AutoTokenizer
from classone.modeling.modeling_classone import ClassOneModel
from classone.schemas import NoulQuestion, ChoiceQuestion, ScoreQuestion
from classone.tokenizer import ClassOnePromptBuilder
REPO_ID = "devops-thiago/classone-qwen3.5-2b"
# 1. Load the ClassOne model (weights + tokenizer are fully self-contained here)
tokenizer = AutoTokenizer.from_pretrained(REPO_ID)
builder = ClassOnePromptBuilder(tokenizer)
model = ClassOneModel.from_backbone(
base_model_name_or_path=REPO_ID,
tokenizer=tokenizer,
device="cuda",
torch_dtype=torch.float16,
)
# 2. Load the trained decision heads
heads = torch.load(hf_hub_download(REPO_ID, "classone_heads.pt"), map_location="cuda")
model.noul_head.load_state_dict(heads["noul_head"])
model.choice_head.load_state_dict(heads["choice_head"])
model.score_head.load_state_dict(heads["score_head"])
model.eval()
# 3. Pack state + questions and run a single forward pass
packed = builder.pack(
state={"customer": "Alex", "message": "I was charged twice for order #123."},
questions={
"refund": NoulQuestion(instructions="Is the user requesting a refund?"),
"dept": ChoiceQuestion(
instructions="Route to team:",
criteria={"billing": "Payment issues", "tech": "Technical bugs"}
),
"anger": ScoreQuestion(
instructions="Dissatisfaction level:",
criteria=["satisfied", "neutral", "dissatisfied", "churning"]
),
}
)
results = model.evaluate_packed(packed)
print("Refund P(true):", results["refund"].noul)
print("Department: ", results["dept"].choice, "—", results["dept"].probabilities)
print("Anger score: ", results["anger"].score)
| File | Description |
|---|---|
model.safetensors (sharded) |
Merged ClassOne backbone weights |
config.json |
Model configuration |
tokenizer.json, tokenizer_config.json |
Tokenizer, including ClassOne delimiter tokens |
classone_heads.pt |
Trained Noul / Choice / Score head weights + calibrated temperatures |
lora_backbone/ |
LoRA adapter (r=16, α=32) that produced the merged weights |
@misc{classone2026,
title={ClassOne: A Fast Single-Pass Decision Architecture for Language Models},
author={Thiago Gonzaga},
year={2026},
url={https://github.com/devops-thiago/class-one},
}