What it does
You send a state (text or a chat) and up to 64 typed questions: yes/no, choose one of k, or score on a rubric. The model
answers every question with a probability distribution over its options:
- one forward pass per question, with no generated text;
- the output is the probability of each option's label token;
- existing Jev clients only need a new base URL.
Table | |
|---|
| Base model | Qwen/Qwen3.5-4B (Apache-2.0) |
| Training | LoRA SFT (rank 32, alpha 64) on the language model, one epoch over about 713k rows. This release is step 5,650 of 5,655, the lowest validation loss. |
| Release format | LoRA merged into the base; bf16 weights. The vision tower and MTP head are unchanged. |
| Languages | English, Simplified Chinese, Traditional Chinese |
Quickstart
pip install "sglang==0.5.21" "transformers==5.12.1" requestsbash serve_knowline.sh PelaAI/KnowLine-4B-Gen1 0 8080 # SGLang (FP8 at load) on :9080 + /v1/systemone on :8080curl -s http://127.0.0.1:8080/v1/systemone -H 'Content-Type: application/json' -d '{ "model": "m", "state": "Customer: my order arrived broken, I want my money back.", "questions": {"refund": {"type": "noul", "instructions": "Should the agent offer a refund?"}, "tone": {"type": "choice", "instructions": "Customer tone?", "criteria": {"angry": "Angry", "neutral": "Neutral", "happy": "Happy"}}}}'
- Without SGLang:
python knowline_server.py --model PelaAI/KnowLine-4B-Gen1 --backend hf --port 8080 uses
transformers only. It is slower and runs bf16.
- Front end:
knowline_server.py is a single file and needs only transformers and requests.
- Full settings: the exact settings of our Decision Index runs are in INFERENCE.md.
Comparison
Decision Index 0.3, public suite. The full 0.3 score adds private tests that only the maintainers run (0.5 same-skill,
0.3 new-domain); ours is not available yet.
Table with columns: model, size, DI 0.3 public, DI 0.3 full, source| model | size | DI 0.3 public | DI 0.3 full | source |
|---|
| KnowLine-4B-Gen1 | 4B | 60.47 | not yet scored | self-run, official kit |
| Clef | 27B | 61.71 | 53.08 | board |
| Jev 1.13 | (API) | 57.96 | 60.11 | board |
Our public-suite scores by area:
Table with columns: area, KnowLine-4B-Gen1 (0.3 public), Jev 1.13 (0.2.1)| area | KnowLine-4B-Gen1 (0.3 public) | Jev 1.13 (0.2.1) |
|---|
| Knowledge & reasoning | 37.7 | 51.4 |
| Language | 60.8 | 62.0 |
| Retrieval & routing | 70.9 | 55.4 |
| Tools & agents | 86.8 | 75.1 |
| Arts & taste | 49.5 | 37.7 |
Releases
The model is trained in a self-evolving loop, and new versions will follow.
Table with columns: model, date, DI 0.3 public, DI 0.2.1, golden held-out (en / zh-Hans / zh-Hant), notes| model | date | DI 0.3 public | DI 0.2.1 | golden held-out (en / zh-Hans / zh-Hant) | notes |
|---|
| KnowLine-4B-Gen4 | 2026-10-10 | 64.90 | — | 69.7 / 70.1 / 65.1 | fourth release |
| KnowLine-4B-Gen3 | 2026-10-09 | 63.11 | — |
Evaluation
All results are self-run and not verified by a third party.
Held-out and Chinese evaluations
Table with columns: suite, accuracy| suite | accuracy |
|---|
| In-house evaluation set, English | 68.7 |
| In-house evaluation set, Simplified Chinese | 69.9 |
| In-house evaluation set, Traditional Chinese | 64.1 |
| C-Eval (4 categories, macro) | 77.9 |
| Open-Jev 1.1 test / OOD | 87.4 / 86.6 |
Web operation (Mind2Web official test splits, evaluation only)
Table with columns: split, element selection, operation (balanced)| split | element selection | operation (balanced) |
|---|
| test_task (websites seen in training, new tasks) | 93.1 | 96.6 |
| test_website (new websites) | 90.7 | 96.5 |
| test_domain (new domains) | 91.5 | 98.5 |
- So far this is only used to explore the model in RPA-style automation and to check that it generalises to some degree.
- The task is to pick the target element among it and up to 5 other candidates sampled from the page. This is easier
than the original Mind2Web protocol, so do not compare it with the Mind2Web leaderboard.
Game harness (KOF '98)
- Setup: single-bout character-mirror round robin, 11 players, 18 games per pair (990 games), argmax actions.
- Result: win rate 0.883 [0.83, 0.92], Elo 1910, tied for first of 11 with another internal checkpoint.
- Head-to-head: 17-0-1 against Jev 1.13, 15-3 against StartLux-Decision-4B, 18-0 against Clef-Flash.
- Caveat: the policy relies heavily on one move, a 623C anti-air uppercut used about 55% of the time. This is a
measured result in this harness, not general fighting-game skill.
Disclosures
- Decision Index training data: about 25% of the data is in Decision Index format, that is, synthetic items written
in the benchmarks' request formats. No Decision Index test item is included.
- Decontamination:
- Every component text (state, instructions, option texts) was checked against every Decision Index row and all of
our evaluation sets.
- Rows that are identical, or share any run of 50 consecutive characters, were removed.
- Game data: labels come from simulator rollouts or engines. Seeds and start states are disjoint from the evaluation
states.
- No model outputs as labels: no output of Jev or any other decision model was used as a training label.
- Teacher-labelled synthetic data: LLM teachers wrote and labelled our synthetic tasks. The labels were filtered, but
not all were checked by a human.
Limitations
- Knowledge-heavy reasoning: weaker than larger models. The knowledge area is 37.7 (0.3); MMLU-Pro, GPQA and HLE are
close to the base model.
- Math: answered without reasoning. The rebuilt 0.3 GSM8K scores 29.5.
- Prompt injection: an instruction planted in the state changes the answer about 9% of the time on our injection
set. Keep untrusted text clearly delimited.
- Calibration: ECE is about 0.05-0.06 on choice and yes/no questions and about 0.12 on score questions. For score
questions, fit a temperature on your own data. On the Decision Index 0.3 public suite, computed the board's way, ECE
is about 0.08-0.09 and 3.3% of answers are wrong at ≥95% confidence (board median 1.3%): the model is overconfident
overall.
- Private tests: part of our public-suite advantage comes from adapting to the question formats, so the 0.3 private
tests may score lower.
Citation
@misc{knowline4bgen1, title = {KnowLine-4B-Gen1: a 4B decision model}, author = {PelaAI}, year = {2026}, url = {https://huggingface.co/PelaAI/KnowLine-4B-Gen1}}
License
- Weights: Apache-2.0, the same as the base model.
- Code:
knowline_server.py is MIT (see the file header).