WaterSheep

Calibrated decisions for any text.

Website · Demo · Model

WaterSheep answers yes/no, single-choice, rating and multi-label questions about any text, with a probability for every option.

Usage

pip install transformers torch

from transformers import pipeline

ws = pipeline(model="samratduttaofficial/WaterSheep", trust_remote_code=True)
ws("I was charged twice.", question="Which team should handle this?", options=["billing", "shipping", "support"])

Type	Options	Answer
noul	none (yes/no)	probability of yes
choice	any labels	the best option
score	a digit scale, e.g. 1 to 5	the expected level
multi	any labels, with type="multi"	every option above the threshold

Every answer includes a probability for each option.

Using Jev?

WaterSheep is an open-source alternative to Jev. Run it as a local server:

pip install git+https://github.com/SamratDuttaOfficial/WaterSheep
watersheep --model samratduttaofficial/WaterSheep --serve

It answers Jev's POST /v1/systemone requests on your machine, and TypeSafe's Python SDK works against it without code changes:

export TYPESAFE_BASE_URL=http://127.0.0.1:8766

Any API key value works locally. Multi-label questions ("type": "multi") work too, as plain JSON. WaterSheep is independent and not affiliated with TypeSafe AI.

Download

hf download samratduttaofficial/WaterSheep --local-dir WaterSheep

Or with Git (requires Git LFS):

git clone https://huggingface.co/samratduttaofficial/WaterSheep

Then load it from the folder, offline:

ws = pipeline(model="WaterSheep", trust_remote_code=True)

API

Deploy it as a Hugging Face Inference Endpoint, then:

curl https://YOUR-ENDPOINT -H "Authorization: Bearer $HF_TOKEN" -H "Content-Type: application/json" -d '{"inputs": "I was charged twice.", "parameters": {"question": "Which team should handle this?", "options": ["billing", "shipping", "support"]}}'

JavaScript

No install; runs in the browser:

<script type="module">
  import { decide } from "https://samratduttaofficial.github.io/WaterSheep/watersheep.js";
  console.log(await decide("I was charged twice.", "Which team should handle this?", ["billing", "shipping", "support"]));
</script>

With a downloaded copy on your web server, call load({ base: "WaterSheep/" }) first.

Other languages: run onnx/model_quantized.onnx with ONNX Runtime; watersheep.js shows the input format.

Python package

pip install git+https://github.com/SamratDuttaOfficial/WaterSheep

from watersheep import WaterSheep

ws = WaterSheep.load("samratduttaofficial/WaterSheep")
ws.decide("I was charged twice.", "Which team should handle this?", ["billing", "shipping", "support"])

decide returns the answer, its confidence and a probability for every option. ask answers several questions about one text:

ws.ask({
    "state": {"customer": "Priya (premium plan)",
              "message": "Charged twice for order #4411 and the package is 12 days late."},
    "questions": {
        "escalate": {"type": "noul", "instructions": "Should a human agent take over now?"},
        "team": {"type": "choice", "instructions": "Which team should handle this?",
                 "criteria": {"billing": "payments, refunds", "shipping": "delivery problems"}},
        "frustration": {"type": "score", "instructions": "How frustrated is the customer?",
                        "criteria": ["calm", "annoyed", "frustrated", "furious"]},
        "issues": {"type": "multi", "instructions": "Which issues are reported?",
                   "criteria": ["double charge", "late delivery", "damaged item"]},
    },
})

Type	Question	Answer
noul	yes/no	probability of yes
choice	single choice	the option, with a probability for each
score	rating scale	the expected level, with a probability for each
multi	multi-label	every option above the threshold, with probabilities

Command line:

watersheep --model samratduttaofficial/WaterSheep --question "Which team should handle this?" --options billing,shipping,support --state "I was charged twice."

--serve runs a local HTTP API on port 8766.

Evaluation

Evaluation	Accuracy	ECE
In-distribution test split	77.8%	0.026
Held-out datasets, not seen in training	61.2%	0.043

ECE is the expected calibration error (lower is better).

Accuracy against confidence for each question type, before (raw) and after calibration.

Benchmarks

Benchmark	Suite	Questions	Accuracy	ECE	In training data
goemotions	sentiment	2000	22.4%	0.023	other split
hatecheck	safety	2000	75.1%	0.139	no
legal_abercrombie	legal	95	21.1%	0.316	no
legal_contract_nli_confidentiality_of_agreement	legal	82	69.5%	0.177	no
legal_corporate_lobbying	legal	490	68.4%	0.216	no
legal_cuad_audit_rights	legal	1216	86.3%	0.041	no
legal_definition_classification	legal	1337	56.9%	0.279	no
legal_function_of_decision_section	legal	367	24.3%	0.245	no
legal_hearsay	legal	94	56.4%	0.307	no
legal_overruling	legal	2000	62.5%	0.151	no
legal_personal_jurisdiction	legal	50	50.0%	0.160	no
legal_privacy_policy_qa	legal	2000	58.9%	0.274	no
legal_proa	legal	95	51.6%	0.379	no
legal_ucc_v_common_law	legal	94	62.8%	0.171	no
prompt_injection	safety	116	91.4%	0.079	other split
xstest	safety	450	73.6%	0.140	no

Training

• Base model: answerdotai/ModernBERT-base, fine-tuned with a decision head.
• Data: openly licensed public datasets (listed in NOTICE) and synthetic decisions from Qwen3.5-4B.
• Calibration: a temperature per question type, fitted on a validation split.

Training loss and learning rate (left); validation accuracy by question type (right).

Share of synthetic examples kept after verification, by question type (left) and by family (right).

Limitations

• English only.
• Long inputs are truncated.
• Rating-scale answers are less accurate than the other types.
• Probabilities are calibrated on data like the training data; validate them on your own.
• Not for high-stakes decisions (medical, legal, financial, hiring) on its own.

Train a new model

git clone https://github.com/SamratDuttaOfficial/WaterSheep
cd WaterSheep
./scripts/run.sh

Use scripts\run.bat on Windows.

Results

The figures, tables and data are in results/. To remake them after training and scripts/run-benchmarks.sh (.bat on Windows), run these from the project root with the Python in .venv:

Script	Needs	Writes to results/
tools/results/data_stats.py	a trained model	data/data_stats.json
tools/results/make_figures.py	data_stats.py, benchmarks	figures/, data/synth_outcomes_by_type.json
tools/results/gen_tables.py	data_stats.py	tables/sources.tex, tables/families.tex
tools/results/bench_table.py	benchmarks	tables/bench.tex, tables/speed.tex, data/bench_summary.json

Each uses the newest model unless --model is given.

License

Apache 2.0 (LICENSE). Attributions: NOTICE.

Citation

@misc{watersheep,
  author = {Samrat Dutta},
  title  = {WaterSheep: calibrated decisions for any text},
  year   = {2026},
  url    = {https://huggingface.co/samratduttaofficial/WaterSheep}
}

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