Jev × LexGLUE
Zero-shot run of Jev 1.13 on all seven LexGLUE legal tasks (23,607 examples) versus GPT-5.6 Luna, open models and fine-tuned BERT.
Overview
Jev × LexGLUE is a reproducible zero-shot benchmark of Jev on all seven LexGLUE legal NLP tasks. It freezes official test examples and sends typed decisions through OpenRouter's systemone endpoint: single-label examples become one Choice, and multi-label examples become one request with an independent Noul per label, with no chat completions or output parsing. Every completed request is checkpointed and reports cover micro and macro F1, usage and cost.
On 23,607 test examples the README reports Jev at 69.9 mean micro-F1 for $4.02, against GPT-5.6 Luna via chat JSON at 71.3 for $16.45; tuning per-label thresholds on the validation split raised Jev to 74.2. Jev beat open Kev-4B on all seven tasks, Clef-flash scored 68.3, and fine-tuned BERT-base scored 77.4, leading by 13 to 29 points on EUR-LEX, LEDGAR and UNFAIR-ToS while both decision models beat it on CaseHOLD.
What the decision model decides
| Type | Question | Answers |
|---|---|---|
| Choice | Which label applies to this legal text (single-label tasks)? | — |
| Yes / no | Does this label apply (one per label for multi-label tasks)? | — |
How it works
- Freeze LexGLUE test examples
- Send Choice or per-label Noul requests via OpenRouter
- Checkpoint each request
- Compute F1, usage and cost; compare baselines
Strengths
- Full-test-set evaluation
- Cheap relative to an LLM with similar accuracy
- Validation-tuned threshold variant
Caveats
- Trails fine-tuned BERT on several tasks
- Zero-shot only
At a glance
- Type
- Project
- Status
- research
- Language
- Python
- Runtime
- Benchmark scripts via OpenRouter
- Has code
- yes
Use cases and integrations
How curated lists describe it
Reproducible zero-shot run of Jev 1.13 (`typesafe/jev-1.13-20260917`) on all seven LexGLUE tasks, 23,607 test examples: mean micro-F1 69.9 at $4.02, against 71.3 at $16.45 for GPT-5.6 Luna via chat JSON
AnotiaWang/awesome-decision-models
Frequently asked questions
How did Jev score?
69.9 mean micro-F1 zero-shot, or 74.2 with validation-tuned thresholds.
How does it compare to an LLM?
Close to GPT-5.6 Luna's 71.3 at about a quarter of the cost.
Does fine-tuning still win?
Fine-tuned BERT scored 77.4 overall.
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