Jev on BANKING77: 77-way support-intent classification
A frozen Jev Choice setup classifies 3,080 banking support messages using category definitions and retrieved labeled training examples.
Public API code, protocol, frozen implementation, and evaluation report were inspected on October 1, 2026. The author reports 2,846 correct classifications out of 3,080 test messages, or 92.40%, using 24 BM25-retrieved training examples per request. The cited 93.66% BERT result is a published comparison, not a newly run baseline. Inputs and examples were developed on training data and frozen before the test. This is one author-run dataset evaluation; labeled examples were still required.
# Jev on BANKING77: classification without task-specific fine-tuning **An exploratory evaluation of a general-purpose decision model against a published specialist benchmark** September 18, 2026 · Model: `jev-1.13.0` ## Summary Can a general-purpose model approach the accuracy of a classifier trained for one particular task, without being fine-tuned for that task itself? We tested TypeSafe’s **Jev** on **BANKING77**, a public dataset of banking support messages with 77 intent categories. After comparing five input setups using training data only, we froze the strongest validation setup and evaluated all **3,080 official test messages**. Jev received category definitions and 24 relevant labeled training examples for each prediction; its weights were not updated. **Jev classified 2,846 messages correctly: 92.40% accuracy.** The original BANKING77 paper reports **93.66%** for a fine-tuned BERT classifier, a gap of **1.26 percentage points**. Our final test cost an estimated **US$0.44** in API usage and took **6 minutes 51 seconds** with four concurrent workers. Development and testing together cost **US$0.77**. This is encouraging evidence that Jev can provide useful classification without training a dedicated model. It is one public-benchmark result using labeled examples—not evidence that specialist classifiers are generally unnecessary or that Jev had never encountered similar data before. ## Background ### What is Jev? [TypeSafe describes Jev](https://docs.typesafe.ai/concepts/system-one) as a “System One” model: an AI model designed to make structured decisions inside software. A developer provides information, a question and the allowed answers. Jev returns a typed judgment and probabilities rather than generating a free-form reply. Its interface supports