experiments25
labeled rows504
decision modeltypesafe/jev-1.13 via OpenRouter
every numberfrom a real run

Jev Lab

Twenty-five decisions an AI product makes every day: classify, gate, route, filter, verify. Each one decided three ways: by Jev, by an LLM, and by plain code. Same rows, real API calls, every mistake counted.

New to Jev? What it is and where to find it →

Unofficial tests by Prateek Hitli, not affiliated with TypeSafe AI. Run with his own OpenRouter API key; OpenRouter is the provider for the Jev model.

20/24
projects where Jev is as accurate as the best LLM baseline, or better
2.6×
median: an LLM decision costs this many Jev decisions
10/10
no-model baselines (rules, regex, lists) that Jev beats on the same rows

Every experiment: accuracy vs cost(latest saved run of each project; click a point to open it)

JevLLM baselineFrontier / reviewNo model (rules, regex, lists)

Graded projects plot pass rate; the rest plot accuracy against the labels. No-model baselines cost $0 and sit in the “free” column.

The 25 Experiments

How Each Experiment Is Run

Jev

One decision call, typed. A Choice, a Noul (yes/no) or a Score, with calibrated probabilities. Code turns the answer into the action, so counting, facts and hard rules are never asked of a model.

LLM baseline

The same question, as a prompt. The fast model with a plain or structured-output prompt, given the same policy and inputs. Where it matters, a frontier model too.

No-model baseline

What you would write without AI. Regex, deny-lists, keyword filters, points tables, “store everything”. Free, and blind to meaning. Every dataset has rows written to test exactly that.

Measured

Against labels, on real calls. Accuracy or a graded pass rate, unsafe actions allowed, cost per passing answer, latency. Saved runs live in History; the re-test diffs them row by row.

∵ Streamlit still runs alongside: uv run streamlit run app.py