Why not just hand-write the JSON and call Jev once?

Hand-written JSON forces you to escape every line break and quote by yourself, and one answer only shows a single probability. The builder writes valid JSON as you type and records distributions, spread, confidence, latency, tokens, and cost across repeated runs.

Does my text or API key leave the browser?

No. The page runs locally with no cookies, analytics, or third-party requests, and it never asks for a key. The local runner reads TYPESAFE_API_KEY from the environment or a beside-the-repo .env on the server side only and never sends it to the page.

What do the robustness probes actually change?

They rerun the same request with meaning-free changes such as spacing, code fences, filler, manufactured confidence, appeals to authority, politeness, and reversed options. The probe names match dinostomp, so a finding here means the same thing there.

When should I switch to dinostomp instead?

When you need labelled data, pre-registered thresholds, and a findings ledger. The builder states it has no datasets, leaderboard, or account, and it can write a dinostomp check file for that step.

How many runs does the builder keep, and where?

Runs are kept in the browser's local storage, up to 200, and can be cleared per question; the hosted page uses Paste a response, while live runs need the local runner on 127.0.0.1 with your own key.

Can I run it against my own gateway or a mock?

Yes. JEV_URL in scripts/serve.mjs is one constant, so you can point it at a gateway, a proxy with your own quota, or a mock while you work offline.

How many templates does it ship?

34 templates across support, moderation, writing, sales, research, engineering, and AI evaluation, and six carry a second constant field such as a refund policy or routing rules so the question is judged against a rule.

CommunityJev Demos & Experiments

Jev Builder

Browser page that turns pasted text and a plain-language question into a runnable Jev request, then keeps every run so you can check whether the answer holds steady.

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Open github.com

Stars: 3
Language: JavaScript
Published by: Community
Author: collapseindex
Last verified: Oct 2026

collapseindex/jev-builder

User repository on GitHub

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A browser form for building requests to TypeSafe's Jev: pick a template, fill in the blanks, copy the request. No JSON, no install, runs locally.

Forks: 0
Last pushed: Updated Sep 2026

Repo stats from the GitHub API, cached Oct 2026.Homepage

About this project

v1.19.0 · Open the tool · Apache-2.0. Type or paste your text, say what you want TypeSafe's Jev to decide about it, and get a request you can run. Then run it a few times and see whether the answer holds. The text goes in as it is; the request is written as you type. Writing a Jev request by hand is annoying in two different ways.

Quoted from the project's README. Read the full README.

Tagscommunity awesomejev catalog-import

Works forJev for Classification Jev for Routing

Used inJev for Software & DevTools

Languages: JavaScript

Highlights

Writes request JSON as you type with browser JSON.stringify, so line breaks and quotes stay valid.
Supports noul, score, and choice questions, with 34 starter templates across support, moderation, and engineering.
Shows the request as full JSON, Playground panes, Python snippet, or curl, with one-click copy.
Live runs need local npm start with TYPESAFE_API_KEY; the hosted page uses Paste a response instead.

Watch out

Jev blocks cross-origin browser calls, so live runs need the local runner on 127.0.0.1 and the hosted page falls back to Paste a response; runs stay in local storage up to 200. Copy reviewed against the repository README on 2026-10-04, not from running it.

Questions about this entry

Short answers drawn from the linked project or page.

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