jev-cli
Node/Bun CLI for asking Jev boolean, choice and score questions over text or JSON, with direct or Vercel AI Gateway providers.
Overview
jev-cli by jtsang4 is a command-line interface for Jev with English and Chinese documentation. You give it a state and typed questions and get structured JSON back. The README example evaluates a support exchange, asking whether a refund was issued (boolean probability 0.99), which tone the agent used (warm at 0.98 versus curt), and how well it was handled on a poor/acceptable/excellent scale (score 1.78). It positions Jev as a good fit for classification, routing, rubric scoring and automated verification and a poor fit for writing.
It installs globally from npm or Bun as @jtsang/jev-cli and runs on Node 22+ or Bun. Configuration is set up with config init and config set, with the default provider calling TypeSafe directly and an alternative routing through the Vercel AI Gateway. A doctor command sends one tiny evaluation to confirm the key and model work. It is MIT licensed.
What the decision model decides
| Type | Question | Answers |
|---|---|---|
| Yes / no | Was a refund issued? | yes · no |
| Choice | What tone did the agent use? | warm · curt |
| Score | Rate how well this was handled. | poor · acceptable · excellent |
How it works
- Install and run config init
- Set the provider key; run doctor
- jev-cli eval with state and questions
- Consume JSON output
Strengths
- Simple setup with health check
- Two provider options
- Clear JSON output
Caveats
- Requires a TypeSafe or Vercel AI Gateway key
Getting started
`npm install -g @jtsang/jev-cli`, then `jev-cli config init` and `jev-cli doctor`.At a glance
- Type
- CLI
- Status
- beta
- Language
- TypeScript
- Runtime
- Node 22+ or Bun CLI
- Has code
- yes
- License
- MIT
Use cases and integrations
How curated lists describe it
A CLI for asking Jev classification, yes/no and scoring questions over text or JSON input.
logicrw/awesome-jev-projectsCLI for TypeSafe AI's Jev evaluation model — typed questions in, structured JSON answers out.
hellogumbo/awesome-jev
Frequently asked questions
What does jev-cli return?
JSON with a probability, choice or score for each question.
Can I use Vercel AI Gateway?
Yes, set provider to vercel.
How do I check my setup?
Run jev-cli doctor.
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