Skip to content
JevDirectory.org
CommunityTools & IntegrationsDocsVerified 2026-09-22

TypeSafe Provider

@ai-sdk/typesafe-ai adds an evaluation model to the Vercel AI SDK: one experimental_evaluate call sends a state with choice, score, and boolean questions and returns typed answers, probabilities, confidence, and usage.

Open ai-sdk.dev
Category
Tools & Integrations
Published by
Community
Author
—
Added
2026-09-22
Tagscommunityvercelintegrationapievaluation

Highlights

  • Install @ai-sdk/typesafe-ai, set TYPESAFE_AI_API_KEY, and evaluate with typeSafeAi.evaluationModel('jev-latest').
  • Choice takes 1-255 options, Score 2-10 ordered levels, and the SDK's boolean maps to TypeSafe's Noul as P(true).
  • Answers arrive rounded to two decimals; result.rounding reports the precision, so probability sums can miss exactly one.
  • Confidence for Choice and Score sits under result.providerMetadata.typesafe.confidence[questionId], apart from probabilities.
  • Failures raise APICallError; the SDK retries 429 and 529 up to maxRetries (default 2), with no provider-side retry loop.

Quickstart

ts
import { typeSafeAi } from '@ai-sdk/typesafe-ai';
import { experimental_evaluate } from 'ai';

const result = await experimental_evaluate({
  model: typeSafeAi.evaluationModel('jev-latest'),
  state: { message: 'I was charged twice. Please refund the duplicate.' },
  questions: {
    department: {
      type: 'choice',
      instructions: 'Which team should handle this?',
      criteria: { billing: ['Charges', 'Refunds'], technical: ['Bugs'], other: null },
    },
  },
});

console.log(result.answers.department.choice);

Watch out

Only the experimental evaluation API is supported - language, embedding, and image model factories throw NoSuchModelError - and the page is Vercel's, not TypeSafe's.

More like this

Vercel AI Gateway: Evaluation Models
AI Gateway's evaluation modality: call Jev as `typesafe-ai/jev` through the AI SDK's experimental_evaluate API, with structured answers instead of free-form text.
Tools & IntegrationsDocs#community#vercel#integration
Community
AI CLI
811GitHub stars
Vercel Labs' terminal CLI for the AI SDK: its `ai evaluate` command answers named Boolean, Choice, and Score questions, with Jev as the default evaluation model and one unchanged input shared across all questions.
Tools & Integrations#community#typescript#cli
Communityai-cli
Jev on Workers AI
Cloudflare Workers AI's model page for typesafe/jev: run the structured evaluation model through an env.AI.run binding or the REST /ai/run endpoint, with typed Noul, Choice, and Score questions and worked examples.
Tools & IntegrationsDocs#community#cloudflare#integration
Community
Back to all resources

From the community

Posts from builders shipping with Jev right now.

Follow @typesafeai

Six uses that stuck after 60 days

Security decisions that fit Jev

Kostas
Kostas
@Kostastsale
·

This made me rethink where AI actually fits into security engineering. For purely engineering work, forget about ChatGPT or Claude. TypeSafe AI just released Jev, and I think it’s going to change how we build AI into security workflows. Instead of asking an LLM to “investigate Show more

TypeSafe AI
TypeSafe AI
@typesafeai

we are officially out of stealth! join the frontier and get access to Jev on our website (link on profile)

Reply
Read 14 replies

A million judged questions

Inferring Jev's internals from 1,000 calls

iwashi / Yoshimasa Iwase
iwashi / Yoshimasa Iwase
@iwashi86
·

Jevの内部アーキテクチャを推測している技術記事(Jev’s Architecture Unmasked)からメモ。 ・本記事はJevのAPIを約1万回の呼び出して、内部構造を推測したもの ・従来の言語モデルを用いた分類やルーティングでは、トークンを1文字ずつ逐次生成するために膨大な無駄な計算コストが発生していた。 Show more

Reply
Read 2 replies

The open System One roundup

小墨同学
小墨同学
@xiaomovps
·

Jev 发布没几天，开源社区已经开始疯狂复刻了🔥 最值得推荐的五个模型： 1、Laya 421M：原生决策模型，支持 Mac 2、Decider-2B：最像 Jev，基于 Qwen3.5 3、NanoJev 0.6B：专门的 Decision Head 4、Reflex：Qwen3.5 + Direct Logits 5、System-One 4B：专门做概率校准 Show more

小墨同学
小墨同学
@xiaomovps

Jev 刚发布没几天，开源社区就出现了同款🔥 Decider-2B模型，是基于 Qwen3.5-2B 做了特殊调整 它和 Jev 模型是一样的 只做选择 评分和判断 不是文本类的 LLM 模型 但两者还是有几个明显区别： 1、模型 Jev：闭源 System One Model Decider：Qwen3.5-2B，约 1.9B 参数，Apache 2.0 开源 2、价格

Image
Reply
Read 6 replies

The launch post