You still don't understand the use cases Jev unlocks. I've been waiting for something like this since early ChatGPT models. prediction: we will see the fastest-growing SaaS by MRR in history within the next month or two
API & ModelsPOST /v1/systemone
System One endpoint
The single HTTP endpoint that evaluates a state against typed questions: POST https://api.typesafe.ai/v1/systemone.
- Category
- API & Models
- Also known as
- POST /v1/systemone
- Related terms
- 5
- Directory entries
- 13
- Docs
- docs.typesafe.ai
- Added
- 2026-09-24
Definition
Every request carries a state, a model, and a map of typed questions. The response returns one answer per question under the same IDs, plus the model that answered and token usage.
There is no separate endpoint per primitive; Choice, Score, and Noul mix freely in one call. Official SDKs wrap this endpoint, but the HTTP contract is documented for every other language.
Tagsapicore
Related terms
Definitions that connect to this one.
API keyThe bearer credential for the TypeSafe API, created in the console and read from TYPESAFE_API_KEY by the official SDKs.API & Modelsmodel fieldThe required request field that selects which model handles the call; accepts versioned IDs and aliases.API & ModelsQuestion IDThe key you choose for a question; answers come back under the same key, and the ID is never sent to the model.PrimitivesClient SDKThe official typed clients for the API — Python and JavaScript/TypeScript — with retries and inferred answer types.API & ModelsUsageThe response field reporting input and output token counts for a request, used for cost tracking.API & Models
From the directory
The raw HTTP contract behind every SDK: POST a state plus typed noul, choice, and score questions to /v1/systemone, and get one answer per question, with error codes and retry guidance.
Sites & GuidesDocs#official#docs#api
Official
Everything you need to make your first request: install an SDK, get an API key, and send state plus typed questions.
Sites & GuidesDocs#docs#official#quickstart
Official
A public Jev API funded by creator fees from a token, with a playground, docs, use cases, and a smart treasury dashboard.
Tools & IntegrationsPlayground#community#playground#api
Community
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
@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.
Tools & IntegrationsDocs#community#vercel#integration
Community
An OpenRouter Labs recipe that has Claude rewrite a pasted prompt into Jev questions, then runs Jev on every row while a chat model races the same job, comparing answers, requests, time, cost, and accuracy.
Cookbooks & DemosPlayground#community#openrouter#playground
Community
7 more matching entries in the full directory.
From the community
Posts from builders shipping with Jev right now.
The use cases Jev unlocks
19 open-source Jev projects
一个只会做选择题的小模型，能长出多少玩法？ TypeSafe 的 Jev 就是这么个东西：给它最多 255 个选项，几百毫秒挑一个，再附一个校准过的置信度，输出 token 免费 结果开发者们已经拿它做出了 19 个开源项目，加起来 6800 多星 挑几个最有意思的 jev-ultrafast，browser-use 出品，2700 星，一句 Show more
Jev Calc: a notebook that calculates anything
i made a smart calculator notebook using jev it can calculate ANYTHING!! 😅
Day-one notes from a skeptic, in Chinese
一些关于 Jev (@typesafeai) 的 notes 研究了一天 Jev，带来的新鲜感迅速回落，这好像就是一个更快的通用分类器/决策器，LLM 完全可以做到。 而且因为不了解模型背后的参数规模（应该不会很大），世界知识可能不一定有常规 LLM Show more
@CompleteSkeptic
After co-inventing ChatGPT, I kept asking myself: why have superhuman chat models not led to AGI? I’ve spent the last 2 years in stealth building a new way to train models (RLCD), and a new type of frontier AI model that we are releasing today: Jev • 20-200x faster • 40-400x
Search and tagging on keep.md
Cloudflare Workers has Jev now so I'm putting it to the test on keep.md - 7x faster search rerank compared to the current hybrid - 50x faster tagging of content vs GLM 4.7 Flash with no failures
A filter for reply-guy comments
Pro tip: You can use Jev to remove annoying reply guy comments that X seems to always miss. Takes 5 minutes in Astra with the docs and an API key.