Atlas / Open-weight and challenger labs / Jev
Jev
AI Market Atlas · by Pro Pluribus
TypeSafe AI · San Francisco
A new kind of model that returns typed decisions, not text. $870M Series A at $7.5B (9 Oct). OpenAI, Amazon and Cloudflare now ship rivals; Jev is still the most-queried on OpenRouter.
Early adopters use it as a fast judge or guardrail for agents. VentureBeat reported that prompt injection can sway its verdicts, so it shouldn't be the only control on consequential agent actions. On public decision benchmarks, Liquid's D1 Ultra and Base Lab's Elephant-1 now lead; Jev ranks 3rd and 7th, ahead of OpenAI's Decisions API.
Same job, different name: A new category. Closest existing practice: using an LLM as a judge or classifier.
What it offers
Main offerings
- Jev (early access, 15 Sep)
- A “System One” decision model: text or JSON in; choices, yes/no answers and ratings out, each with probabilities and a confidence score. $0.042 per million input tokens; output free.
- Integrations
- Cloudflare, LangChain (LangSmith evals) and Langfuse added support within days; also on OpenRouter.
- Company
- Founded by ex-OpenAI engineer Diogo Almeida. $40M seed (Sep, DCVC), then $870M Series A (Oct, a16z with Sequoia).
Recent news
- OpenAI makes its Decisions API widely availableValidates the decision-model category Jev created; Jev still leads OpenAI on public benchmarks.TechCrunch ↗
- TypeSafe raises $870M Series A at a $7.5B valuationa16z led, with Sequoia; a decision model that never generates text, valued 19x its seed in under a month.Tech Times ↗
- Amazon releases Strands Decider 2B, an open Jev rivalDecision models attract fast followers within weeks of Jev's launch.AI Weekly (VentureBeat) ↗
- Simon Willison: Jev introduces a new shape of modelA respected independent developer calls decision models a genuinely new category, not a smaller LLM.Simon Willison ↗
- LangChain adds Jev to LangSmith EvalsPositions Jev as a third kind of agent evaluator, faster and cheaper than LLM judges.LangChain ↗
- TypeSafe AI releases Jev, returning typed, calibrated decisions instead of textTechnical overview of the API: choices, booleans and ratings with probabilities and confidence.MarkTechPost ↗
- A new kind of AI model from a ChatGPT inventor is thrilling developersMainstream coverage of the launch; developers shipped guardrails, an MCP server and clones within 48 hours.TechCrunch ↗
- TypeSafe launches Jev in early access with a $40M seed led by DCVCClaims up to 193x faster and 445x cheaper than LLMs for probabilistic decisions.Tom's Hardware ↗
- Prompt injection can influence Jev's verdictsCompanies using Jev to gate agent actions face a known attack path; treat it as one control among several.VentureBeat ↗
This map is a by-product of the work. Keeping track of what each of these actually does, and which ones are worth your time, is part of how I advise founder-led companies on AI. If you want that applied to your business, the first conversation is free.
Book a 30-minute conversation →Compiled from public sources by Pro Pluribus; updated 10 Nov 2026. General information, not advice. Company names and logos belong to their owners and are used to identify them, without affiliation or endorsement. Terms