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), under a month after launch; open rivals already appearing.
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.
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
- 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 ↗
Compiled from public sources by Pro Pluribus; updated 16 Oct 2026. General information, not advice. Company names and logos belong to their owners and are used to identify them, without affiliation or endorsement. Terms