Microsoft-Decision-1 Explained: Microsoft Joins the Decision Model Race, Compared with Jev and Laya

Introduction Last month I wrote Jev vs Laya, comparing TypeSafe AI’s closed-source decision model Jev with the community’s open-source Laya. Back then, “decision models” were a brand-new category: Jev launched on September 15, and Laya was open-sourced three days later. Just three weeks later, the field is crowded: on October 6, OpenAI opened its Decisions API built on GPT-6 Luna; companies such as Liquid AI and Inception have launched their own decision APIs; and the third-party leaderboard JevBench now ranks more than 140 open-weight systems....

October 10, 2026 · 26 min

Jev vs Laya: Comparing and Choosing Between Closed-Source and Open-Source System One Decision Models

Introduction In September 2026, a new kind of model that “doesn’t talk” suddenly became the talk of the AI world. On September 15, TypeSafe AI, founded by former OpenAI researcher Diogo Almeida, released Jev. It doesn’t chat, write articles, or generate code. It takes a piece of state and a set of predefined questions, and directly returns structured decisions with calibrated probabilities. Just three days later, on September 18, independent researcher Nandakishor M (Convai Innovations) open-sourced Laya....

September 23, 2026 · 25 min