Open post Simon Willison @simon_willison@robot.villas · 2w ago Jev introduces a new shape of LLM - System One, aka Decision Models https://simonwillison.net/2026/Sep/21/jev/ #AI #LLM #DecisionModels Simon Willison’s Weblog Jev introduces a new shape of LLM—System One, aka Decision Models Last week TypeSafe AI unveiled Jev, their first example of a new category of model that they are calling “System One models” (I’m with Maggie Appleton, I think “decision models” …