TYPESAFE RELEASED A MODEL THAT DOESN'T GENERATE TEXT, AND
Replaced six of eight decisions in an agent loop with Jev calls, keeping only planning steps on a chat model to cut latency and cost.
The original post
TYPESAFE RELEASED A MODEL THAT DOESN'T GENERATE TEXT, AND IT BREAKS THE COST FLOOR OF THE AGENT LOOP
jev is what they call a system one model. you send it a state and a set of questions, it returns typed answers with probabilities. no tokens, no sampling, no sequential decoding.
route → decide → guard → run tool → observe → done?
they report 20-200x faster inference and 40-400x lower cost than comparable llms on classification tasks. every question in a request is evaluated in parallel, so adding questions barely moves latency.
in a two-turn loop that means eight decisions. the two that need a plan still go to a chat model. the other six - pick a model, screen a tool call, check if the task is done - cost 0.06s combined.
the takeaway is simple: stop paying generation prices for choices. most of what an agent decides is a pick, a score or a yes/no.
Quoted post
@sydneyrunkle468.6K viewssource
Engagement when collected
Numbers are a snapshot taken from X when the case was added to the library (schema v1, collected 2026-09-19); they will not match today.
Where this case fits
Filed under agents & workflows, coding & developer tools, classification & data extraction. In the pattern Jev is built for, the model answers a bounded question per step — and ordinary code acts on the answer, because the answer is already a value rather than a paragraph. Other posts in the same family are on the agents & workflows page.
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Last updated: 2026-09-22 · sources & corrections · every card links to its author's original post