Agent loops use a full-size LLM call every time, even for
Wrote a LangChain blog post titled 'Building a Harness with Jev' explaining how Jev replaces full LLM calls for simple yes/no agent loop decisions.
The original post, translated
Agent loops use a full-size LLM call every time, even for simple yes/no decisions, so there's actually a lot of waste. I'll introduce a new way to use models that solves this. Title: Building a Harness with Jev URL: https:// langchain.com/blog/building- a-harness-with-jev … ❓ What's new about Jev? 💡 TypeSafe
Show the original post in its source language ▾
エージェントのループって、単純なyes/no判定ですら毎回フルサイズのLLM呼び出しを使っていて、実は無駄が多いんです。それを解決する新しいモデルの使い方を紹介します。 タイトル: Building a Harness with Jev URL: https:// langchain.com/blog/building- a-harness-with-jev … ❓ Jevって何が新しいの? 💡 TypeSafe
The post above is a machine translation from ja; the untranslated text is in the fold-out.
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. 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