shitianfang/jev-use

10 stars · Last commit 2026-09-20

Claude Code / Codex / pi plugin that hands agent steps needing no text output to Jev (TypeSafe's judgment model) — measured p50 ~230 ms and ~$0.02 per 1,000 judgments, with typed escalation back to the LLM

README preview

# jev-use

**English** | [简体中文](README.zh-CN.md)

The best way for Claude Code, Codex, and [pi](https://github.com/badlogic/pi-mono)
to work with [Jev](https://typesafe.ai/blog/introducing-system-one-models-and-jev):
hand the tasks that need no text output to Jev — faster steps, fewer
tokens, tasks done sooner and better.

It makes the LLM and Jev true collaborators: when content needs to be
written, the LLM takes over; when a step just needs a fast decision, Jev
executes it.

## Demos — real runs, 1× speed

<table>
<tr>
<td width="50%" valign="top"><b>Directions task: Jev clicks, the LLM types</b> — 10 decisions (p50 274 ms) · 4 writes; Jev rejects a wrong route, the LLM rewrites<br><img src="assets/collab.gif" alt="OpenStreetMap directions: Jev picks controls in green, the LLM types the locations in blue; a wrong 1809km geocode is rejected by Jev and repaired by the LLM, ending on the real 3.7km walking route" width="100%"></td>
<td width="50%" valign="top"><b>Context compaction</b> — 200 messages judged in 7 calls, one LLM paragraph replaces the dropped pile; recall 3/3<br><img src="assets/compact.gif" alt="A real transcript fills the context window to 94%; Jev tints each message keep or drop, the LLM's summary paragraph replaces the dropped block, the window falls to 44% and three recall checks pass" width="100%"></td>
</tr>

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