What does Pi Jev Compaction do?

It compacts long coding sessions by asking Jev to judge complete read-only tool pairs — reads, greps, finds and ls calls — and then uses ordinary code to remove the pairs it rates as unnecessary, keeping the evidence that still matters.

Does Jev write the summary?

No. The package does not generate a summary: Pi's compaction API accepts a summary string, so the extension puts an extractive transcript packet there and preserves Pi's native recent-message boundary. Retained records stay in chronological order.

Which tool calls can be removed?

Only uniquely paired, successful read, grep, find and ls calls outside the protected recent span, where the full serialized call and result fit within 8,000 UTF-8 bytes. The full call and result are sent with each noul question, not just an ID.

What is the removal threshold?

A probability below 0.35 removes the call and its result together; higher values retain both. There is no output truncation and no generative summary step in the successful extension path.

Run pi install git:github.com/Wang-auspicious/pi-jev-compaction@v0.1.0, export TYPESAFE_API_KEY, and start pi. In an existing session, run /reload after installing and /compact when you want to compact; no npm publication is required.

Does it patch Pi or rewrite my session file?

No. The README says it does not patch Pi, rewrite the session file, or pretend Pi supports replacing arbitrary history messages; it works within the compaction API Pi exposes, and Pi still needs its normal conversation model and authentication.

Jev directory

CommunityJev Agents & MCP

Pi · Jev Compaction

Decision-driven, extractive context compaction for the Pi coding agent: Jev judges complete read-only tool pairs and ordinary code removes the ones it rates unnecessary, keeping retained records in a JSON-lines transcript packet instead of a generated summary.

See highlights Open github.com

Stars: 1
Language: TypeScript
License: MIT
Reading time: 2 min
Published by: Community
Author: wang-auspicious
Last verified: Oct 2026

wang-auspicious/pi-jev-compaction

User repository on GitHub

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Jev-powered context compaction for Pi. Keep critical instructions and tool history, prune the noise, and fall back gracefully.

Forks: 0
Last pushed: Updated Sep 2026

Repo stats from the GitHub API, cached Oct 2026.

Tagscommunity catalog-import logicrw pi context-compaction

Works forJev for Tool calling Jev for Decision gating

Used inJev for Software & DevTools

Languages: TypeScript
Platforms: CLI
Capabilities: Open sourceRequires API key

Highlights

Only uniquely paired, successful read, grep, find and ls calls outside the protected recent span are candidates; each must fit within 8,000 UTF-8 bytes.
Each noul question carries the complete candidate call and result, not an ID or an output length; shared state includes the latest three user instructions.
A probability below 0.35 removes the call and its result together; higher values retain both, and there is no output truncation.
Requires Node.js 22.19+ and Pi 0.84.2, the version actually validated; the release tarball is a self-contained install and no npm publication is required.
Inspired by tamaratran/fast-jev-compaction, with a Pi-specific lifecycle adapter and a conservative selection policy.

Quickstart

bash

pi install git:github.com/Wang-auspicious/[email protected]
export TYPESAFE_API_KEY="your-typesafe-key"
pi

Watch out

Copy reviewed against the repo README on 2026-10-15; the README is truncated mid-sentence in the digest and points to docs/verification.md rather than publishing benchmarks inline. It states that older Pi versions and the former @mariozechner package namespace are not claimed as supported.

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