lossless-compaction
Claude Code plugin that compacts by moving old tool results to local files with no summary, with Jev picking which to recall by question.
Overview
lossless-compaction is a Claude Code plugin that compacts a conversation without summarising it. Claude Code's built-in /compact asks a model for a summary, which takes tens of seconds, sends a request the size of the conversation and replaces what was said. This plugin instead moves old tool results out to files on your machine, named by SHA-256, leaving a short ticket line in their place, which takes a fraction of a second and calls no model. What you and the agent said, including attachments, is stored word for word.
The agent can recall a result exactly by ticket id, or ask a find tool a question in words; with a TypeSafe key, Jev chooses which moved-out result matches. When Claude Code's own summary runs, the plugin saves what it replaces first so it can still be recalled. The README's benchmark on six kinds of synthetic conversation, run twice with Sonnet 5.5, shows the plugin writing no summaries and compacting in 0.11 to 0.48 seconds versus 15 to 27 seconds for the built-in. It requires Claude Code 2.1.287 or later.
What the decision model decides
| Type | Question | Answers |
|---|---|---|
| Choice | Which moved-out tool result best answers this recall question? | — |
How it works
- Compaction triggers in Claude Code
- Old tool results are written to local files and replaced by tickets
- No model is called for compaction
- Agent recalls a result by id, or asks find in words
- Jev chooses the matching result when a key is set
Strengths
- Very fast compaction with no model call
- Content kept verbatim and recoverable
- Saves content before built-in summaries
Caveats
- Moved content is out of sight until recalled
- find needs a Jev key
- Depends on recent Claude Code features
Getting started
/plugin install lossless-compaction --marketplace yottayoshida/lossless-compaction in Claude Code 2.1.287+.At a glance
- Type
- Plugin
- Status
- beta
- Language
- TypeScript
- Runtime
- Claude Code plugin
- Has code
- yes
- Has tests
- yes
Use cases and integrations
How curated lists describe it
Context management: Claude Code plugin that compacts by moving old tool results to local files with no summary, and asks Jev a `Choice` over what was moved out to fetch one back by a question in words.
yibie/awesome-jevClaude Code plugin that moves old tool results to local files instead of summarizing them, and asks Jev a choice over what was moved out when its `find` tool is given a question in words; the compaction itself calls no model.
cobanov/awesome-jev
Frequently asked questions
Does it summarise my conversation?
No, it moves old tool results to local files verbatim.
What does Jev decide?
Which moved-out result matches a recall question asked in words.
How fast is it?
0.11-0.48 seconds per compaction in the README's benchmark.
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