| description | TokenJuice - a rule overlay that compacts verbose tool output before it ever enters LLM context. Sweeping through thousands of emails stays cheap. |
|---|---|
| icon | file-zipper |
LLM tokens are expensive, and verbose tool output is where most of them go to die. A git status in a busy repo, a cargo build log, a 600-message email thread, a docker ps -a against a real cluster, each of these can balloon a context window for almost no information gain.
OpenHuman ships with TokenJuice, a port of vincentkoc/tokenjuice integrated directly into the tool-execution path. Before any tool result reaches the model, TokenJuice runs the output through a rule overlay that strips the noise and keeps the signal.
Rules are JSON, and they merge in this order, later layers override earlier ones:
| Layer | Path | Purpose |
|---|---|---|
| Builtin | shipped with the binary | sensible defaults for git, npm, cargo, docker, kubectl, ls, etc. |
| User | ~/.config/tokenjuice/rules/ | your personal overrides, apply across every project |
| Project | .tokenjuice/rules/ | repo-specific overrides, checked in, shared with the team |
Each rule names a tool/command pattern and a reduction strategy (truncate, dedup lines, fold whitespace, drop matching regexes, summarize sections, …). New rules are just JSON files; no recompile required.
TokenJuice is what makes auto-fetch economically viable. When the Gmail provider syncs a page of 200 messages, TokenJuice compacts each canonicalized email before it enters the model that builds summaries. The same applies to GitHub diffs, Slack channel dumps, and any other firehose source.
Concretely: ingesting your last six months of email through a frontier model costs single-digit dollars instead of hundreds.
tool call result
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TokenJuice (classify → match rule → reduce)
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LLM context
Implementation: src/openhuman/tokenjuice/ (classify.rs, reduce.rs, rules/compiler.rs, tool_integration.rs).
- Drop a JSON file in
~/.config/tokenjuice/rules/to add or override a rule globally. - Drop one in
.tokenjuice/rules/inside a repo to do the same per-project. - Start the core with
RUST_LOG=openhuman_core::openhuman::tokenjuice=debugto see what's matching and how much output is being trimmed.
- Native Tools. most heavy tool output flows through TokenJuice.
- Memory Tree. the downstream consumer of compressed output.