What does the plugin rewrite, and what stays untouched?

Only the outgoing model request: stale tool calls are dropped and bulky results truncated there. Stored history, /compact, and automatic compaction are untouched, and the live turn plus configured protected tool calls stay in place by default.

What happens when Jev is down or the key is missing?

It fails open. A missing key, timeout, transport or HTTP error, malformed answer, or unreadable config leaves the request unmodified, and without a key the plugin stands down and logs the reason.

How do I install it into OpenCode?

Clone the repository into ~/.config/opencode/plugins/fast-jev (or a project's .opencode/plugins/), optionally copy config.example.json to config.json, and restart the server with opencode service restart. There is nothing to build.

Where does it read the Jev key from?

From TYPESAFE_API_KEY first, then from ~/.config/opencode/.env, the file the jev CLI uses, read per request. Without a key it stands down and logs the reason rather than erroring.

Will it start pruning as soon as I install it?

No. The shipped defaults and config.example.json are observe-only (enabled: true, dryRun: true), so decisions are scored and logged while requests pass through; setting dryRun to false in config.json turns pruning on.

What does the /jev-prune command show?

A report: whether the plugin is enabled or dry-run, cached decisions, how many calls would be dropped at the current keepThreshold, and the last run's drops, truncations, saved percentage, and latency. It reports, it does not trigger pruning.

Which OpenCode versions is the plugin built for?

It is built and validated against OpenCode v2.0.7, with a runtime fixture pinned to a real context-hook payload from that version, and CI type-checks the SDK contracts against @opencode/plugin 2.0.7 and 2.0.8.

Jev directory

CommunityJev Agents & MCP

Fast Jev OpenCode

An OpenCode plugin that prunes stale tool calls and truncates bulky results on the outgoing V2 request using Jev, leaving stored history untouched and failing open when Jev is unreachable.

See highlights Open github.com

Stars: 8
Language: TypeScript
License: MIT
Reading time: 2 min
Published by: Community
Author: nrdz-labs
Last verified: Oct 2026

nrdz-labs/fast-jev-opencode

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Jev-scored context pruning for OpenCode: drops stale tool calls and truncates bulky results on the outgoing request — fail-open, cache-backed, configurable live. Port of fast-jev-compaction to the V2 context hook.

Forks: 0
Last pushed: Updated Sep 2026

Repo stats from the GitHub API, cached Oct 2026.

Tagscommunity typescript opencode context compaction

Works forJev for Tool calling Jev for Decision gating

Used inJev for Software & DevTools

Languages: TypeScript
Capabilities: Open sourceRequires API key

Highlights

Prunes stale tool calls and bulky results from OpenCode V2 requests through the context hook.
Fails open: a missing key, timeout, transport error, malformed answer or unreadable config leaves the request unmodified.
Ships observe-only with dryRun: true; live mode is one edit, and config.json is re-read on mtime change.
No build and no runtime dependency: only node: builtins and its own files; the key comes from TYPESAFE_API_KEY or OpenCode's .env.
Built and validated against OpenCode v2.0.7, with CI type-checking against @opencode/plugin 2.0.7 and 2.0.8.

Watch out

MIT, but young: validation is pinned to OpenCode v2.0.7 and plugin 2.0.7-2.0.8, so newer context-hook payloads may need updates. Going live needs a TypeSafe key, and the fail-open design means a broken Jev path silently leaves requests unpruned.

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