Context Pruning Plugin

Dynamic context pruning for token optimization in OpenSIN CLI.

Overview

The Context Pruning Plugin automatically detects when conversation context exceeds token limits and intelligently prunes older messages while preserving critical information.

Installation

bun add @opensin/plugin-context-pruning

Configuration

{
  "maxTokens": 8000,
  "keepLastN": 4,
  "keepSystemPrompt": true,
  "keepRecentToolOutputs": 2
}

Usage

import { ContextPruningPlugin, pruneContext, countTokens } from '@opensin/plugin-context-pruning';

const plugin = new ContextPruningPlugin({ maxTokens: 8000 });
const result = plugin.prune(messages);
console.log(`Pruned ${result.prunedCount} messages`);

API

countTokens(text: string): number

Estimate token count for a string.

countContextTokens(messages: ContextMessage[]): TokenCount

Count tokens across all messages, broken down by role.

pruneContext(messages, config): PruningResult

Prune messages that exceed token limit.

ContextPruningPlugin

Class with shouldPrune(), prune(), getConfig(), setConfig() methods.

Testing

bun test
# 12 tests passing

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Relevante Mandate

Mandat	Priority	Regel
Bun-Only	-1.5	bun install / bun run statt npm
Annahmen-Verbot	-5.0	KEINE Diagnose ohne Beweis
Test-Beweis-Pflicht	0.0	KEIN "Done" ohne echten Test-Lauf

→ Alle Mandate