Context Manager for Claude Code

Automatic session summarization, archival, and context injection for Claude Code. No more lossy /compact. Sessions are summarized before compaction, archived permanently, and injected into the next session automatically.

Created by: Jonohobs + Claude Code (Anthropic) Date: 2026-03-18 License: MIT

How It Works

Session in progress
    ↓ (context getting full)
PreCompact hook fires
    ↓
Summarizer runs (Gemini CLI → Ollama → fallback)
    ↓
Summary saved to session-buffer.md + archive/
    ↓
User does /clear
    ↓
SessionStart hook injects previous session summary
    ↓
Fresh context with full continuity

Components

Component	What it does
pre-compact-summary.py	Reads observation logs, generates rich session summary via LLM (Gemini/Ollama) or structured fallback
pre-compact-summary.sh	Bash wrapper for the hook system
activity-timeline.sh	SessionStart hook — injects previous session summary + recent activity
observation-logger.sh	PostToolUse hook — logs tool usage to daily JSONL
session-digest.sh	Stop hook — generates compact session digest
obs-log.py	Python core for observation logging
digest-gen.py	Python core for digest generation
settings-hooks.json	Hook configuration to merge into your settings.json

Installation

1. Run the install script:

   ./install.sh

   Or manually copy hook scripts to ~/.claude/hooks/:

   cp pre-compact-summary.py ~/.claude/hooks/
   cp pre-compact-summary.sh ~/.claude/hooks/
   cp activity-timeline.sh ~/.claude/hooks/
   cp observation-logger.sh ~/.claude/hooks/
   cp session-digest.sh ~/.claude/hooks/
   cp obs-log.py ~/.claude/hooks/
   cp digest-gen.py ~/.claude/hooks/
   chmod +x ~/.claude/hooks/*.sh

2. Merge settings-hooks.json into your ~/.claude/settings.json
3. Ensure either gemini CLI or ollama is installed (both are free)
4. Create the log directory: mkdir -p ~/.claude/memory-log/archive

Requirements

• Claude Code
• Python 3 (standard library only)
• One of: Gemini CLI (free), Ollama with llama3 (free), or neither (uses structured fallback)

Architecture

The system uses Claude Code's hook events:

• PreCompact — fires before context compaction, generates and archives session summary
• SessionStart — fires on new session or /clear, injects previous session's summary
• PostToolUse — logs observations to daily JSONL file
• Stop — generates compact session digest appended to session-log.md

Summary Quality Tiers

1. Gemini CLI (best free option) — semantic understanding of what was accomplished
2. Ollama llama3 (local, free) — good quality, zero network
3. Structured fallback (no LLM) — tool counts, files touched, key actions from JSONL

Archive Format

Each session is archived permanently:

~/.claude/memory-log/archive/
├── 2026-03-18-14-30-session.md
├── 2026-03-18-16-45-session.md
└── ...

Sessions include tags (#project-name, #feature, #bugfix) for searchability.

The Problem This Solves

Claude Code's /compact is lossy — it compresses the conversation but loses nuance, decisions, and context. This system:

• Captures a high-quality summary BEFORE compaction
• Archives it permanently (never lose session history)
• Injects it into the next session (seamless continuity)
• Uses free LLMs (zero API cost)
• Tags sessions for searchability

Credits

This system emerged from a session on context engineering for Claude Code, exploring how to maintain continuity across sessions without relying on lossy compaction.

• Jonathan Hobman (@Jonohobs) — architecture, requirements, testing
• Claude Code (Anthropic, Claude Sonnet 4.6) — implementation, hook system design

License

MIT — use it, fork it, improve it.