Lossless Claude

License: Apache 2.0 Version Node TypeScript MCP Status: alpha

Bridges lossless-claw (LCM) into Claude Code as a cross-runtime memory layer. Sits beside Claude Code's harness and shares the OpenClaw lossless-claw SQLite database, so Claude Code sessions can read from and contribute to the same hierarchical memory store that Daphne and other OpenClaw agents use.

What this is and is not

This is: a read-mostly memory bridge that exposes LCM recall tools to Claude Code via MCP, captures Claude Code sessions on PreCompact, and bootstraps relevant context on SessionStart.

This is not: a replacement for Claude Code's built-in context management. Claude Code's harness still owns the active context window and decides when to compact. lossless-claude lives outside that loop, providing recall and persistence around it.

Architecture

┌─────────────────────────────────────────────────────────┐
│                  Claude Code Session                    │
│                                                         │
│  [SessionStart hook] ──── reads ──→  ┌────────────┐    │
│                                       │            │    │
│  [Active context]                     │  LCM       │    │
│  (managed by harness — opaque)        │  SQLite    │    │
│                                       │            │    │
│  [PreCompact hook]  ──── writes ──→   │  ~/.opencl │    │
│                                       │  aw/lcm.db │    │
│  [MCP tools] ───── queries ─────→     │            │    │
│   lcm_grep, lcm_describe, lcm_stats   └────────────┘    │
└─────────────────────────────────────────────────────────┘
        ↑                                    ↑
        │                                    │
   shared with the OpenClaw runtime (Daphne, JelleeBean, etc.)

Components

Component	Type	Purpose
lcm_grep	MCP tool	FTS5/LIKE search across messages and summaries
lcm_describe	MCP tool	Look up message or summary by ID with DAG lineage
lcm_stats	MCP tool	Database health snapshot, prefix breakdown
lcm_expand_query	MCP tool (stub)	v2 — full LLM-driven recursive expansion
pre-compact.sh	Hook (PreCompact)	Captures session messages into LCM before compaction
session-start.sh	Hook (SessionStart)	Injects recent CC + Daphne activity as bootstrap context
lcm-recall	Skill	Teaches Claude when and how to use the recall tools

Prerequisites

• Node 22+ — required for the MCP server (uses better-sqlite3)
• Python 3 — required for the hook scripts (uses sqlite3 from stdlib)
• ~/.openclaw/lcm.db — must exist. Run lossless-claw at least once via OpenClaw to create it. Override with LCM_DB_PATH env var if you want a separate database for Claude Code.

Install

# 1. Clone
git clone https://github.com/offendingcommit/lossless-claude ~/lossless-claude
cd ~/lossless-claude

# 2. Build the MCP server
cd mcp-server
pnpm install   # or npm install
pnpm build     # or npm run build
cd ..

# 3. Add to Claude Code as a plugin
# (User-level — applies to all Claude Code sessions)
mkdir -p ~/.claude/plugins
ln -s ~/lossless-claude ~/.claude/plugins/lossless-claude

After symlinking, restart Claude Code. The MCP server, hooks, and skill load automatically.

Verify the install

In Claude Code:

/mcp                    # should list "lossless-claude" as connected

Then test the tools:

Use lcm_stats to show me the database snapshot.

Configuration

Env var	Default	Purpose
LCM_DB_PATH	~/.openclaw/lcm.db	Path to the lossless-claw SQLite database
LOSSLESS_CLAUDE_LOG	~/.openclaw/logs/lossless-claude.log	PreCompact hook log file
LOSSLESS_CLAUDE_WATERMARK_FILE	~/.openclaw/lossless-claude-watermarks.json	PreCompact hook watermark store. Tracks per-session-key insert counts so overlapping PreCompact firings never insert the same message twice.
LOSSLESS_CLAUDE_BOOTSTRAP_TURNS	12	Max turns to inject in SessionStart bootstrap
LOSSLESS_CLAUDE_BOOTSTRAP_INCLUDE_AGENTS	0	When set to 1, include cross-runtime activity from OpenClaw agents (agent:main:* session keys) in the SessionStart bootstrap. OFF by default because that data can include Discord DMs and other sensitive material that should not silently leak into a new session's system prompt.

Session keying

Claude Code sessions are written to LCM with session_key = cc:<basename(cwd)>:<git-branch>. This namespaces them under cc: so they're easy to filter via lcm_grep(session_key_prefix: "cc:") and they don't collide with the agent:* keys that OpenClaw uses.

Example session keys you'll see in the database:

Session key	Source
cc:lossless-claude:main	This repo, working on the main branch in Claude Code
cc:offendingcommit-site:feature/auth	Some other repo on a feature branch
agent:main:discord:dm:123	Daphne in OpenClaw, in a Discord DM
agent:jellybean:discord:dm:456	JelleeBean in OpenClaw

Why this design

• Claude Code's harness owns the context window. Replacing its compaction is not a supported extension point. lossless-claude works beside the harness, not inside it.
• Direct SQL instead of importing lossless-claw internals. The lossless-claw schema is migration-versioned and stable. Importing LcmContextEngine would couple us to OpenClaw runtime symbols. Talking to SQLite directly via better-sqlite3 keeps the bridge thin and decouples upgrade cycles.
• Read-mostly. The MCP server is strictly read-only (PRAGMA query_only = ON). Only the PreCompact hook writes, and only to its own cc: namespace, so we never trample OpenClaw's data.
• Cross-runtime recall is the killer feature. Daphne writes to LCM via OpenClaw at 7 AM; you open Claude Code at 2 PM and it can recall what was discussed — no copy/paste, no manual export.

Roadmap

• v0.1 (current) — lcm_grep, lcm_describe, lcm_stats, PreCompact + SessionStart hooks, lcm-recall skill
• v0.2 — lcm_expand_query with LLM-driven recursive DAG walk
• v0.3 — periodic compaction job that runs lossless-claw's summarizer over cc:* conversations
• v0.4 — /lossless-claude slash command for ad-hoc DB inspection from inside Claude Code

License

Apache-2.0