Claude Code Memory

A Claude Code plugin that gives Claude fully automatic, per-project cognitive memory — powered by local embeddings and hybrid search.

Features

• Auto-loads relevant context at session start using git signals (branch, commits, modified files)
• Auto-saves a structured session summary when the session ends
• Auto-recalls matching memories when Bash errors occur
• Auto-merges near-duplicate memories on store (≥95% cosine similarity)
• Auto-consolidates based on activity weight — reviews duplicates, stale entries, and emerging patterns
• Adaptive context budget — dynamically allocates injection slots based on result quality, not fixed caps
• Two-phase recency scoring — strongly favors recent work (0–7 days) with gradual long-term decay
• Content-length penalty — prevents verbose, generic memories from dominating search results
• Noise filtering — suppresses trivial sessions, junk procedurals, and low-substance episodics

All data stays local. Everything is scoped to the current project via the working directory.

Requirements

• Node.js >= 18
• Claude Code CLI

Installation

git clone https://github.com/d2a8k3u/claude-code-memory.git claude-memory
cd claude-memory
./install.sh

The installer builds the MCP server, registers it globally, adds hooks to ~/.claude/settings.json, and symlinks skills. Restart Claude Code after installation.

Note: On first use, the plugin downloads a ~90 MB embedding model (all-MiniLM-L6-v2) from Hugging Face. This happens once and is cached locally. The first session start may take 10-30 seconds depending on your connection.

First-run bootstrap (optional)

Run /memory-init in any project to populate the memory from existing project files (README, package.json, CLAUDE.md, git history, etc.).

How It Works

Session Lifecycle

1. SessionStart — clears working memories, decays stale importance, injects relevant context via adaptive budget allocation
2. During session — Claude uses 10 MCP tools automatically (store, search, get, update, delete, list, batch-store, relate, graph, health)
3. PostToolUse — on Bash errors, extracts error terms and surfaces matching memories
4. Stop — analyzes the session transcript with noise filtering and saves structured memories (episodic, procedural, semantic, pattern)

Memory Types

| Type | Purpose | Example | |------|---------|---------| | episodic | What happened | "Fixed auth bug — missing null check on refresh token" | | semantic | Project facts | "API uses JWT with refresh token rotation, tokens in Redis" | | procedural | How-to | "Deploy: merge to develop, CI builds, auto-deploy to staging" | | working | Session scratchpad | Hypotheses, intermediate results (auto-cleared next session) | | pattern | Consolidated insights | "Error handling: always use Result types with typed errors" |

Memories can be linked with relations: relates_to, depends_on, contradicts, extends, implements, derived_from.

Search & Scoring

Hybrid search combining FTS5 full-text and semantic vectors (cosine similarity via sqlite-vec). Falls back to text-only when embeddings are unavailable. Results are reranked with a cross-encoder (ms-marco-TinyBERT-L-2-v2) for accurate relevance scoring.

Scoring combines text relevance, importance, recency, and access frequency with configurable per-channel weight presets (e.g. branch queries favor recency, project-level queries favor importance). Verbose memories receive a content-length penalty to keep results focused.

Storage

SQLite database at .claude/memory-db/memory.sqlite inside each project. Includes FTS5 and vec0 virtual tables for fast search.

Skills

| Skill | Description | |-------|-------------| | /memory-init | Bootstrap project memory from codebase files (README, package.json, git history, etc.) | | /memory-maintain | Deduplicate, consolidate, clean junk records, and split large memories |

claude-memory/
├── install.sh                    # Installer
├── server/src/
│   ├── index.ts                  # MCP server entry point
│   ├── cli.ts                    # Hook runner entry point
│   ├── database.ts               # SQLite + FTS5 + vec0
│   ├── memory.ts                 # 10 MCP tool handlers
│   ├── embeddings.ts             # Local embeddings (all-MiniLM-L6-v2, 384-dim)
│   ├── thresholds.ts             # Centralized similarity/scoring configuration
│   └── cli/
│       ├── session-start.ts      # Budget allocation, context injection
│       ├── session-end.ts        # Transcript analysis, memory creation
│       ├── error-context.ts      # Error pattern matching
│       ├── pattern-detector.ts   # Shared pattern clustering logic
│       └── transcript.ts         # Transcript parsing with noise filtering
├── skills/
│   ├── memory-init/              # /memory-init bootstrap skill
│   └── memory-maintain/          # /memory-maintain cleanup skill
├── agents/memory-curator.md      # Maintenance sub-agent
└── hooks/hooks.json.template     # Reference hook config

Tech Stack

TypeScript · MCP SDK · better-sqlite3 · sqlite-vec · @huggingface/transformers · Zod · tsup

Contributing

See CONTRIBUTING.md.

License

MIT