Memlord

Self-hosted MCP memory server with hybrid BM25 + semantic search, backed by PostgreSQL + pgvector.

Features

• Hybrid search — BM25 (full-text) + vector KNN (pgvector) fused via Reciprocal Rank Fusion
• Multi-user — each user sees only their own memories; workspaces for shared team knowledge
• 10 MCP tools — store, retrieve, recall, list, search by tag, get, update, delete, move, list workspaces
• Web UI — browse, search, edit and delete memories in the browser; export/import JSON
• OAuth 2.1 — full in-process authorization server, always enabled
• PostgreSQL — pgvector for embeddings, tsvector for full-text search

Quickstart

# Install dependencies
uv sync --dev

# Download ONNX model (~23 MB)
uv run python scripts/download_model.py

# Run migrations
alembic upgrade head

# Start the server
memlord

Open http://localhost:8000 for the Web UI. The MCP endpoint is at /mcp.

Docker

cp .env.example .env
docker compose up

Configuration

All settings use the MEMLORD_ prefix. See .env.example for the full list.

Variable	Default	Description
MEMLORD_DB_URL	postgresql+asyncpg://postgres:postgres@localhost/memlord	PostgreSQL connection URL
MEMLORD_PORT	8000	Server port
MEMLORD_BASE_URL	http://localhost:8000	Public URL for OAuth
MEMLORD_OAUTH_JWT_SECRET	memlord-dev-secret-please-change	JWT signing secret

OAuth is always enabled. Set MEMLORD_BASE_URL to your public URL and change MEMLORD_OAUTH_JWT_SECRET before deploying.

MCP Tools

Tool	Description
store_memory	Save a memory (idempotent per workspace by content)
retrieve_memory	Hybrid semantic + full-text search
recall_memory	Search by natural-language time expression
list_memories	Paginated list with type/tag filters
search_by_tag	AND/OR tag search
get_memory	Fetch a single memory by ID
update_memory	Update content, type, tags, or metadata by ID
delete_memory	Delete by ID
move_memory	Move a memory to a different workspace
list_workspaces	List workspaces you are a member of (including personal)

Workspace management (create, invite, join, leave) is handled via the Web UI.

Development

pyright src/           # type check
black .                # format
pytest                 # run tests
alembic-autogen-check  # verify migrations are up to date

License

Memlord is dual-licensed:

• AGPL-3.0 — free for open-source use. If you run a modified version as a network service, you must publish your source code.
• Commercial License — for proprietary or closed-source deployments. Contact sergey@memlord.com or dmitry@memlord.com to purchase.