memory-core-mcp

Self-hosted MCP memory server for the Claude/agent stack, backed by an Oracle Autonomous Database 23ai (zmemory-adb) on the Stockholm Always-Free tier. Local-first, no cloud memory API, no vendor lock-in.

This is the "own MCP" core of the unified memory + connections platform:

• Memory substrate: Oracle 23ai native AI Vector Search (VECTOR(384)) — the functional equivalent of pgvector, but managed, auto-backed-up, mTLS-only, encrypted at rest.
• Embeddings: generated in-database via an ONNX model (DBMS_VECTOR), so no external embedding service is required. Until the model is loaded the server degrades gracefully to keyword search.
• Graph: typed links between memories (memory_links) mirror the vault's [[wikilinks]].

Architecture

Claude CLI / Desktop / agents
        │  (MCP: stdio local  |  streamable-http via CF tunnel)
        ▼
  memory-core-mcp  ──oracledb thin + mTLS wallet──►  zmemory-adb (Oracle 23ai)
        │                                              VECTOR + JSON + relational
        └── optional markdown mirror ──► ai-memory-vault (git)

zmemory-adb is a dedicated Always-Free Autonomous DB — it does not run on the constrained Ampere VMs (avm-01 Hermes / avm-02 n8n), keeping memory load off the compute boxes.

MCP tools

Tool	Purpose
memory_add	Persist a memory (capture/decision/fact/reference/project) + optional links
memory_search	Semantic search (cosine); keyword fallback if model unloaded
memory_get	Fetch one memory + its outgoing graph links
memory_recent	Most-recently updated memories (filterable)
memory_link	Create a typed edge between two memories (idempotent)
memory_stats	Counts by scope/kind; whether semantic search is active

Setup

uv venv .venv
uv pip install --python .venv/bin/python -e .

# 1. Provision DB (already done): Always-Free ADB 23ai 'zmemory-adb'
# 2. Wallet → ~/.secrets.d/zmemory-wallet  (oci db autonomous-database generate-wallet)
# 3. Bootstrap user + schema
./.venv/bin/python db/bootstrap.py
# 4. (optional, lights up semantic search) load ONNX embedding model
#    see db/03_embedding_model.sql

Config lives in .env (copy from .env.example, chmod 600). Secrets are in ~/.secrets.d/zmemory-adb.env — never committed and never written to the vault.

Run

./.venv/bin/memory-core-mcp           # stdio (local MCP client)
MCP_HTTP=1 ./.venv/bin/memory-core-mcp # streamable-http (multi-access via tunnel)

Security posture

• mTLS-only DB connection (wallet); no public DB listener.
• Least-privilege schema ZMEM (not ADMIN).
• Secrets in ~/.secrets.d/*.env (chmod 600), outside git.
• DB is Oracle-managed: automatic backups, patching, encryption at rest.