delx-memory

Local-first persistent memory MCP server. One shared SQLite store any MCP-speaking agent (Claude Desktop, Cursor, Hermes, OpenClaw, Codex) can read and write — so context survives across sessions AND across tools.

Why

Every chat client has its own ephemeral context. Quit the tab → preferences gone. Switch from Claude Desktop to Cursor → starting from scratch. Pin a side project in Hermes → invisible to the next agent.

delx-memory is a tiny MCP server that exposes a single shared SQLite file as a key/value memory layer. Any client that speaks MCP can read and write the same memory file → real continuity, real cross-tool context.

• 8 MCP tools — 4 read-only, 4 mutating.
• SQLite at ~/.delx-memory/db.sqlite (0700 dir, 0600 file).
• Secret-blocking: refuses to store credential-shaped keys or values.
• TTL support (lazy expiry on read).
• Tags + prefix filters + FTS5 full-text search (bm25 ranking, stemming, diacritic folding; LIKE fallback if FTS5 is unavailable).
• Mutations require explicit_user_intent: true so over-eager agents can't silently rewrite your context.
• Zero telemetry. Zero phone-home. The file is yours.

Install + run

# Run once (npx will download + boot)
npx -y delx-memory doctor

# Or install globally
npm install -g delx-memory
delx-memory doctor

The doctor command checks Node version, DB writability, and file permissions, then prints next steps.

Wire it into your MCP client

Claude Desktop

Add to ~/Library/Application Support/Claude/claude_desktop_config.json (macOS):

{
  "mcpServers": {
    "delx-memory": {
      "command": "npx",
      "args": ["-y", "delx-memory"]
    }
  }
}

Then restart Claude Desktop. See examples/claude-desktop.json.

Cursor

Add to ~/.cursor/mcp.json. See examples/cursor.json.

Hermes

See examples/hermes.md.

OpenClaw

See examples/openclaw.md.

Codex CLI

See examples/codex.toml.

The 8 tools

Reads (always safe — call without confirmation)

| Tool | Purpose | |---|---| | memory_stats | High-level: total keys, DB size, oldest entry, DB path. Start here on any session. | | memory_list | List keys (not values) with optional prefix or tag filter. | | memory_get | Exact key lookup. Returns value + timestamps + tags + metadata. | | memory_search | FTS5 full-text search across keys, values and tags — bm25 relevance ranking, stemming, diacritic folding, prefix matching; LIKE fallback if FTS5 is missing. Returns snippets. See the search quickstart. |

Mutations (require explicit_user_intent: true)

| Tool | Purpose | |---|---| | memory_set | Upsert a key. Rejects credential-shaped keys/values. | | memory_forget | Delete one key. Idempotent. | | memory_forget_by_tag | Bulk-delete every entry carrying a given tag. | | memory_export | Dump store as JSON / JSONL / Markdown, with optional since / until window. |

Every mutation refuses to run unless the caller passes explicit_user_intent: true. The intent: an agent that decides on its own to update memory must show its work. The user can see the flag in the tool call and reject it if they didn't ask.

Privacy contract (read this)

delx-memory is NOT a secrets manager. Use macOS Keychain / gnome-keyring / Windows Credential Manager for those.

What we refuse to store:

• Keys matching: oauth, token, secret, password, cookie, refresh, api_key, api-key, apikey, bearer, credential, session_id (case-insensitive).
• Values matching credential shapes:
  • JWT tokens (eyJ…)
  • Bearer <token> headers
  • Stripe sk_live_… / sk_test_…
  • Slack xoxb-… / xoxp-… / etc.
  • GitHub github_pat_… / ghp_… / gho_… / ghs_… / ghr_…
  • OpenAI / Anthropic sk-… (with realistic length)
  • AWS access keys AKIA…
  • Authorization: <scheme> <token> strings
• Nested objects are walked recursively — a nested field named refresh_token (even with an empty value) is rejected.

What stays local:

• The DB file lives at ~/.delx-memory/db.sqlite.
• Directory is created with mode 0700; file with mode 0600. (Best effort on Windows / WSL / non-POSIX filesystems.)
• Nothing is uploaded. No telemetry. No phone-home.

What we do NOT promise:

• Other users of the same machine (root, your sudo-using housemate) can read the file. Use full-disk encryption (FileVault, BitLocker, LUKS) if that matters.
• TTL is best-effort. Expired rows are deleted lazily on next read; SQLite doesn't VACUUM automatically, so freed pages may sit on disk. For sensitive ephemera, treat the DB file like any other unencrypted dotfile.
• No durability promise. Back up ~/.delx-memory/db.sqlite like any other dotfile if you care about losing it.

Example session

agent> memory_stats({})
→ { total_keys: 0, db_path: "/Users/me/.delx-memory/db.sqlite", … }

user> Remember that I prefer concise responses in pt-BR.

agent> memory_set({
  key: "user_preferences",
  value: { language: "pt-BR", verbosity: "concise" },
  tags: ["profile", "preferences"],
  explicit_user_intent: true
})
→ { action: "created", key: "user_preferences", … }

# … new chat, possibly different tool …

agent> memory_list({ tag: "preferences" })
→ [{ key: "user_preferences", updated_at: … }]

agent> memory_get({ key: "user_preferences" })
→ { found: true, value: { language: "pt-BR", verbosity: "concise" } }

Storage layout

| | | |---|---| | Default path | ~/.delx-memory/db.sqlite | | Override | DELX_MEMORY_PATH env var | | Directory mode | 0700 | | File mode | 0600 | | Schema | memory(key PRIMARY KEY, value, created_at, updated_at, ttl_expires_at, tags, metadata) | | Indexes | partial index on ttl_expires_at, plus tags, updated_at | | Per-value cap | 64 KB (JSON-serialized) | | Per-key cap | 512 chars |

CLI

delx-memory                Start MCP stdio server
delx-memory --http         Start local HTTP MCP server (127.0.0.1:3030)
delx-memory setup          Print MCP client config snippets
delx-memory setup --json   Print as JSON
delx-memory doctor         Health check + next steps
delx-memory doctor --json  Health check as JSON
delx-memory version        Print version

Environment

| Var | Default | Purpose | |---|---|---| | DELX_MEMORY_PATH | ~/.delx-memory/db.sqlite | DB file location | | DELX_MEMORY_TRANSPORT | stdio | stdio or http | | DELX_MEMORY_HOST | 127.0.0.1 | HTTP host | | DELX_MEMORY_PORT | 3030 | HTTP port | | DELX_MEMORY_ALLOWED_ORIGIN | http://HOST:PORT | CORS origin |

Development

git clone https://github.com/davidmosiah/delx-memory
cd delx-memory
npm install
npm test         # typecheck + build + smoke + secret-detector + ttl + tag-delete + metadata

See AGENTS.md for repo conventions, SECURITY.md for the security model and reporting policy, and CONTRIBUTING.md for PR rules.

License

MIT © 2026 David Batista