MemPalace (cross-session memory for your sessions)

What it is

What it is

MemPalace is a cross-session memory system that gives every Claude Code session a set of MCP tools for remembering things you've done before. Your session transcripts are mined in the background and organized hierarchically into wings (broad areas like a project or topic), rooms (categories like prompts, responses, outcomes), and drawers (individual facts or snippets). Agents can search and add drawers via MCP tools, and you can browse/edit the same content yourself in the MemPalace page. Search is hybrid: semantic (via local 384-dim embeddings) plus full-text — neither needs a network call. Ships as an experimental feature; off by default.

Where to find it

Settings → Features → Enable Memory Palace turns it on. There is no panel of its own — it works by giving your sessions tools, so you see it in what an agent can recall rather than on a screen.

How it behaves

How to use it

1. Turn it on. Open Settings → Features → flip on Enable Memory Palace. The default is off. When you enable it, Omniscio writes a small curated .mcp.json to a private per-session path (under Omniscio's data dir, never your project folder) and hands it to each new session's Claude CLI via --mcp-config, so the session can see the MemPalace MCP tools.
2. Let sessions run normally. While sessions work, agents can call mempalace_search, mempalace_add_drawer, mempalace_list_wings, mempalace_list_rooms, mempalace_wake_up (returns an identity + essential-story preface), and mempalace_status (diagnostics). No action from you is required — the agent decides when to recall or store.
3. Browse what's been remembered. Once enabled, a Memory Palace entry (brain icon) appears in the top toolbar's "⋯" (more) menu, under Notes & capture — click it (or pin it to the toolbar) to open the three-pane UI: wings on the left, rooms in the middle-left, drawers in the middle-right. Arrow keys navigate, clicking a drawer reveals the content on the right. (It is NOT a left-sidebar hub. Agents and scripts can also open it over the CLI control server with POST /ui/open and body {"target":"mempalace"}.)
4. Search directly. The search bar at the top of the MemPalace page supports hybrid, semantic-only, or lexical-only modes. Use hybrid for best recall; semantic-only if you want concept matches; lexical-only if you need an exact phrase.
5. Mining runs after sessions end. You don't trigger it manually. The scheduler debounces per-session mining so a session that just stopped will be extracted into drawers shortly after, not during active work.
6. Turning it off. Flip the Enable Memory Palace toggle back off. New sessions will no longer load the MemPalace tools. Any session that was already launched (with its .mcp.json already on disk) is also covered: the MemPalace MCP server itself re-checks Omniscio's saved toggle every time it boots and exits cleanly when the feature is off, so a stale curated .mcp.json cannot resurrect the feature against your wish. As a tidy-up, the next spawn rewrites (or removes) that private per-session file.

For agents

How it works

The toggle mempalaceEnabled lives in /src/shared/types.ts and is wired through Settings → Advanced → Features at /src/renderer/src/features/settings/sections/features/feature-rows.tsx. When enabled, /src/main/services/mcp/mcp-entry.ts holds the shared bundled-local-MCP entry scaffold (it lived under mempalace/ as mcp-config-writer.ts until F145 moved it; MemPalace's own entry builder was retired with the rest of that set when MemPalace left composition on 2026-09-19) and still shapes any local entry the shared orchestrator writes into a session's curated .mcp.json — written to a private per-session path under Omniscio's data dir, never the workDir (see backend-spawn-contract.md §12) — pointing at the compiled server at out/mcp/mempalace-server.js. That server spawns via ELECTRON_RUN_AS_NODE=1 + process.execPath (Electron as pure Node) — which means any module it pulls in must defer top-level electron imports (e.g. /src/main/services/embedding-model.ts) or the subprocess crashes with Named export 'app' not found. The six MCP tools live in /src/main/services/mempalace-mcp-server/; storage and mining live in /src/main/services/mempalace/storage.ts, /src/main/services/mempalace/mining.ts, and /src/main/services/mempalace/mining-scheduler.ts. Drawers persist in SQLite (schema v87) across three tables: memory_drawers (content), drawer_embeddings (384-dim Float32 vectors from HuggingFace Xenova/all-MiniLM-L6-v2), and memory_drawers_fts (FTS5 with trigger-based sync). The UI is /src/renderer/src/features/mempalace/MemPalacePage.tsx backed by /src/renderer/src/stores/mempalace-store.ts. Full schema + tool signatures: MemPalace memory notes; full incident history: MemPalace memory-system postmortem.

Related

Related

• use-skills.md — Skills are a different way to teach agents: prompt-level recipes, not memory
• session-stuck-in-needs-you.md