Mnemosyne

Mnemosyne Memory

You have persistent memory across sessions via Mnemosyne. Use it to avoid making the user repeat themselves and to recall past decisions, preferences, and project context.

When to Use

memory_recall — Call this FIRST when:

• The user references something from a past conversation ("remember when…", "like last time")
• You need to check if a preference or fact is already stored before asking
• Starting a new session in a project you've worked on before

memory_remember — Call this when:

• The user states a preference ("I prefer…", "always use…", "never do…")
• You learn a stable fact about the project, environment, or workflow
• A decision is made that should persist (architecture choice, convention adopted)
• You discover a tool quirk or workaround worth keeping

memory_forget — Call this when:

• A stored fact is stale, wrong, or superseded
• The user corrects something you previously stored

memory_sleep — Call this when:

• After a long session with many memories stored
• Memory recall feels stale or results seem outdated

memory_stats — Call this to check the state of the memory system.

Principles

1. Recall before asking. If the user might have already told you something, search memory first. Only ask if recall returns nothing relevant.

2. Store declarative facts, not instructions.

   • ✅ "User prefers concise responses"
   • ✅ "Project uses pytest with xdist, 4 workers"
   • ❌ "Always respond concisely"
   • ❌ "Run tests with pytest -n 4"

3. Importance matters. User preferences and corrections = 0.8+. Project facts = 0.5. Auto-captured session activity = 0.3. Reserve 0.9+ for identity-level facts (name, role, core workflow).

4. Don't store one-off task progress. "Fixed bug X", "submitted PR Y", "Phase N done" will be stale in a week. Use memory for things that still matter later.

5. The afterTool hook auto-captures file edits. You don't need to manually store "I edited file X" — that happens automatically. Focus your manual memory_remember calls on preferences, decisions, and facts.

MCP Server (Optional Advanced)

For the full Mnemosyne MCP surface (triples, graph traversal, scratchpad, sync, canonical facts, persona management), add the Mnemosyne MCP server to your Zero config:

{
  "mcp": {
    "servers": {
      "mnemosyne": {
        "type": "stdio",
        "command": "mnemosyne",
        "args": ["mcp"]
      }
    }
  }
}

This exposes the full Mnemosyne tool surface including mnemosyne_remember, mnemosyne_recall, mnemosyne_sleep, mnemosyne_triple_add, mnemosyne_graph_query, mnemosyne_scratchpad_*, and many more. The plugin's 5 shell-based tools cover the common case; the MCP server is for power users who want the full surface.