MemFS Search

A Letta Code mod package that adds an agent-callable memfs_search tool for searching the current agent's MemFS memory files.

The tool includes built-in keyword search over markdown memory files and optional QMD-backed semantic/hybrid search when qmd is installed and indexed.

Original source: https://tangled.org/cameron.stream/memfs-search

Install

letta install npm:@letta-ai/memfs-search

Run /reload in active sessions after installing.

Tool

• memfs_search searches this agent's local MemFS projection.

Actions:

• search (default) searches memory files.
• status reports memory path and QMD availability.

Search modes:

• keyword - built in, no dependencies.
• semantic - uses qmd structured vector search.
• hybrid - uses qmd structured lexical + vector search.

Example tool call:

{
  "action": "search",
  "query": "commit footer preferences",
  "mode": "keyword",
  "limit": 5
}

Status check:

{ "action": "status" }

QMD setup

semantic and hybrid modes require qmd to be installed and indexed. Install @tobilu/qmd, create a collection named memory over $MEMORY_DIR, and embed the memory markdown files.

If QMD is unavailable, use mode: "keyword".

Memory path detection

The mod first uses MEMORY_DIR when present. If not present in the mod runtime, it falls back to common local Letta memory paths using the current agent id:

• ~/.letta/lc-local-backend/memfs/<agent-id>/memory
• ~/.letta/agents/<agent-id>/memory

Safety

This is trusted local code. It reads markdown memory files from the current agent's local MemFS projection and returns matching snippets to the model.

If a mod breaks startup or command handling, recover with:

letta --no-mods
# or
LETTA_DISABLE_MODS=1 letta

See MOD.md for the agent-facing behavioral contract.