cavemem — cross-agent persistent memory daemon

service Mon Jun 29 2026 00:00:00 GMT+0000 (Coordinated Universal Time) memorycavememclaude-codedaemonhooksagent-tooling

cavemem

Local-only persistent memory daemon for agent sessions. NOT the same as caveman (terse-prose rule) despite the name confusion.

What it is

npm package: cavemem (installed globally; latest verified 0.2.1 / 2026-06-29)
Install path on this machine: C:\Users\C5420321\AppData\Roaming\npm\node_modules\cavemem
Data dir: C:\Users\C5420321\.cavemem
Worker daemon: long-lived Node process, HTTP on 127.0.0.1:37777, PID in worker.pid
DB: SQLite at ~/.cavemem/data.db with FTS5 + local embeddings (Xenova/all-MiniLM-L6-v2)
Wired IDEs: claude-code (installed via cavemem install --ide claude-code)

What it stores

Every tool call observation: tool name + input + truncated output + session ID + timestamp. State at 2026-06-29: 3816 observations, 15 sessions, 24h worker uptime.

How Claude Code uses it

~/.claude/settings.json hooks block registers cavemem on five lifecycle events:

Event	What cavemem does
`SessionStart`	Loads recent session memories into prompt context
`UserPromptSubmit`	Snapshots the prompt for future recall
`PostToolUse`	Records the tool call observation
`Stop`	Flushes pending observations to db
`SessionEnd`	Marks session closed

Plus an MCP server (cavemem mcp) the agent can call for explicit memory_save / memory_search / memory_update / memory_delete / memory_list. That's where the memory tools listed in the Claude Code system prompt come from.

Why this exists (and why we kept it after the speed-stack rule "skipped" Caveman)

Speed-stack rule's "Caveman skipped — no install path" referred to the prose-compression Caveman from JuliusBrussee, which we did adopt as a written rule (rules/agent/caveman.md) without a CLI. cavemem is a different thing entirely — a memory daemon, no prose work. It IS installed and active, has been since pre-2026-06-29 sometime, and survives /clear / session restart unlike Claude's built-in memory.

Required peer dep

@xenova/transformers (~80 packages, ~100MB). Without it, FTS search still works but semantic search is dead with Cannot find package '@xenova/transformers'. Install:

npm install -g @xenova/transformers

Daily commands

cavemem status                       # show wiring, db size, worker state
cavemem doctor                       # health checks
cavemem search "query"               # CLI search (FTS + semantic)
cavemem search "query" --limit 5
cavemem viewer                       # browser UI at http://127.0.0.1:37777
cavemem worker start/stop/restart    # manage the daemon
cavemem export memories.jsonl        # backup
cavemem reindex                      # rebuild FTS if corrupted

Known pitfalls

sh not found in PATH breaks every hook silently. See runbooks/workflow/maintain/cavemem-hook-sh-not-found-fix.
Embedding model first-load = ~2 seconds. Cached after first call per process.
No card-on-file impact — fully local, no network calls outside 127.0.0.1.
Not in fleet parity matrix yet — only wired into Claude Code, not OpenCode/Kilo/Antigravity. Per agent-fleet-parity rule, either wire it everywhere or remove. Decision deferred — cavemem's install --ide only supports claude-code as of 0.2.1.

Cross-refs

runbooks/workflow/maintain/cavemem-hook-sh-not-found-fix — the gotcha that triggered this file
rules/agent/caveman — different thing, terse-prose rule, no relation despite the name