memshelf-mcp

Put your agent's memory on a shelf, hand it the index.

                              _          _  __
 _ __ ___   ___ _ __ ___  ___| |__   ___| |/ _|
| '_ ` _ \ / _ \ '_ ` _ \/ __| '_ \ / _ \ | |_
| | | | | |  __/ | | | | \__ \ | | |  __/ |  _|
|_| |_| |_|\___|_| |_| |_|___/_| |_|\___|_|_|
  ____________________________________________
 | INDEX >> | E-01 | E-02 | E-03 | E-04 | ... |
 |__________|______|______|______|______|_____|
        memory shelves for AI agents

What this is

Long-running agent sessions burn tokens re-sending history and lose detail to lossy auto-compaction. memshelf applies the docshelf pattern — tiny index in context, bodies fetched on demand — to the agent's own working memory:

1. Closed conversation topics, research dumps, and bulky tool output are offloaded to a local shelf as Markdown episodes.
2. Each episode carries an LLM-written, contract-validated digest that preserves decisions, rejected alternatives, artifacts, and open threads.
3. The agent keeps only INDEX.md (kilobytes) + digests in context and recalls exact sections via INDEX → episode → section slice over MCP.

Positioning in one sentence: claude-mem's loop, git's substrate, docshelf's navigation — episodic memory you can grep, diff, review, and carry between hosts. Private and local by default: the standard storage mode is a local git repo with no remote configured. The tool is public; the memory never is.

Measured, not promised

One week of dogfooding on the live shelf — full numbers and methodology in docs/demo.md:

Tokens are counted as chars/4 everywhere, so the ratios are estimator-independent; absolute counts move with the tokenizer.

Quick start

As an MCP server:

# Claude Code
claude mcp add memshelf -- uvx memshelf-mcp

// Claude Desktop (claude_desktop_config.json)
{
  "mcpServers": {
    "memshelf": { "command": "uvx", "args": ["memshelf-mcp"] }
  }
}

As a Claude Desktop extension — adapters/claude-desktop/: an .mcpb bundle installed from Settings → Extensions, with a Default shelf setting so calls need not repeat the path. Nothing has to be installed alongside it — not even Python.

As a Claude Code plugin — adapters/claude-code/: a /shelve skill plus SessionStart / SessionEnd / PreCompact hooks.

Or from the shell (pip install memshelf-mcp, Python ≥ 3.10) — the same loop, no MCP:

memshelf init   --shelf ~/my-shelf --name "My working memory"
memshelf shelve --shelf ~/my-shelf --slug 2026-07-23-topic --kind topic \
  --digest "What was decided, what was rejected and why, what stays open." \
  --section "Decisions=What was decided, and what was rejected instead — one line each."
memshelf recall --shelf ~/my-shelf --id 2026-07-23-topic --section Decisions --log
memshelf stats  --shelf ~/my-shelf   # claimed + realized savings
memshelf doctor --shelf ~/my-shelf   # exit 1 on integrity errors

Tool surface

One verb per job; the same names over MCP (memshelf_*) and in the CLI (long-form descriptions: docs/tools.md):

The rules the tools enforce

The digest is a contract, not a convention. It is the only thing read at recall before fetching a body, so a weak one devalues the whole episode. lint_digest runs the same validator as shelve with no side effects (--strict turns warnings into failures); errors block a shelve, warnings do not — a pure reference digest legitimately carries no decision marker. A rejected digest is a feature: the tool prints exactly what to fix and writes nothing.

--amend re-runs the whole pipeline — redaction, the digest contract, composition — so an amended episode is exactly as guarded as a fresh one, which a hand-edit of the file never is. Amending a slug that is not on the shelf is an error, not a create.

The episode is the source; everything else is output. ledger.tsv, INDEX.md, stats.svg and each category's .meta.json are derived: shelve writes and commits the episode alone, rebuild renders the rest — delete all four and rebuild restores them byte-identically. That is what makes two sessions shelving in parallel a non-event: the merge is clean by construction. On a shared shelf, let a bot own the derived files on main — ready-to-copy workflows in adapters/shelf-repo/; rebuild --adopt migrates an older shelf once, rebuild --check is the CI guard.

Two consequences worth stating plainly, because getting them wrong costs a merge conflict:

• doctor reports no-ledger-row and stale-index immediately after a correct shelve — on every branch, main included. Nothing is broken: the episode is written, the derived files are not rendered yet. They clear on the next rebuild — the bot's run, on a shelf that has one.
• Do not rebuild and commit the derived files by hand to silence them. That is exactly the conflict class the split removes: a hand-regenerated ledger.tsv/INDEX.md/stats.svg meets the bot's, and the merge stops being clean by construction. Wait for the renderer; on a shelf without a bot, run memshelf rebuild --shelf . as its own step.

If those warnings persist for a day while episodes keep arriving, that is a different state — the renderer is not lagging, it is stopped — and doctor says so separately, as derived-stale at error severity. The day is counted from when the renderer could first see the work, not from the ledger's last commit: an episode pushed minutes ago onto a shelf whose ledger has not moved since yesterday says nothing about the renderer, and saying otherwise sent readers to a manual rebuild, which is the conflict this whole split exists to avoid.

That arrival is read from this clone's reflog for the tracked upstream — the one local record of when the ref moved here. A commit date is not a substitute: it says when the episode was written, and «shelve now, push when confirmed» is a documented way to work, so the two can be a working day apart. Where the reflog cannot say — a fresh clone starts an empty one, which is what CI and ephemeral agent sessions run in — doctor reports renderer-wait-unknown at the unknown level instead of picking a verdict: from there, «stopped» and «handed the work a minute ago» look the same, and the renderer has to be judged where it can be observed, on its own job's run. On a shelf with no upstream there is no renderer to be fair to, and the ledger's own age stays the clock.

There was a third way to hold stale-index forever, and it is fixed rather than documented: docshelf split any episode past 50 KiB into section files beside it, shelve committed the episode alone, and from then on this working copy rendered an INDEX no other checkout could produce — no rebuild could clear it, and search answered with addresses that existed on one machine (#109). shelve no longer splits. A shelf that already carries such directories keeps reporting them as local-split-dir until memshelf prune-splits --shelf . --apply removes them; the episode file holds every section, so nothing is lost. It is a dry run without --apply, and a split directory that is committed is reported and left alone.