Bobs Big Brain Plugin

Bob's Big Brain — the plugin

The governed team brain — cited recall, hash-chained receipts. A local-first Claude Code + Cowork plugin: turn your own files into a governed, qmd://-cited brain with a tamper-evident, SHA-256 hash-chained audit trail. Compile, then govern. One plugin, two modes: local (default — in-process, no daemon, no runtime network after first-start provisioning, no API key for retrieval) or team (proxy to a shared governed brain over your network).

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📍 This product lives in two homes

| | Repo | What it is | |---|---|---| | Landing / thesis | intent-solutions-io/governed-second-brain | The umbrella — why this exists, the competitive teardown, the "Compile, Then Govern" thesis, the receipts argument. Start here for the story. | | The plugin (you are here) | jeremylongshore/bobs-big-brain-plugin | The installable code — the local stdio MCP server + skills. Start here to run it. |

It stacks on three engines:

| Engine | Repo | Layer | |---|---|---| | ICO | jeremylongshore/intentional-cognition-os | Compile — derive knowledge from a corpus (optional; the only part that egresses) | | INTKB | jeremylongshore/qmd-team-intent-kb | Govern — deterministic dedupe → policy → promote + the hash-chained audit | | qmd | tobi/qmd (@tobilu/qmd) | Retrieve — on-device search; every hit is a qmd:// citation |

This plugin bundles the compiled INTKB packages, so it runs the govern + retrieve loop fully in-process — the engines stay independent repos; nothing here forks or privatizes them.

Powered by tobi/qmd. We pin @tobilu/qmd and ride upstream via Dependabot — we do not fork the search engine. For the team index (not personal ~/.cache/qmd), operators on an INTKB checkout use ./scripts/bbb-qmd and pnpm search-canary (see qmd-team-intent-kb ops runbook).

What it does

Most "AI memory" gives an agent better recall. This does two things the category skips: it governs what's allowed to become durable memory (deterministic dedupe / policy / promotion — by code, not a model), and it ships a receipt — a qmd:// citation plus a SHA-256 hash-chained audit event — for every write. Runs on your machine; your files never leave it (retrieval is local; the optional ICO compile step is the only thing that egresses, and it's opt-in).

Tool surface

| Tool | Kind | What it does | |---|---|---| | brain_search | read | Cited search over your governed memory (qmd:// receipts), in-process | | brain_status | read | Counts by lifecycle state + category | | brain_audit_verify | read | Verify the audit trail — the SHA-256 hash chain and the external anchor log; flags any tamper | | brain_capture | write | Capture a fact as a governance proposal (to the local spool) | | brain_govern | write | Drain the spool → dedupe → policy → promote, with a hash-chained audit receipt — daemon-free | | brain_transition | write | Retire / re-lifecycle a memory (audited) |

Two skills front these: /brain (cited answers) and /brain-save (governed capture).

What the receipt does not do

Honesty is the point of a receipt. The chain gives you **tamper-detection — integrity + ordering, so an edited or reordered record is caught by verify. It is not** tamper-proof: on your own machine a writer with access can edit an event and re-hash the chain forward. Within a single trust boundary (your machine) that's exactly the integrity guarantee you want; cross-actor non-repudiation needs an external chain-head anchor (on the roadmap). It is not a blockchain and not immutable storage.

Independently verify the anchor log

brain_audit_verify is the in-box check — it runs inside the same codebase that wrote the chain (circular trust). For "don't trust us, run it yourself," there's a standalone, zero-dependency verifier that re-derives every anchor hash itself, importing nothing from this plugin or the engines. It's the cat log.md of receipts — one file, node built-ins only (crypto, fs, child_process), no build step:

# defaults to $HOME/.teamkb/audit/anchors.jsonl
node scripts/verify-anchors.mjs

# be explicit, and cross-check the live DB head against the latest anchor
node scripts/verify-anchors.mjs \
  --anchors "$HOME/.teamkb/audit/anchors.jsonl" \
  --audit-dir "$HOME/.teamkb/audit" \
  --db "$HOME/.teamkb/teamkb.db"

npm run verify-anchors        # same, via the package script
node scripts/verify-anchors.mjs --json   # machine-readable output

It checks four things against the external anchor log (anchors.jsonl, an append-only hash chain):

1. Per-record integrity — recomputes each anchorHash from the canonical body; any edit is an

ANCHOR_HASH_MISMATCH.

1. Chain linkage — record[0].prevAnchorHash is null, each subsequent prevAnchorHash equals

the prior record's anchorHash, and chainedRows never regresses.

1. External witness (git) — confirms the anchor log is committed and clean (an uncommitted or

un-pushed log is only locally witnessed — surfaced as a warning, not a hard fail).

1. Optional DB cross-check (--db, needs sqlite3 on PATH) — the latest anchor's chainHead

must equal the live audit chain's current head and its chainedRows must not exceed the current count, catching a silent rewrite of history the in-box chain-walk alone would miss.

Exit 0 on pass (witness-only warnings still exit 0); non-zero on any integrity, linkage, or history-rewrite failure. Run the verifier's own tests with npm run verify-anchors:test.

Install

Local-mode marketplace installs provision two lockfile-pinned native modules (better-sqlite3 and fs-ext) inside the plugin on first start. That one-time step uses npm; after it completes, local capture, governance, audit, and retrieval run in-process without a service daemon. Team mode does not load or install those local-store modules.

One command, two modes:

# A) zero-egress (default for regulated/client data) — nothing leaves the machine
npx governed-second-brain init  --index-only

# B) full compile — ICO derives knowledge (6 passes) before governing; opt-in egress to DeepSeek
DEEPSEEK_API_KEY=… npx governed-second-brain init 

It builds a governed, qmd://-cited, hash-chained-audited brain under ~/.teamkb, installs the native dep per-platform, and auto-registers the MCP server with Claude Code (claude mcp add; --no-register to skip). Full mode runs a loud pre-flight consent (your file text goes to DeepSeek; --yes to skip the prompt). Requires Node 20+, a C/C++ toolchain (for better-sqlite3), and qmd 2.x on PATH for retrieval.

After it finishes, start a new Claude Code session — the governed-brain tools are live. For the /brain and /brain-save skills too, claude plugin install governed-second-brain.

Team mode — point it at a shared brain

The same plugin runs in team mode when TEAMKB_API_URL is set: instead of an in-process local brain, it proxies to a shared governed-brain HTTP API (INTKB's apps/api) over your network — so a whole team queries and contributes to one governed brain. Set two environment variables:

• TEAMKB_API_URL — your team brain's API base (e.g. http://localhost:3847)
• TEAMKB_API_TOKEN — your personal bearer token (issued by the brain's operator)

You need network reachability to that API — typically a private network / VPN such as Tailscale (the brain is meant to stay off the public internet). The dispatcher auto-detects mode from TEAMKB_API_URL: set → team, unset → local. Same /brain + /brain-save skills either way.

Install it as a team member

The plugin runs in Claude Code or Cowork — the same install in both. It cannot run in claude.ai in a web browser or the phone apps (a browser tab can't reach a local plugin or a private network); Claude Desktop can, via a manual mcpServers config (see below). On macOS or Windows:

1. Join the team network (Tailscale) so your machine can reach the brain's API.
2. Add the plugin — in Claude Code or Cowork. It's a public repo, so no org membership or gh

login is needed: `` /plugin marketplace add jeremylongshore/bobs-big-brain-plugin /plugin install governed-second-brain@governed-second-brain ``

1. Save your connection to ~/.teamkb/team.json (Windows: %USERPROFILE%\.teamkb\team.json) at

mode 600. This file is read before shell env vars, so a Dock/GUI-launched Claude still reaches team mode: ``json { "apiUrl": "http://localhost:3847", "apiToken": "", "tenantId": "" } ``

1. Restart the app, then ask with keywords (retrieval is keyword-based, so strong words beat a

full sentence): /brain shipped this week. A cited qmd:// answer means you're connected.

macOS + Claude Code has a one-click installer that does steps 2–3 for you, and there's a full per-platform walkthrough (incl. the Claude Desktop mcpServers config) in [onboarding/](onboarding/README.md).

In team mode the tool surface is brain_search + brain_status (read), brain_capture (propose), and brain_inbox / brain_approve / brain_reject / brain_transition (admin review and lifecycle). Govern runs server-side, so there's no client brain_govern: the model proposes, the server disposes, and each promotion gets a hash-chained receipt. A member token can read + propose; admin actions return a clear 403 otherwise.

> Team mode is dependency-free — it uses only fetch + the MCP SDK, never the native store — so it > runs straight from a marketplace clone with zero build.

Build from source (to hack on the runtime)

pnpm -C ../qmd-team-intent-kb build   # the bundle inlines INTKB's compiled packages (sibling checkout, built)
pnpm install && pnpm build            # esbuild → plugin-runtime/governed-brain.cjs
node bin/init.mjs init  --index-only

Supply chain (shipped in 0.1.4): npm provenance (via the CI release workflow) and the gsb.lock.json reproducible pin — the exact ICO × INTKB × qmd × plugin tuple, verified by a hermetic full-chain CI smoke against the pinned set.

Coming: automatic Cowork MCP registration.

License

Apache-2.0. The umbrella and both engine repos are Apache-2.0; qmd (upstream) is MIT by its author, @tobi.

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Built by Jeremy Longshore · Intent Solutions · thesis at intent-solutions-io/governed-second-brain

Source & license

This open-source MCP server is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: jeremylongshore
• Source: jeremylongshore/bobs-big-brain-plugin
• License: Apache-2.0

Install and usage instructions live in the source repository linked above.