Reasonbook

Official registry AI and agents

Reasonbook: decisions that survive the session, in a local record AI agents keep.

Install

Add this to your client's MCP configuration (Claude Desktop: claude_desktop_config.json; Cursor: .cursor/mcp.json; VS Code and others use the same "mcpServers" shape).

NPM package @aquex/reasonbook
Claude Code
claude mcp add reasonbook -- npx -y @aquex/reasonbook@4.6.1
JSON configuration (Claude Desktop, Cursor, VS Code)
{
    "mcpServers": {
        "reasonbook": {
            "command": "npx",
            "args": [
                "-y",
                "@aquex/reasonbook@4.6.1"
            ]
        }
    }
}

Documentation

From the project's README on GitHub, refreshed weekly. Links open on GitHub.

Contents
  1. Reasonbook — decisions that survive the session
  2. Try it
  3. Codex plugins
  4. Existing installations and candidate testing
  5. Propose a decision, then approve it
  6. The method
  7. What leaves your machine
  8. What it is
  9. Install
  10. Configure your MCP client
  11. First call
  12. Tool surface
  13. Share a project's record
  14. Optional: hosted dashboard
  15. Project resolution
  16. Move work out of a central planning folder
  17. Environment variables
  18. Error response shape
  19. Safety
  20. Known limits
  21. Documentation
  22. Development
  23. License

Reasonbook — decisions that survive the session

Reasonbook keeps a local record of your project's decisions, reasons and lessons so the next agent session can pick up where you left off. You make the decisions; agents handle the bookkeeping. No dashboard account is required.

A 75-second replay of recorded runs. Read the demo's receipts and what Reasonbook sends and stores.

Try it

Choose a plugin below, or install the CLI with npm. Your first ten minutes takes you from installation to recording a choice and finding its reason in another session.

Commit the generated agent instructions, rbook/.gitignore and your project documents; keep the SQLite store, WAL/SHM files and snapshots out of Git.

Install it in Claude Code

Install the plugin once for all your projects:

claude plugin marketplace add kneelinghorse/reasonbook
claude plugin install reasonbook@reasonbook

Start a new Claude Code session after installation, then ask it to start a Reasonbook Ledger for this project. If the first session says Reasonbook is installing, start another once it finishes.

Get a project digest in three steps

Requires Node.js 20 or newer.

  1. Install the pinned CLI:

     npm install -g @aquex/reasonbook@4.5.1

    Ensure the global npm bin directory is on your PATH. If the former package is installed globally, run npm uninstall -g @aquex/cmos-mcp first. Version 4 provides only the reasonbook command; update scripts and MCP configurations that use the old command.

  2. In the project folder you want to track, start a Ledger:
     cd /absolute/path/to/your/project
     reasonbook init --level ledger
  3. Read its first digest:
     reasonbook review --format=context

The digest names this project and shows its decisions, lessons and open work. A new Ledger starts empty. Planner adds next steps; Builder adds sprints and missions.

Commit the generated AGENTS.md, CLAUDE.md, rbook/.gitignore and the project documents you maintain. A new record's ignore file keeps the SQLite store, its WAL/SHM files and snapshots out of Git. Init preserves an existing ignore file. Shared records require the store to remain untracked; exchange those records through Reasonbook's sharing commands.

A plugin installation does not put reasonbook on your terminal PATH. Plugin-only users can replace reasonbook in these commands with npx --prefer-offline -y @aquex/reasonbook@4.5.1, for example npx --prefer-offline -y @aquex/reasonbook@4.5.1 review --format=context.

Codex plugins

The developer plugin reasonbook supplies the server, seven skills and five lifecycle hooks. The conversation-focused reasonbook-chat supplies the same server and six distinct chat skills, with no hooks. Plugin loading, installation and project calls are verified in the bundled Codex CLI and app-server. ChatGPT Work remains unverified; this is not a hosted plugin for ChatGPT web or phone.

Install the developer plugin:

codex plugin marketplace add kneelinghorse/reasonbook
codex plugin add reasonbook@reasonbook

If the plugin is installed under its former name, remove it first, because both plugins answer as the same server: codex plugin remove cmos@cmos, and codex plugin remove cmos-chat@cmos for the chat plugin.

For chat workflows, install reasonbook-chat@reasonbook instead:

codex plugin add reasonbook-chat@reasonbook

For local development, replace the marketplace repository with this checkout's absolute path. Both plugins can be enabled together: Codex loads one server named rbook, and both sets of skills remain visible. Choose the developer plugin for building; choose the chat plugin for setup, catch-up, recall, proposing decisions, capturing notes and discussing next steps.

Node.js 20 or newer is required. The plugins install their exact Reasonbook version into ~/.config/rbook/plugins, with legacy config fallback for existing installations. On a first install, Reasonbook connects with an installing message; start a new session when installation finishes to load the project tools. The developer hooks share that runtime. The developer plugin requests forwarding of supported settings, including RBOOK_CONFIG_DIR; the portable chat plugin uses the environment inherited from its host. Use an absolute path, because empty or relative shared roots are refused. Environment forwarding depends on the client's plugin loader. If your loader does not forward a setting, use the default root or configure a manual server. See the harness guide.

In the Codex CLI, run /hooks and review the five developer-plugin commands once. If the desktop app does not expose that review, use its bundled Codex CLI with the same Codex home. Restart the app after installation if it has not loaded the plugin. A changed hook definition needs review again. The chat plugin has no hook review step.

Before replacing a CMOS 3.3.0 adapter, remove only its CMOS entries from project .codex/hooks.json and any user-level ~/.codex/hooks.json; keep unrelated hooks. Remove any other imported CMOS hook registration too. Keep one answering MCP server: remove a duplicate manual entry, or deliberately retain it and set "pluginServer": "off" in ~/.config/cmos-mcp/config.json (under your custom config root when using one).

Reasonbook uses the working folder supplied on each supported Codex call, so a conversation in a project can call rbook_review() without naming a path. Outside that folder, choose a registered address from rbook_project(action="list") and pass it as projectRoot, for example rbook_review(projectRoot="rbook://you/project"). Unknown or ambiguous addresses refuse; local-only projects need their folder. Tool hints conservatively include telemetry deletion, so Codex Auto mode can still ask for approval for any Reasonbook tool.

Existing installations and candidate testing

Reasonbook was formerly named CMOS. Upgrading from cmos@cmos? Uninstall it before refreshing the marketplace, using claude plugin uninstall cmos@cmos --scope user (or its original project or local scope), then install reasonbook@reasonbook. For a local installation, run the command from that project. If the marketplace already refreshed and uninstall says “not found”, use the tested recovery steps. Upgrade every client before moving an existing record.

For candidate testing, replace kneelinghorse/reasonbook with this checkout's absolute path. Start a new Claude Code session after installation. The plugin supplies the MCP server, hooks and commands; its first cold session may report that Reasonbook is installing and load the record from the next session. Use /reasonbook:init for a new record, /reasonbook:start to read it, /reasonbook:close-out to finish work, /reasonbook:plan to plan, and /reasonbook:build to execute. Plugin installation. Other tools use the harness adapters and coverage guide.

Propose a decision, then approve it

When a choice needs your approval, the agent ends its reply with one concrete line:

Would record: Use a weekly review because it keeps the reading list useful without daily upkeep.

With the developer hooks enabled and linked to that conversation, the Stop hook keeps this as a draft. Your next reply can approve it, decline it, ask a question or amend the wording. The agent records an approved draft with its returned P<n> id; a draft is not yet a decision. Inspect drafts from the project folder with:

reasonbook drafts list

reasonbook-chat asks for approval in the conversation and makes a direct record, preserving your observed words in its context. Reasonbook cannot independently verify that approval; it does not claim hook-verified approval for a chat-only record. An explicit approval already given for the exact wording counts, so the agent need not ask again.

The method

  • One project, one record of decisions, lessons, constraints and next steps.
  • Start from that record; supported hooks bring it into the session automatically.
  • Record decisions deliberately, with reasons. Supersede a changed decision.
  • Make expiry and supersession visible; closing a sprint keeps records active by default.
  • Keep the record with the project so it survives a change of tools.

The method gives the five lines in full, what Reasonbook does at each level, and how to move up; the starter templates hold the files each level starts with.

What leaves your machine

The record stays in your project's SQLite file. With a stored user-scoped key or legacy environment credentials, explicit session and sprint closes attempt a background upload of the whole file, including pending and declined proposals. For a registered project, MCP tool writes also schedule an upload after 5 quiet minutes or 30 minutes of continuous writes; the next poll starts it within 60 seconds when no upload lease or failure backoff blocks it. Transfer time follows. See the timing and failure details under Optional: hosted dashboard. RBOOK_CHECKPOINT_SYNC=off stops automatic uploads and manual rbook_db(action="backfill") uploads. Other requested network actions and shared-record exchanges remain available. Logging out leaves project keys valid for other requested dashboard calls, but closes and manual backfill also require a stored user-scoped key or environment credentials. Implicit process-exit closes do not upload. A project shared through reasonbook.ai keeps uploading its whole file until the share hands its record to the dashboard's referee copy, then sends the shared record's changes until it is moved back. The client also supports a member uploading a scrubbed SQLite copy when the dashboard requests hosted recovery; that route is not deployed on reasonbook.ai. Either RBOOK_SHARED_SYNC=off or RBOOK_DASHBOARD_SHARING=off stops recovery contributions, including during an explicit sync. Full network and data disclosure.

What it is

Reasonbook is the protocol + client. It runs locally on your machine, owns a SQLite database under rbook/db/rbook.sqlite, and exposes 15 typed tools over MCP. Claude Code and Codex are verified (see the harness guide); other MCP clients, such as Claude Desktop, Cursor, Zed, VS Code and Windsurf, are untested.

Out of the box you get:

  • Sprint and mission state machines with auditable transitions
  • Session capture for decisions, learnings, constraints, next-steps
  • Strategic context that condenses across sprints, with FTS5 retrieval
  • Full-text search across decisions, learnings, missions, sessions
  • Database snapshots on demand; backup attempts around sprint closes; required backups before a restore or a snapshot prune with selected rows
  • Per-project credential store and device-code auth (RFC 8628)

The dashboard at reasonbook.ai is optional. You can run Reasonbook standalone forever — sign-up unlocks dashboard uploads (SQLite → Postgres mirror), the project registry (rbook://you/* addresses), and cross-project messaging. Without it, every other tool still works locally.

Install

Recommended: a global install of this release. The server then starts from disk, with no registry lookup on launch:

npm install -g @aquex/reasonbook@4.5.1

If the former package is installed globally, run npm uninstall -g @aquex/cmos-mcp first. Version 4 provides only the reasonbook command; update scripts and MCP configurations that use the old command.

Or run it on demand with npx. Pin the version and prefer the local cache: an unpinned npx -y can look the package up again on every launch.

npx --prefer-offline -y @aquex/reasonbook@4.5.1

Semantic (vector) search is optional. Without it, retrieval is keyword-only, and the install is about 45 MB instead of about 306 MB. To add a vector term to retrieval, install @xenova/transformers next to Reasonbook. rbook_db(action="health") reports whether it is on.

Requires Node.js 20 or newer.

Configure your MCP client

Claude Code and Codex are verified; the other blocks follow each client's own MCP configuration and are untested with Reasonbook. Each example below runs a pinned version through npx, preferring the local cache; to upgrade, change the version. With the global install, use "command": "reasonbook" and drop the npx arguments (keep --project-root where an example has it).

Claude Code
claude mcp add-json rbook '{"command":"npx","args":["--prefer-offline","-y","@aquex/reasonbook@4.5.1"]}'
Claude Desktop

Add to ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or the equivalent on Windows/Linux:

{
  "mcpServers": {
    "rbook": {
      "command": "npx",
      "args": [
        "--prefer-offline",
        "-y",
        "@aquex/reasonbook@4.5.1",
        "--project-root",
        "/absolute/path/to/your/project"
      ]
    }
  }
}

Claude Desktop is expected to start servers with no project context (on macOS, from / with no workspace roots; untested with Reasonbook), so name the project in the config. --project-root applies only to this server entry, and only to calls with no project context: no projectRoot, no workspace roots, and a working directory of /, your home directory or the server's install directory. A client that starts the server from any other folder should pass projectRoot instead.

Cursor

Add to ~/.cursor/mcp.json:

{
  "mcpServers": {
    "rbook": {
      "command": "npx",
      "args": ["--prefer-offline", "-y", "@aquex/reasonbook@4.5.1"]
    }
  }
}
Zed
{
  "context_servers": {
    "rbook": {
      "command": "npx",
      "args": ["--prefer-offline", "-y", "@aquex/reasonbook@4.5.1"]
    }
  }
}
VS Code (Claude extension)

Use the Claude Code command above from the integrated terminal, or add the server through /mcp in the Claude panel. The extension and CLI share MCP configuration; start a new conversation after changing it. The extension does not add claude to your terminal PATH, so the terminal route needs the standalone Claude CLI. Claude Code in VS Code

Windsurf
{
  "mcpServers": {
    "rbook": {
      "command": "npx",
      "args": ["--prefer-offline", "-y", "@aquex/reasonbook@4.5.1"]
    }
  }
}

First call

Project tools work on a folder that has a Reasonbook database, so a new project starts with init:

rbook_project(action="init", projectRoot="/absolute/path/to/your/project")

init creates rbook/db/rbook.sqlite, the seed files, an AGENTS.md and a CLAUDE.md that imports it at the project root (keeping either file if it already exists). In a folder without that database, the tools that read or write a project refuse and name init; registry and sign-in actions need no project.

Then run rbook_agent_onboard once: on a new project it walks the first-session setup. Open every later session with the session digest:

Run rbook_review to see the project state.

rbook_review returns the shared session digest: project identity, current sprint, open work and recent decisions. Its local text core is capped at 4,000 characters; appended portfolio context and the surrounding MCP response are outside that cap.

The full walkthrough — install → config → init → first sprint/mission/session loop — lives in docs/getting-started.md.

Tool surface

Reasonbook exposes 15 consolidated tools. 12 use an action parameter to select the operation; rbook_agent_onboard, rbook_status and rbook_review take no action. TOOL_REFERENCE.md publishes one parameter table per action, so it says which parameters actually apply to a given call.

ToolPurpose
rbook_reviewSession digest: identity, sprint, work, decisions, other projects' signals
rbook_agent_onboardCold-start payload: identity, active sprint, missions, decisions, suggestions
rbook_statusDiagnostic snapshot: rbook_address, dashboard_url, auth_tier, sync timestamps
rbook_missionMissions — create, update, query, and link dependencies
rbook_mission_transitionMission state machine — start, complete, block, unblock, drop, defer
rbook_sprintSprints — CRUD, closeout, retro, and cross-sprint analytics
rbook_sessionWork sessions (optional) — start, capture insights, complete, list, search
rbook_contextMaster/project context — view, update, condense, snapshot, and search
rbook_decisionsStrategic decisions — record, show, list, search, update, staleness review
rbook_learningsCross-cutting learnings — list, search, show, update, and reaffirm
rbook_dbDatabase ops — health, snapshot/restore, backfill, and a context-snapshot prune
rbook_projectProjects — init, register, list, validate; share, invite, join, members, sync
rbook_authDashboard credential lifecycle — device-code login, rotate, revoke
rbook_messageCross-project messaging (requires the hosted dashboard)
rbook_feedbackAgent-feedback channel — list, triage, resolve, archive

See TOOL_REFERENCE.md for the exact per-action parameter reference — it is generated from the tool definitions on every build, so it never drifts from the shipped surface.

Share a project's record

The owner can share a project with editors. Each keeps a full local copy, works locally, and exchanges changes either through reasonbook.ai, which keeps the project's referee copy and shows it on the dashboard, or directly through the owner's copy over SSH or with bundles carried by hand. Conflicting field values stay visible until someone settles them.

Sharing is supported in the measured setup: two accounts operated by one person, on two machines, either through reasonbook.ai or in an owner/member star over SSH. A second person's collaboration and privacy experience remain unvalidated. Editors' rows become local project content for the owner's agents, without a foreign-source fence; invite people whose record content you trust.

Through reasonbook.ai, each person signs in on their machine. The owner's agent shares the project, the owner shares it with the editor on the dashboard, and the editor gives their agent the join sentence from the project's page. The owner's copy can move the project back with rbook_project(action="move", to="owner") or reasonbook move --to owner, then catch a member's copy up over SSH, and the member confirms the move with reasonbook sync --confirm-owner. That was measured live with one member present, the move made through rbook_project. One machine keeps one live copy of a shared project.

Start with the sharing steps and trust boundary. Sharing over SSH needs no dashboard account. Automatic exchanges run at session start and end where hooks run, and every five minutes for shared projects the server has opened with a saved route. RBOOK_SHARED_SYNC=off stops those automatic exchanges; explicit sync and bundle commands remain available.

Optional: hosted dashboard

The dashboard is a separate service. Sign up at reasonbook.ai to unlock:

  • Dashboard mirror — uploads a snapshot of your whole SQLite file for the dashboard to display.
  • Project registry — addressable rbook://you/project-name URIs across machines.
  • Messaging — rbook_message(action="send") between your own projects.
  • Sharing — share a project's record with editors, who join from its page; the dashboard keeps the referee copy and shows the record, its members and a feed of what each created and moved. See Share a project's record.

To connect:

export RBOOK_DASHBOARD_URL=https://reasonbook.ai

Then run rbook_auth(action="login_init") from your agent. It returns a one-time userCode and verificationUri — paste the code at the URL in your browser, then run rbook_auth(action="login_complete", deviceCode=...) to finish. Credentials persist atomically to ~/.config/rbook/credentials.json (mode 0600).

RBOOK_DASHBOARD_URL defaults to https://reasonbook.ai. Without a dashboard credential, dashboard operations return a structured DASHBOARD_NOT_CONFIGURED error that names rbook_auth(action="login_init"). Local tools and direct shared-record exchanges work without the dashboard.

With a stored user-scoped dashboard key or legacy environment credentials, explicit rbook_session(action="complete") and rbook_sprint(action="complete") calls attempt a background upload and may register the project first. For a registered project, an MCP tool call that actually writes its store also schedules an upload. It becomes due after 5 quiet minutes or 30 minutes of continuous writes, and starts within the next 60 seconds when no upload lease or failure backoff blocks it. A running server must have opened the project; work owed by a short-lived process survives for the next server. Each upload sends a consistent snapshot of the whole SQLite file, including pending, declined and expired proposals. Transfer time is additional, and concurrent servers share one upload lease per project.

Upload results and failures appear in rbook_status and rbook_review. Transient failures back off for 1, 5, 15 and then 60 minutes, never earlier than Retry-After. Authentication failures are rechecked before pausing; hourly probes can resume uploads when the key works again. Confirmed deletion or replacement holds this project’s automatic uploads, closes and manual backfill. Other projects keep uploading. Tier and confirmed forbidden responses remain paused until a successful explicit attempt. Close receipts name the upload status and any hold. A server ending after an explicit close drains its accepted upload within a bound; an interrupted upload remains owed for the next server. A failed upload does not fail the local write or close. Implicit process-exit closes do not upload. Set RBOOK_CHECKPOINT_SYNC=off in the server environment to disable automatic uploads and manual backfill; it does not disable explicit sync, messaging, sign-in or shared-record exchanges. Logging out revokes a user-scoped key, leaving project keys valid for requested dashboard calls. See SECURITY.md.

Project resolution

Reasonbook never acts on a project you did not name. For each tool call it picks one project, in this order, and refuses rather than falling back when that project cannot be used:

  1. The projectRoot parameter on the call: a project folder or an exact registered rbook://owner/project address. Address discovery reads stored identities without repairing them; no match, duplicate matches or an unreadable registered identity refuse.
  2. For a supported Codex request, its conversation working folder. An invalid supplied folder refuses instead of falling back to the server's folder.
  3. The workspace roots your MCP client advertises: the first one inside a Reasonbook project.
  4. The working directory, or the nearest folder above it that is a Reasonbook project — one holding rbook/db/; a plain folder named rbook does not count (the search stops below your home directory).
  5. Only when the server has no project context at all — no projectRoot, no roots, and a working directory of /, your home directory or the server's install directory (as for a client that starts servers without a project folder): the --project-root <dir> argument in that server's config, then a registry default set with rbook_project(action="register", projectRoot="...", setAsDefault=true).
  6. Otherwise the call is refused. In a folder that is not a Reasonbook project, a write names rbook_project(action="init") and a read answers "No Reasonbook project in '<dir>'".

rbook_project(action="list") includes stored ids, addresses and folders. init, register and unregister require folders; an address never becomes a filesystem path.

Every successful response names the project it used (projectRoot and resolvedBy in its data), and says so in its text whenever the project came from workspace roots, --project-root or the registry default. A registry default set before 3.2.0 is not applied until you re-run setAsDefault; the server, rbook_message(action="whoami") and rbook_review say so when one exists.

Move work out of a central planning folder

If you collect several efforts in one Reasonbook project, use spin-out when an effort needs its own project folder. It copies selected missions, their linked decisions, learnings and next steps, and any additional record IDs you name. The source remains a readable history with pointers to the new project.

Create the destination folder first. The source must be registered, and the two stores must have distinct project identities. Both roots are required; this command does not use an ambient project or registry default. Omit --apply to preview the selection and mapping:

reasonbook spin-out --from /work/projects --to /work/new-product --sprint sprint-12

# Or select missions, with additional decisions, learnings and next steps by ID:
reasonbook spin-out --from /work/projects --to /work/new-product \
  --missions product-plan,product-prototype \
  --decisions 41,42 --learnings 17 --next-steps 23,24

# Apply the same reviewed selection:
reasonbook spin-out --from /work/projects --to /work/new-product \
  --missions product-plan,product-prototype \
  --decisions 41,42 --learnings 17 --next-steps 23,24 --apply

Choose either --sprint or --missions. A destination without Reasonbook is reported as needing initialization in the preview; --apply initializes it and takes database backups before copying. Copied work retains its status but has no sprint assignment in the destination. Assign it to a target sprint when ready. Source Queued, Blocked and Deferred missions become Dropped; Completed and already Dropped missions retain their status. Source decisions and learnings become archived, and source next steps become dropped. Default lists and retrieval omit these transferred source rows. Sprint history retains its counts and identifies transfers with their destination pointers. No sprint closes automatically.

Read a source or copied decision, learning or mission with its existing show action and an explicit projectRoot; the result includes spunOutTo or spinOutOrigin and a readable address. For a historical next step, use rbook_context(action="next_steps", nextStepAction="list", nextStepIds=[23], projectRoot="/work/projects"). Explicit IDs include moved or dropped rows; an explicit nextStepStatus still filters them. The ordinary next-step list continues to show open work. Target next steps without a sprint are flagged idle after 42 days. The CLI does not upload either store immediately: each enters the normal upload schedule after its next successful MCP write, subject to the configured upload controls.

Retry the exact command after an interruption. A verified completed operation returns unchanged. If source records changed after the target copy committed, final source marking is refused and both stores are preserved for review. If a reserved retry lacks its committed target receipt, the command also refuses: it cannot distinguish a crash before copying from an erased proof of an earlier copy. Preserve both roots and the operation ID named in the remedy, inspect their ledgers and pre-write snapshots, and resolve or restore the conflicting state before retrying. Do not delete a reservation to force another copy; retries never silently overwrite copied work.

Environment variables

# Optional — connects to the hosted dashboard. Defaults to https://reasonbook.ai
# when unset; treat empty string as unset.
RBOOK_DASHBOARD_URL=https://reasonbook.ai

# Optional — the directory the server reads its own .env from. It does NOT select a project:
# use the projectRoot parameter, or --project-root in a server's config.
RBOOK_PROJECT_ROOT=/path/to/your/project

# Optional — override the credential + registry directory. Default: ~/.config/rbook
RBOOK_CONFIG_DIR=/custom/path

# Snapshot retention (default shown)
RBOOK_MAX_SNAPSHOTS=50

# Optional — disable timed uploads, explicit-close uploads and manual backfill for this server.
# Shared-record exchanges and other requested network actions remain available.
RBOOK_CHECKPOINT_SYNC=off

# Optional — disable shared-record exchanges started by hooks and the server timer.
# Explicit reasonbook sync and bundle commands remain available; recovery contributions stop.
RBOOK_SHARED_SYNC=off

# Optional — turn off starting a share or a join through reasonbook.ai on this machine
# (off, false, 0 or no, in any case). On by default; a project already shared through the
# dashboard syncs either way. Hosted recovery contributions are also stopped by this switch.
RBOOK_DASHBOARD_SHARING=off

Error response shape

Every tool returns a uniform envelope:

{
  "success": false,
  "error": {
    "code": "MISSION_NOT_FOUND",
    "message": "Mission 's99-m01' not found",
    "suggestion": "Use rbook_mission(action=\"list\") to see available missions"
  }
}

code is machine-readable, message is human-readable, suggestion is a concrete next step. Validation errors carry validValues (a string[]). State errors can carry currentState: generally a status string when the relevant mission, session, or sprint state is available, and — on SESSION_ALREADY_ACTIVE only — an object { id, type, title, startedAt, captureCount }. Branch on code before reading it.

Safety

  • Append-only audit. Session events and mission transitions are append-only rows. Context snapshots keep their rows, ids and events, but rbook_db(action="prune_snapshots") can empty the content of copies Reasonbook wrote on its own.
  • Atomic credential writes. credentials.json is written via temp-file + rename with 0600 permissions.
  • Database snapshots. rbook_db(action="snapshot") copies the database on demand. A rbook_sprint(action="complete") attempts a snapshot before and after the close; a snapshot failure warns without blocking completion. Applying rbook_db(action="prune_snapshots") to a nonempty selection requires a backup, and rbook_db(action="restore") first copies the live database to rbook/db/snapshots/pre-restore/. RBOOK_MAX_SNAPSHOTS caps how many are kept: taking one deletes the oldest beyond it, automatic ones included. Nothing else snapshots first, and there is no soft-delete net — rbook_db(action="purge") deletes this project's data from the dashboard mirror, and is refused while a project is shared through reasonbook.ai. See SECURITY.md.
  • Dry-run where it exists. rbook_context(action="condense") accepts dryRun to preview without committing. It is not a general property of mutating tools. Backfill's old event-replay dry run is retired and refuses with LEGACY_SYNC_RETIRED.

Known limits

  • Shared records switch to protocol 2 only after every active copy reports support; rbook_review names blocking copies. Before the switch, id claims use their existing clock order. Afterwards, the first counted acceptance fixes a claim's position, pre-switch claims outrank later ones, and an accepted id is final once the copy holds every earlier-positioned claim's data. A predictable id can still be claimed first; recovery judges previously unjudged transactions in clock order. A gone copy must be set aside to stop blocking the switch. On reasonbook.ai, its owner page needs the host's set-aside deployment to offer that operation.
  • After a protocol-2 switch, older readers receive each stream only before the whole transaction containing its first protocol-2 change. Joins, successors and planned moves to old or unreported readers refuse. Downgrading can rename ids locally: the old copy still sends its own writes but receives nothing past that boundary; an old authority holds members' protocol-2 writes. Upgrade every copy before continuing shared work. Recovery keeps the switch only when it is in the adopted authority prefix.
  • Registered projects with dashboard credentials upload snapshots after writes and explicit closes while a server is running; manual rbook_db(action="backfill") requests a whole-file upload immediately. Shared-record exchanges use their own hooks, timer and RBOOK_SHARED_SYNC control.
  • SQLite is the source of truth; the dashboard holds the owner's uploaded mirror. Shared copies exchange their record with reasonbook sync, through reasonbook.ai, over SSH or by bundle.
  • Through reasonbook.ai, moving a project back was measured with one member and automatic syncs off: the owner's copy caught the member's copy up over SSH before that copy had synced with the dashboard since the move. With automatic syncs on, the member's copy may well sync first. Not measured: a member's copy that syncs with the dashboard first, whose sync then says to sync with the owner's copy over SSH or with a bundle, and a member's copy the owner's machine cannot reach over SSH. The dashboard's activity feed shows 50 entries a page by default and at most 100, and its decisions page 20 decisions a page; older entries are on later pages.
  • A project shared through reasonbook.ai changes through its members' agents; the dashboard's pages show the record. The referee library supports recovery from surviving copies and re-sharing after a move back with retained member/account bindings. These require the dashboard's matching routes, stored history and owner controls to be deployed. Until then, a lost hosted copy still stops hosted sharing, and a re-share cannot safely restore its members through the older host. Every member keeps their local copy.
  • A share through reasonbook.ai names and refuses over the owner's other copies that wrote, exchanged successfully or retain an SSH route, including an observed or routed former owner copy. Dashboard-route rows, cut copies and this folder's former identities do not count. On the direct authority copy, reasonbook set-aside --replica <id> previews one gone copy's held cutoff and last exchange; add --yes to record it. The person's other copies remain members. Role changes, removal and re-admission preserve the cut; later writes stay quarantined for the person to redo, and recovery does not wait for that copy. On a hosted project, the referee library provides the dashboard-only setAside operation, with explicit confirmation for a copy that called in the last seven days; reasonbook.ai must deploy that operation before its owner page can offer it. Local administration is refused while the dashboard referees.
  • A record with a set-aside requires a reported library version of 4.5.0 or later at the target of a planned handover or dashboard share. Unknown reports refuse too; a share checks before uploading. A reasonbook recover run by a pre-4.5.0 binary can undo a set-aside. Upgrade recovery copies before using them. The old rbook_db(action="clone") and rbook_db(action="pull") actions refuse with LEGACY_SYNC_RETIRED; their action values remain until 5.0.0.

Documentation

  • Documentation home — what it is, how to install it, the levels and where to read more.
  • The handoff demo — a 75-second replay of recorded runs, with a transcript.
  • Trust — what leaves your machine, what the hooks read, and how to turn each part off.
  • Privacy — collection, dashboard visibility, retention and removal.
  • The method — the five lines, the three levels and how to move up.
  • Getting started — client configuration and an optional Builder walkthrough.
  • Harness coverage — native adapters, MCP prompts and the fallback without hooks.
  • Tool reference — every tool, action, and parameter (generated from the tool definitions).
  • Changelog — release notes and tool-surface changes.

Development

git clone https://github.com/kneelinghorse/reasonbook
cd reasonbook
npm install
npm run build
npm test

Development needs Node.js 20.17 or newer (lint-staged 16.4); the published package runs on Node.js 20 or newer.

Pre-commit hooks run lint + format via husky/lint-staged. This public repository is a code mirror; release validation and npm publishing run from the private source.

License

Apache-2.0. See LICENSE and NOTICE.

Frequently asked questions

What is Reasonbook?

Reasonbook: decisions that survive the session, in a local record AI agents keep.

How do I install Reasonbook?

It runs on your machine. In Claude Code: claude mcp add reasonbook -- npx -y @aquex/reasonbook@4.6.1. For other clients, paste the JSON configuration from this page into their MCP settings.

Does Reasonbook need an API key?

Its registry entry lists no required key or secret. Some features may still need an account with the service it connects to.

Is Reasonbook open source?

Yes. Its code is on GitHub under the Apache-2.0 license.

Who maintains Reasonbook?

It is published by kneelinghorse. AI.tn lists it but does not maintain or endorse it.

From the official MCP Registry. Listing is not an endorsement: review a server's code and permissions before giving it access to your data.