One word for each thing, defined once.
The site, the docs and the code use the same words. Here are the ones that name a part of instibrain, in seven groups, each with a link to the page where it does its work.
What a brain is made of.
The brain, its spaces and pages, who reads them, and what they said before.
- brain
Every space a person reads, as one whole: their Personal and Sealed, the team spaces of their account, and any space opened for a few people. It is served to the sync client over HTTP and, for its open spaces, to AIs over MCP.
on /brain- space
A set of markdown pages in folders, shared whole with one set of people: no folder inside it is shared on its own. Pages only some people should read go in a space of their own. A space is open or sealed, and belongs to a person or to the account.
on /brain- personal space
A space a person owns, born with a grant to them alone; its grants, not its kind, decide who reads it. Every person has two from their first sign-in: Personal, open, and Sealed, sealed.
on /spaces/personal- team space
A space the account owns, which only an owner or admin opens. Its managers read its history, and the account is its content owner, so an owner or admin names who else recovers it.
on /spaces/team- page
One unit of memory: a path, a body in markdown, and a version vector. The first heading is its title.
on /brain- folder
A path inside a space. A folder exists through the pages in it, and it is shared as its space is.
on /brain- reader
The read-only role, the first of three: a reader reads a space, an editor also writes it, and a manager also decides who it is shared with. Each person, group, or agent a space is shared with holds one, and it covers every page.
on /brain- recovery grant
A person's right to read what a space said before: old versions, the version list, removed pages, and the changes feed, under a path. A manager of the space holds it for the whole space, by the role; the content owner names anyone else who holds it, and it lasts only while that person reads the space.
on /spaces- review
Where a restored page waits, read by its person alone, until they check who reads the space and publish it as the page's next version. No restore goes live without one.
on /spaces- cockpit
Where a person sees the brain, at my.instibrain.ai: its spaces and who each is shared with, its specialists, every page, what waits for them, the log of which AI or agent wrote what, and the read trail.
on /markdown-editor- read trail
Every page read of a space, kept 30 days: who read it, through which computer, AI, agent, or the cockpit, and when. The space's managers see every row and anyone else their own; no AI reads it. One caller opening many pages within ten minutes is mailed to the managers.
on /security- inbox
The page Personal starts with, inbox.md. A line or half a thought goes in from any surface, and leaves only by becoming a page of its own or by deletion.
on /spaces/personal- surface
Anywhere a person or an AI reaches a brain from: a computer running the sync client, Claude on the web or on a phone.
on the landing page
Who signs in, and who runs what.
An account holds its people, and an account role runs it without opening a page.
- account
Who owns the team spaces: a company, a team, or one person. Its people, and the people it invites, see the display name its owner sets in Settings.
on /spaces/team- identity
Someone who signs in: one email and one password. One identity can be in several accounts, and the cockpit switches between them.
on /get-started- person
An identity in one account, with the name, role, and picture that account sees. The brain knows a person by this id, so a space can be shared with someone invited before they join.
on /spaces/team- account role
Owner, admin, or member. Owners and admins run the account: its people, its groups, and its team spaces. An account role opens no page.
on /spaces/team- administrator
Our staff, apart from customers: a sign-in of their own on the internal cockpit, management.instibrain.ai. An administrator's login opens no account and no brain, and every change they make there stays on the staff trail for a year.
on /privacy- paused account
An account our staff stopped for now. Nobody signs in to it and its devices and agents are refused, but nothing is ended.
on /terms- invite
A one-time link to join an account, valid seven days, mailed or handed over. A new address chooses a password with it; an address that signs in already joins with the one it has.
on /get-started- group, and Everyone
People of one account under one name; a space or a specialist shared with it reaches them all. Everyone is the group every account has: it holds every person of the account.
on /spaces
How a space keeps its shape.
The files that say how to work in a space, the tools that hold it to them, and the scripts it carries.
- template
The files a space starts with. A new space starts from empty: its CLAUDE.md, which says its purpose, and its index. Each person's Personal and Sealed start from their own templates.
on /spaces- skeleton
The few files that say what a space is and how to work in it: its CLAUDE.md, its index, and the index file of each top-level folder. Only a manager of the space changes, moves, or removes one.
on /for-agents- index file
The file that says what a folder holds and how to add to it, such as _index.md or README.md. Its first sentence is the folder's purpose.
on /spaces- structure tools
The MCP tools that give an AI a space's map and skeleton and keep new folders structured: space_map, read_skeleton, check_structure, create_folder, and move_folder. On a computer, instibrain check runs the same rules for any space, sealed ones included.
on /for-agents- kit name
A page or folder name that starts with insti but not with instibrain. Such names are the system's, so every write door refuses a new one inside a space.
on /for-agents- tool folder
tools/<name>/ in a space: a tool's page and the files it runs, synced to everyone the space is shared with. Only text files of a script's or a data file's type sync there, and a computer never writes one executable.
on /faq- approval
A manager's word for each file of a tool, by the SHA-256 of its bytes, in tools/<name>/approval.json. A computer runs or exports a file only at its approved hash, and in a sealed space only an approval a chain admin signed counts.
on /faq
What our server can read.
A space is open or sealed, and the keys are what a sealed space is made of.
- open space
A space our server reads. Its pages are stored as markdown, so an AI holding no key, on the web or a phone, can read them. Every person's Personal is one.
on /spaces- sealed space
A space our server cannot read. A page is encrypted on your computer before it leaves, path included, and only the computers of everyone it is shared with, which hold the space's key, open it. No web AI reads it. Every person's Sealed is one.
on /spaces- area
The pages under one key, or under none: always one whole space. An open space is one open area, which our server reads; a sealed space is one encrypted area, which it cannot.
on /spaces- key_id
The name of the key a page is encrypted under, or none for a page of an open space. A name for a key, never a key.
on /how-it-works- area key
A random 256-bit key, one per sealed space and epoch, wrapped once for each device admitted to it.
on /security- page key
The key one page is encrypted under, derived from the area key, the page's id and the epoch. No page has a secret of its own.
on /security- device key
The three keypairs a device makes for itself and never sends: X25519 with ML-KEM-768 to receive wraps, and Ed25519 to sign chain entries. They sit in the device's keys.json.
on /security- wrap
A key encrypted for one device's public key. The server stores wraps of area keys and cannot open any of them.
on /security- epoch
One generation of an area key. Removing a device or admitting one starts the next; an admitted device gets no earlier one, and the same sync sends every live page up again under the new key.
on /security- device approval
A person's yes to a new computer's fingerprint before it gets a sealed space's key. A teammate's first computer is approved on a manager's computer, each later one on a computer of theirs already in. A no is kept, and that device gets nothing.
on /security- recovery bundle
One file holding the whole keystore, device keys and every area key, sealed under a passphrase with Argon2id. You keep it off the machine it came from, and a key taken since makes it stale.
on /faq- membership chain
The append-only, signed log of which devices hold a sealed space's area key. A manager's device signs each entry, which carries the key wrapped for that device, and the sync client verifies the chain from its first entry.
on /security- the Blind Vault
The name of the encryption design behind sealed spaces. It names the design and nothing else, never a place a page is put.
on /security
Between a page and a file.
What the sync client does on your computer, and what it leaves behind.
- sync client
The part of instibrain that runs on your computer. It adopts, materializes, syncs and captures conflicts, and it holds the keys. Its command is instibrain, and each space it syncs is a folder under ~/instibrain/spaces/.
on /device- device
Any place you are: one of your computers, or one of your AIs. Each is you, never above your role, and the cockpit's Devices page lists them. In the encryption, a device is one folder a computer links, with keys of its own: it signs every request, and the brain holds only the public key.
on /computers- adopt
What the sync client does with a markdown file that has no id yet: it asks the brain for a new page id, writes the short header into the file, and pushes it.
on /device- materialize
Turning pulled pages into local files. The sync client materializes every page of the spaces it syncs as plain markdown.
on /device- cursor
Where a pull left off: seq, the space's own number, which each page takes when its write commits. A pull asks for every page numbered after its cursor, in commit order.
on /how-it-works- tombstone
What a deleted page leaves behind. The row stays and its content goes, so the next pull tells every computer the page was deleted.
on /how-it-works- conflict file
When a push returns 409, the sync client writes the server's version beside yours as a .conflict.md file and overwrites nothing. You merge the two, then run instibrain resolve.
on /device
How the server decides a sync write.
The server's only judgement on a sync write, and the vocabulary it uses.
- version vector
One counter per writer of a page: each synced folder that wrote it, and the brain, which counts every write through its own doors as one writer. Comparing two vectors tells the server whether a write has seen everything the stored copy has.
on /how-it-works- bump
Adding one to your own device's counter in a version vector, which records one local edit.
on /how-it-works- join
The least upper bound of two version vectors, counter by counter. The vector a merged page carries.
on /how-it-works- dominates
Vector a dominates b when every counter in a is at least b's and one is strictly greater. The one rule the server applies to a sync write.
on /how-it-works- 409
The answer to a sync write whose version vector does not dominate the stored one. It carries the server's vector, so your device can merge. The server never merges a page itself.
on /how-it-works
Your own AI, and the team's agents.
How your AI connects and what it reaches, and what an agent is.
- your AI
An AI that acts as you, wherever it runs: Claude Code, Codex, Claude on the web or the phone, or a program of yours on the API. It reads its reach, never more than you. Several can read one brain at once. It is never ours, and sync never waits on it.
on /agent- agent
A member of the team that is not a person, such as a support bot or a writer. The account owns it, an owner or an admin makes it, and a space is shared with it as with a person, at its own role.
on /spaces- room
Where your AIs, your agents, and your people talk, beside the spaces: each window, each AI login, and each agent is a voice of its own, and you read every room you are in. A message lasts 30 days, unless someone keeps it as a page.
on /rooms- window
One named Claude Code window on a computer. Its messages read as you, in that window, and it hears its rooms with nobody typing into it.
on /rooms- connection
One login of one of your AIs, approved once in the browser, with a credential of its own. You see it on Devices and sign it out there, which ends that login.
on /agent- reach
The spaces and specialists one of your AIs reads, each to read, or to read and write, never above your role. A new AI reaches nothing until you give it a place, on Devices.
on /security- proposal
A change an AI may not make itself, left in a space: a title, a body, and the page it is about. It belongs to the space: every editor and manager of the space sees it in the cockpit, and whoever makes the change closes it.
on /for-agents- specialist
A persona and a method an AI works as, shared with people, groups, and agents of its own, beside the spaces: ~/instibrain/specialists/<name>/ on a computer, made and shared in the cockpit. What a space knows for it is knowledge/<name>/ in that space.
on /specialists- the system
What defines instibrain, the same for everyone: the identity, the map, the staff in staff/, and the tools in tools/, each tool's how-to in its own folder. It is no space and is read-only; on a computer it is ~/instibrain/system/.
on /for-agents- MCP
The Model Context Protocol. The brain speaks it over Streamable HTTP, so an MCP client reads the open spaces of a brain with no SDK or plugin. Claude Code, Codex, and Claude have run on ours.
on /agent- brain.read, brain.write, brain.manage
The OAuth scopes a connected AI can hold. The approval page sets reading, and ticks writing and managing where the AI asked for them; the spaces it reaches are set on Devices. Managing acts as the AI's person, never above them: sharing, groups, invites, roles, removing a person, a new space, and the person's own computers, each change to people, access, or computers made only after the person's yes. A fourth, brain.sync, is the sync client's; no AI that signs in through the browser holds it.
on /tools
Put these words to work on your own company's pages.
Connect Claude Code, or ask for an account for your team.