What a good page has
- A clear title and readable text. Not a raw dump of the source, but a tidy write-up a person would be happy to read.
- A place in the structure. Pages live in folders, organised the way the brain’s template lays out, so related things sit together.
- Links to related pages. A meeting page links to the people who attended; a project links to its decisions. Following links is often faster than searching.
- Citations. At the bottom of a page is a note of where its information came from and when. This is what lets you, and your agents, trust what a page says: you can always trace it back. When the source lives somewhere, the citation carries two links: the copy that was read, kept unchanged in Sources, and the live document.
The right size for a page
A page is one topic. The target is 300 to 1,500 words: long enough to say something, short enough that a search hit lands on the answer rather than somewhere inside a wall of text. A long document does not become one long page; it becomes an overview of under 500 words that links to one page per topic, each citing the place in the document it came from. The document itself stays in the inbox archive, one click away. A page that grows past 2,000 words shows on the brain’s Health page as oversized. That is a count for you, not work Cortex does: the rule is for new writing, and nothing rewrites an existing page because of its size. Your agent follows the same rule. It files a long document as an overview and topic pages, and when it updates a page it changes only the part the new content touches. A page that grows by appends, a person’s page with a dated line from every meeting and mail, a project hub with a session log, is folded for you. Every hour Cortex looks at each page over the line and moves the dated lines older than six months out of its Timeline and Session log sections to a history page beside it, at the same address with-history on the end. The lines move exactly as written, indented detail included; nothing is summarised and nothing is deleted. The page ends the section with Older entries: [[...-history]] and the history page opens with a link back, so either is one click from the other. The newest twenty dated lines stay whatever their age, so a quiet page is never emptied. If the page is still over the line once the old lines have gone, the oldest of the rest follow, one at a time, until it is under the line or only the twenty are left: a busy page is over the line long before anything on it is six months old. Lines without a date, paragraphs and the current-state sections are not touched. A history page is never folded itself and does not count as oversized.
What is left for you is a page that is really several topics. Move each topic to its own page and leave an overview under 500 words at the original address, so links keep working. Until 7 October 2026 Cortex queued oversized pages for a model rewrite instead; that was withdrawn because a model rewriting a page that grew by appends loses detail, and those are exactly the pages that grow.
Two pages are never counted: your brain’s task page and its archive. A task list is one list however long it gets, and Cortex keeps it short a different way, by moving ticked tasks to the archive a week after you tick them.
The front page
Every brain with content gets a front page,_index.md at the root, kept by Cortex’s hourly maintenance: the brain’s name and description, then a line per folder with how many pages it holds and a link to the folder’s own index page. Cortex keeps it current only until you edit it; after that it is yours and Cortex leaves it alone. A brain organised into clients has its roster as the front page instead.
Brains grow with use
A template gives a brain its intended structure. The structure it actually has is whatever holds pages, and the two are allowed to differ. A page saved to a folder that does not exist yet creates that folder. Your agent sees both: the folders the template describes and every folder that holds pages, with how many and what kind, whether or not it is described. A folder that is in use is a proper place to file, so the agent prefers a folder you already have over inventing one; when nothing fits it creates one, names it plainly, and tells you. Once a new folder has settled, describe it in the brain’s Settings: a line on what belongs there and how it links to the rest. That description is what every later filing, by an agent or by Cortex, reads. The brain’s instructions page should mention it too, or the agent’s first-write check will point out a folder the instructions do not cover.Finding a page
The Workspace opens with every folder closed, so even a large brain starts as a short list. Open the folders you use and Cortex remembers them, in that browser, for that brain. The two buttons beside Name and Recent open or close them all at once. However you reach a page, from the tree, a link in another page, a backlink or a link someone sent you, the folders above it open and its row comes into view. Name sorts folders and pages A to Z; inside a folder, pages whose names start with a date come first, newest first. Recent lists every page in one column, last changed first, with its folder and how long ago it changed. Click the folder to go back to the tree, opened there. The filter box works in both. In a brain divided into clients or accounts, Recent covers the ones you have opened and says so.On your phone
The Workspace works on a phone. Open a brain and the page fills the screen; Pages at the top slides the folder tree in, Info slides in the backlinks and page details, and a tap outside puts them away. Reading, editing, history and delete are the same as on a desk. The editor is the same editor, so a page saved from your phone is exactly the text you typed, with its version kept like any other. Two things are quick enough to do while walking. The round + button at the bottom left of every brain page offers them:- Task: one line onto your task page, with a due date if you know it and the section it belongs in.
- Topic: something to raise with a person. Type a few letters of their name, pick them, type the topic. It lands under To Discuss in their Topics section, dated today, as a talking point for your next catch-up. If you were reading a page at the time, the topic links to it unless you untick the box.
Nothing is lost to an edit
Every page keeps its full version history. When a page changes, whether you edit it or an agent files an update into it, the previous version is kept. You can look back at what a page said before, and see how your knowledge evolved. Editing is safe: you can never quietly overwrite something and lose it.Why structure makes recall better
A well-structured brain is easier to recall from, for you and for your agents. Citations mean answers come with sources. Links mean related knowledge is one hop away. Sensible folders mean things are where you would look. The skills that do the filing exist precisely to keep this structure consistent, so recall stays good as a brain grows.Try it
- Open a filed page and read it top to bottom, ending on its citation.
- Follow one of its links to a related page.
- Open the page’s version history and look at an earlier version.