Brains
Brains are personal knowledge collections. When you add content to a Brain, your companion can reference it when answering questions, drafting content, or helping you think through problems.
Creating a Brain
Section titled “Creating a Brain”Open Brains from the sidebar and create a new one. Give it a name, then add content — the create flow walks you through both.
Your companion auto-generates a description for the Brain after you add content, so you don’t need to write one yourself.
An empty Brain shows you the two ways to fill it — upload a file, or link existing notes and pages — rather than sitting blank.
What you can add
Section titled “What you can add”Documents — Upload files directly into the Brain. Supported formats:
.pdf .epub .docx .doc .txt .md .csv .rtf .vtt .srt
Files up to 50 MB are read and indexed. Subtitle files (.vtt, .srt) are read as plain text, so a meeting transcript can go straight in. You can also paste text directly without uploading a file.
Notes — Link existing notes from your Notes app into the Brain.
Pages — Link pages you’ve written in the Pages app into the Brain.
Size tiers
Section titled “Size tiers”When creating a Brain, you can set a size tier that determines how much content it can hold:
| Tier | Use case |
|---|---|
| Focused | Tightly scoped topic — a single project, person, or concept |
| Standard | General-purpose knowledge collection (default) |
| Deep | Large or comprehensive knowledge base |
How your companion uses Brains
Section titled “How your companion uses Brains”When you’re in a conversation, your companion checks your Brains to see if any are relevant to what you’re discussing. If so, it pulls in that content as context — you don’t need to reference the Brain by name.
You can also mention a Brain explicitly:
“Based on my Marketing Brain, what should I prioritise this week?”
Archiving Brains
Section titled “Archiving Brains”You can archive a Brain you no longer need. Archived Brains don’t appear in the active list but aren’t deleted.