Written links
Type [[ and a note's title, and you've linked them. Written links are yours: they're never scored, and rebuilding the map never removes one. They're drawn on the free map too.
Note connections
See relationships you might otherwise miss.
Cohestry shows three kinds of connection between your notes, and keeps them apart: the links you write, the connections it can prove from your notes, and suggestions from Apple Intelligence that you can confirm or dismiss.
Three layers, one map
Each line says where it came from.
Found in your notes
Deterministic connections, worked out on your device from what two notes contain. The same notes always produce the same map, and each line can tell you exactly why it exists.
Local agent
With local reflection on, Apple's on-device model looks for ideas the map cannot prove. Every suggestion quotes the notes it cites, and you confirm, correct or dismiss it.
Found in your notes
How a connection earns its line.
The engine reads names, references, distinctive vocabulary and tags, then applies two rules in order. Here are three real results from the example notes.
- A structural fact stands on its own. Two notes that cite the same page, attach the same file, link to the same note, or share a name little else in your notes uses are connected, whatever else they say.
- Everything else is scored. Shared names, distinctive vocabulary, tags and references are each measured against your own notes, so ordinary words count for nothing, and only a pair that clears the threshold gets a line. No note keeps more than six of these, and it keeps its strongest.
- It errs towards silence. A missing line is only absent; a wrong one would assert something your notes don't support. So the threshold sits above the strongest pair that shouldn't connect.
A shared rare name
Pairing with an AI on the essay ⟷ Tools shape the thought
“Both mention nietzsche”
- Shared names
- nietzsche
- Shared tags
- tools, writing
- Shared vocabulary
- writing
- Wording similarity
- 4%
These notes share a name that little else in your vault uses.
A shared reference
Resilience is redundancy ⟷ Small systems grow into complex ones
“Both link to balcony ecosystem, year two”
- Shared reference
- Both link to balcony ecosystem, year two
- Shared names
- balcony
- Shared tags
- systems
These notes point at the same thing, which connects them whatever else they say.
A weighted score
Balcony ecosystem, year two ⟷ My grandmother's tomato garden
“Both about seeds”
- Shared tags
- garden, seeds
- Shared vocabulary
- seeds
- Wording similarity
- 4%
No single signal connects these notes. Together they were strong enough to pass the threshold.
These examples come from a port of Cohestry's connection engine run over the example notes, on a configuration without the on-device embedding model. On your Mac or iPhone, a meaning-similarity signal can add further connections.
Local agent
When ideas rhyme without sharing words.
Some of the best connections can't be proved by overlap. With local reflection on, Cohestry hands a specific pair of notes to Apple's on-device model and asks whether they relate. A suggestion only survives if it quotes each note it cites, word for word.
Suggestions are drawn in gold and never move the map. Confirm one, write your own correction, or dismiss it; your original notes are never rewritten. Nothing is sent off your device.
Local agent · suggestion
Your novel keeps stalling for the same reason
Every draft of the novel tried to build the whole book at once, and every one stalled around chapter four. The systems note, written six years later, names the fix without mentioning the novel: start with the smallest version that works. The tending note describes the habit that would carry it. Read together, they suggest restarting from one small scene and returning to it for ten minutes a day.
The unfinished novel folder“every draft tried to build the whole book at once”
Small systems grow into complex ones“Start with the smallest version that actually works.”
Tending, not organizing“What survives is whatever I keep returning to for ten minutes at a time”
An example written for this collection in the shape the app uses.
Free and Pro
Your Brain is free. Its connections are the unlock.
Everyone gets the whole map of their notes, and one connection a day. Pro draws every connection, with its reasons.
22 notes · 15 written links · 27 connections available Reveal
22 notes · 15 written links · 19 connectionsPro
Today's insight · free
One connection a day, on Home.
The free app picks one pair the graph relates but you haven't linked, and says what they share. It changes overnight, and a tap links them.
Today's insight
“Tending, not organizing” and “The unfinished novel folder” may belong together
They share #projects, but neither links to the other.
Tending, not organizing The unfinished novel folder
Link them
A different reading of your notes each day.
Questions
About connections
Does Cohestry write links into my notes?
No. Connections found by the engine are drawn on the map and explained, but your text is untouched. Today's insight offers a “Link them” button; the link is only written when you press it.
Are all connections AI-generated?
No. Most are deterministic, worked out from what your notes contain with no language model at all. Suggestions from Apple Intelligence are a separate, optional layer, drawn in gold and always dismissible.
Why doesn't a note have any connections?
Because nothing in it clears the bar. The engine would rather draw nothing than a line your notes can't support. Link it yourself, or let it rest; it may connect to something you write later.
Do my notes leave my device to be connected?
No. The deterministic engine and local reflection both run on your device. Notes sync between your own devices through your iCloud account.
Is the example Brain on this site locked like the free app?
No. The example Brain is fully unlocked so you can see every connection. Pricing explains what's free in your own Brain.
Your thinking, made explorable.
Free on iPhone and Mac, with unlimited notes. Explore the example Brain first, no sign-up.
Explore the example Brain →