capture·organize·prioritize·act

The second brain that turns ideas into reality.

Capture any thought, link, video, or file. Cranium files it under the right vault, connects it to your priorities and goals, and helps you turn what you save into what you actually do.

capture·listening
how it works

Capture it. File it. Move on it.

Cranium is your filing cabinet, your priority board, and your second brain — in one place. You drop ideas in. The system organizes them, connects them to what you’re working on, and surfaces what they actually mean.

01
C
Capture
Anything, in one box
Thoughts, links, videos, files, screenshots — drop them in as they hit. Cranium reads, summarizes, and tags every capture the moment it lands.
02
V
Vaults
Your filing system
Set up folders for the parts of your life that matter — Trading, Health, Family, your business. Captures slot into the right vault automatically.
03
P
Priorities + Goals
Turn it into action
What you’re working on this week, what you’re aiming at this year. Cranium connects every capture to the priority or goal it serves.
04
K
Knowledge
Wisdom that compounds
As your captures stack up, Cranium reads across each vault and writes what you’ve come to know. The thinking gets sharper. The patterns surface themselves.
sources

Bring your feeds in. Get them back smarter.

Connect the channels you already read. Cranium pulls every new item the moment it drops, summarizes it, transcribes the video ones, and files it under the vault it actually belongs to. The longer you use it, the smarter your account gets.

//
RSS
Newsletters + blogs you actually read
Add any RSS or Atom feed — Substacks, blogs, news sites. New posts arrive as captures the moment they publish.
  • Full article body fetched + cleaned of footer spam
  • AI summary — the gist before you click in
  • Auto-filed into the right vault by topic
@
𝕏
Tweets + your bookmark vault
Drop any tweet URL into capture. Or connect your X account once and Cranium pulls every bookmark you've ever saved — and keeps syncing the new ones.
  • Author, body, media, and metrics on every capture
  • AI summary so a thread doesn’t need a re-read
  • Filtered by source — see only X when you want only X
YouTube
Channels you follow, transcribed
Subscribe a channel; every new upload becomes a capture. Or paste a single video URL. Cranium fetches the description and the full transcript automatically.
  • Full timestamped transcript pulled on capture
  • AI summary built from the transcript, not the title
  • Shorts auto-flagged so they don’t drown your feed
// the compound effect

Every summary and transcript makes your account smarter.

Searchable on day one. Once the transcript or summary is there, you can search the idea inside it — not just the title.
Cross-vault patterns. Cranium reads across captures and surfaces the threads you didn’t notice — three videos and an article all circling the same idea.
Daily + weekly letters get sharper. Every transcript, summary, and bookmark is fuel for the letters that find your wins, drift, and what’s taking shape in your vaults.
// direction of travel

Momentum is easier to feel when you can see it.

Every goal and priority has a trajectory. You tell Cranium how it’s going, on a slider from drifting to moving. Those signals stack into a line you can read at a glance — and a Sunday letter that tells you the truth.

Sample priority · 30-day trajectory
+7
30 days agotoday
01
One slider, two directions
Drifting on the left, steady in the middle, moving on the right. No ambiguity.
02
A note, if you want
Each entry can carry a line. That line trains your Sunday letter.
03
The line draws itself
Entries add up over 30 days into a cumulative chart you can actually read.
vaults · knowledge

Your filing system thinks for itself.

Vaults are folders for the parts of your life that matter. Drop captures in by hand or pipe in YouTube and RSS. Once a vault has a few captures, Cranium reads across them and writes what you’ve come to know — the patterns, the through-lines, the open questions.

// VAULTS
filing that organizes itself

Vaults are folders for what matters in your life. Trading. Health. Family. Premium.Chat. Set them up once. Every capture you make — by hand, from a YouTube channel, from an RSS feed — drops into the vault it belongs in.

Pin a YouTube channel or RSS feed directly to a vault and new episodes arrive pre-filed. Cranium scrapes the transcript, strips the SUBSCRIBE-and-LIKE boilerplate, and writes its own summary on the way in.

No more sprawling notes app you can’t find anything in. The captures live where they belong.

— cranium.os
// KNOWLEDGE
what you've come to know

Once a vault has more than a handful of captures, Cranium reads across them and writes a living summary — what the patterns are, what the through-lines are, where the open questions sit.

You don’t have to remember which video said what or which note made which point. The vault knows. The longer you use Cranium, the sharper that read gets.

Same captures you would’ve saved anyway — just compounding into wisdom instead of piling up as clutter.

— cranium.os
conversation

Cranium replies as someone who actually knows you.

Open any capture, priority, or goal and ask. Cranium pulls in what you’ve saved, what your vaults have come to know, and where you said you wanted to go. The reply comes back grounded in your actual context — not generic advice.

askyour context loadsdirect replyfeedback adapts it
// SAMPLE REPLY · WITH YOUR CONTEXT LOADED

Talk to Cranium

opening a capture · asking what it connects to
sample —
your conversations
look like this
youWhat does this Graham Stephan video about Tesla actually connect to in my Trading vault?
the capture you openedThe video’s title, transcript, and the summary Cranium wrote when you saved it.
what else is in that vaultThe other captures you’ve saved on this thread — past videos, articles, notes — so Cranium can see what you’ve been thinking about.
what the vault has come to knowThe living summary Cranium has built across this vault’s captures — your patterns, your through-lines, your open questions.
your priorities and goalsWhat you’re actively working on in Trading right now and what you said you were aiming at this year. Cranium isn’t answering blind — it’s answering as someone who knows what you care about.
// cranium · replies in your voice

“Three threads. Stephan’s thesis on Tesla parallels what you saved from Dumb Money two weeks ago — both treat the EV multiple as a battery story, not a software story. Your Trading vault has 14 captures on margin compression, and that’s the lens you keep returning to. The open question your vault has surfaced is whether margin compression is cyclical or structural — Stephan implies cyclical, your earlier reads on Munger imply structural. Worth sitting with that disagreement.”

Tell Cranium what you want different. Your feedback shapes the next reply — and the next Sunday letter.
— cranium.os