Claude, ChatGPT, Codex and Cursor file the plan, the decision or the answer into your notes and hand back a link. It is still there when the chat is gone.
1,000 pages free. No card. You write in it too: instant, offline.
Auth rewrite plan
Filed by Claude Code · just now
Decided
Rotate refresh tokens per session, not per request
Keep 15-minute access tokens
Next
Fix the clock-skew test
Ship behind a flag on Thursday
The vault itself, on the free plan, in your browser. What you write stays on this device, and comes with you if you make an account.
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Start here
This is the real editor
Everything here works the way it does in a signed-in vault, and everything you write stays in this browser. Type anywhere. Break things. Nothing here needs an account.
Try these
One command files it as a page in your vault and prints a public address in the same breath. Revise the file, run it again, and that address is still right, because it is the same page. Other notes tools take what an agent writes and then stop: the sharing is left to you, in their interface, one page at a time.
Send this prompt to Claude Code
Fetch https://sumibako.com/skill.md in full and follow it. If your web tool summarizes pages, use curl.It reads the skill and uses it for this session. Nothing is installed.
The same command runs in CI or a script, with a token in the environment.
One shortcut opens a capture box over whatever you are doing in the vault. Type or speak, save it, and you are back where you were with it kept - even with no signal.
Quick capture
First line becomes the title. Saves without leaving this page.
Search runs over every word you wrote, not just the titles, and lights up the words it found. Type @ to link two pages and each shows what points back at it. Today's page is one key away.
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The renewal runs to March unless notice is given by the end of January.
Q3 planning
Budget the renewal under tooling rather than under the platform line.
Linked from
CtrlJtoday's pagePublish and the page is a real URL with its own preview card, styled the way you wrote it. Unpublish and it is private again the same second.
Rollout plan
Three weeks, two regions, one switch to roll it back. Nothing ships on a Friday.
Rollout plan
Three weeks, two regions, one switch to roll it back.
This note is live on web.
Let search engines find this page
Off by default. Your link keeps working either way.
Drop in a Notion export or an Obsidian vault and your pages arrive with their nesting intact. You choose which ones come across before a single one is written.
Export as Markdown, drop the zip in - nesting and all
Zip the vault folder; your directory structure becomes the tree
Two things do not come across yet: Notion databases, which export as CSV, and images, which stay behind rather than arriving as broken links. The import stops at your plan's note limit.
Drop a Notion or Obsidian export here
my-notion-export.zip
What lands in your vault
It is a good product, and a lot of product. Here is the split, so you can stop reading early if this is not for you.
The free tier is not a trial. It has no expiry, no card on file and no feature held hostage - most people never leave it, and that is fine.
$0forever
Enough to actually live in, not a countdown to a paywall.
$4per month
Or $39 a year, which works out to $3.25 a month.
Yes, on every plan including free. Any document exports to Markdown from its own menu - the whole page, formatting intact. Data portability is a precondition for trusting a notes app, so it is not something we hold behind the paywall.
You can read and write. Pages are cached locally, edits you make with no connection are queued, and everything syncs the moment you are back on. Creating, editing and trashing all work in the air. Worth knowing: that holds for an app that is already open, so open it before you lose signal - starting it cold with no connection is not supported yet.
Yes. Export from Notion as Markdown, or zip your Obsidian vault, and drop the file in - your pages arrive with their nesting intact, and zips inside zips are unpacked for you. You pick which pages come across before anything is written. Two things do not come with them yet: Notion databases, which export as CSV, and images, which stay behind rather than arriving as broken links.
No. It is a door, not a requirement. Sumibako is a notes app first; the agent feature only exists once you run a command or connect a client, and nothing in your vault changes until an agent writes into it. Most people never will, and that is fine.
It can, and that half is good: Notion takes Markdown directly and its connection is a browser sign-in. What it cannot do is publish. No Notion endpoint and none of its agent tools turns on Share to web - the public address is a read-only field - so the agent writes the page and you still open Notion, find it, and click through Share and Publish before there is anything to send. That is the step this removes: the link is printed by the same command that files the page, and it stays pointed at the same page when the agent revises it. Checked against Notion's developer changelog on 2026-09-10.
Write pages, read them back as Markdown, and add to or correct what is there. It cannot delete anything - there is no delete in the API - it cannot make a page findable by a search engine, and it cannot reach any account but the one that made its token or approved its connection. The last 20 versions it overwrites are kept for 14 days, and you can revoke it in Settings at any time.
No, and it starts writing as you speak rather than making you wait for a transcript. It uses the speech engine already in your browser, which Chrome, Edge and Safari all have. Firefox has no such engine, so dictation is not available there - the button is present but disabled and tells you why. Worth knowing: Chrome's engine transcribes by sending audio to Google, so dictation is not an offline or on-device feature.
Search covers titles and body text and runs offline, and pages link to each other: type @ to point one note at another, and the note you pointed at shows what links to it. Old writing resurfaces because you referenced it, not because you filed it correctly on the way in.
They stay. Downgrading returns you to the free plan's limits for creating new things - nothing you already wrote is deleted, locked or hidden, and you can still read, edit and export all of it.
In Convex, the backend this runs on, tied to your account and nobody else's. Documents are private until you explicitly publish one, and unpublishing takes it off the web again immediately.
It installs as one. Sumibako is a progressive web app, so adding it to your phone's home screen gives you a real app icon and its own window - without an app store in the way.
That is the entire onboarding. Whatever you wrote in the editor above comes with you.
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