provenance
Where did this come from?
Each claim cites a source by id. Sources carry who wrote them, how often they're used and when they changed.
sources · usage_window
Open Knowledge Format · v0.2 · by Google Cloud
Knowledge your agents can account for
OKF is an open specification from Google Cloud for knowledge that agents write and people rely on. It's a folder of markdown files, and each file says where its claims came from, who checked them and when they expire. Knowtarium is built on it.
The bundle
A folder of markdown. Nothing else.
An OKF bundle is a directory of markdown files with YAML frontmatter. There's no database, no schema registry and no required tool: if you can open a text file, you can read it, and if you can copy a folder or clone a repo, you can share it.
Each file is one concept: a metric, a policy, a customer interview, a runbook. The only required field is type. Folders group concepts however suits the team, and two filenames are reserved: index.md lists what a folder holds, and log.md records what changed.
bundle
~/kb/index.md # what's in this folder (optional)log.md # what changed, newest first (optional)company/mission.mdglossary.mdmetrics/revenue.md # one concept per filechurn.mdcomputations/quarterly-revenue.md # an attested computationcustomers/segments.mdinterviews/northwind-traders.md
Inside a document
Four questions, answered in the frontmatter.
When agents write most of a knowledge base, a reader needs more than the text. OKF v0.2 adds a few optional field families that make every document answer the same questions. They're all optional: a document with just a type is still valid, and a missing family simply means the answer is unknown.
Claims in the body cite sources with footnotes keyed by id, like [^billing-export], so the link survives when an agent reorders the list.
metrics/revenue.md
---type: Metrictitle: Quarterly revenuetags: [finance, revenue]status: stablegenerated: { by: claude-code/2.1, at: 2026-09-26T07:42:00Z }verified:- { by: human:maya, at: 2026-09-26T10:05:00Z }stale_after: 2026-12-31T00:00:00Zsources:- id: billing-exportresource: exports/billing/2026-09.csvauthor: process:billing-syncowner: human:maya # your own keys are kept as written---Q3 revenue was €112,400, up 12% on Q2.[^billing-export]
trust
Who checked it?
Who wrote the document, and every person or process that confirmed it since, with the time.
generated · verified
lifecycle
Is it still current?
A draft, stable or deprecated status, and the moment the document stops being safe to quote.
status · stale_after
attestation
Was this number computed the approved way?
A computation lives in its own document. Agents fill in the parameters; a deterministic check confirms the approved query is what ran.
runtime · parameters · executor · attester
Trust tiers
Derived, never declared.
No document gets to call itself trustworthy. A reader works out the tier from who is listed under verified, and staleness from stale_after. With review turned on, Knowtarium colours every note by these rules and nothing else.
unverifiedNo
verified entries at all.machine-confirmedVerified only by agents or processes, such as process:ci.
human-reviewedVerified by at least one person, such as human:maya.
staleThe current time is past
stale_after, whatever the tier.Who did it
Every by field names an actor in one of three forms. The human: prefix is what makes a verification count as a person's review.
- claude-code/2.1
- An agent or tool, with its version
- human:maya
- A person
- process:finance-nightly
- An automated process
Knowtarium and OKF
What the app reads and writes.
Knowtarium stores every note as OKF, encrypted on your device. It follows the spec closely, so what you import comes back out as a bundle every other OKF tool can use.
It imports any bundle
Import an OKF bundle or an Obsidian vault into a workspace. Missing fields, unknown types, unknown keys and broken links never make a note unreadable.
Exports are plain OKF
Export every workspace as an OKF bundle in one zip, decrypted in your browser, ready for any other OKF tool.
Your own keys stay put
Custom frontmatter keys, comments and formatting are kept exactly as written, as the spec asks.
A person's name has to be signed
A human: entry only counts when that person's own signed change confirms it, so an agent can't pass its work off as yours.
Review is optional, and writes one entry
Turn on review for a workspace or folder, and approving a change adds you to verified with the time. That's the only field review writes.
History stays out of your notes
Versions, comments and signatures are stored next to each note, encrypted, so the notes themselves stay clean OKF.
Coming from Obsidian
Your vault is most of the way there.
An Obsidian vault is already a folder of markdown with frontmatter. Import it into a workspace, or convert a copy offline with : the OKF fields are added, wikilinks become markdown links and an index is written, without touching your writing.
OKF is an open format published by Google Cloud in the open-knowledge-format repository on GitHub. Knowtarium is an independent app, not affiliated with or endorsed by Google.