Comparison · Knowledge base

NOAN vs Obsidian

Obsidian is a second brain for a person: local markdown files, linked notes, private by design, free, and genuinely excellent at thinking. NOAN is a brain for a company: a smaller set of verified, versioned facts served to agents, apps, teammates, and your website over an API. Many builders today point AI at a vault of markdown files and call it grounding. It works until it matters: a file cannot tell an agent who approved it, when it changed, or whether it is still true. A fact can. Keep Obsidian for your thinking. Give the company NOAN for its truth.

Side by side

Competitor claims last verified 26 August 2026
DimensionNOANObsidian
What it isThe company brain and API: verified facts, tasks, contacts, notes, and assets behind one REST endpointA local-first markdown knowledge base: linked notes, graph view, plugins, your files on your disk
Source of truthApproved, versioned facts with an owner; one source of truth for the whole companyWhatever the file says; drafts, ideas, and decisions look identical to a reader
VerificationFacts enter through a verify gate: a human approves before anything reads it as trueNone; that is the point of a personal notes tool
APIPlain REST plus MCP, bearer keys, unlimited API keys on every planNo official API; files are readable by anything, which is both the charm and the limit
AgentsBuilt for agents: facts to ground on, a task board to control them, any modelAgents can read vault files as context; no approval, versioning, or task control around what they read
AuditabilityEvery fact versioned with full history and Time Travel; every agent action lands on the task boardFile history only if you add git or Sync version history yourself
Pricing modelWhole-workspace plans from $99/month; unlimited keys, no per-agent or per-task meteringFree for personal use; Sync $4 to $5 per user per month, commercial license $50 per user per year
Lock-inFacts are plain text behind a REST API; one GET exports everythingNone at all: plain markdown files you own outright

When to choose Obsidian

  • Personal notes, research, and thinking, where linking ideas matters and nobody else needs to trust the contents
  • You want local-first privacy and files you own with zero lock-in
  • You are one person grounding your own AI on your own notes and you accept the drift

When to choose NOAN

  • More than one person, or any agent, needs to rely on the knowledge being true
  • Facts need owners, approval, versions, and an API rather than a folder path
  • Your website, apps, and agent fleet should update together when a fact changes

The deeper comparison

Why the vault-as-knowledge-base pattern breaks

Pointing an agent at a folder of markdown is the most natural first move in agentic building, and for a single person it genuinely works: you wrote the notes, you know which are current, and the blast radius of a stale one is your own afternoon. The pattern breaks along two axes at once. Add people, and the vault fills with notes of unknown status written by others. Add stakes, and the agent starts asserting file contents to customers, in code, or in money-touching workflows.

The missing ingredient is not search, it is metadata that files structurally cannot carry: who approved this claim, when did it change, what previous version did it replace, what reads it downstream. Front matter can gesture at this, but nothing enforces it, and an agent cannot tell disciplined front matter from decorative front matter.

NOAN's facts are that metadata, made first-class. A fact without an approver does not serve as true. A change creates a version rather than overwriting history. And because facts are served over an API rather than read off a disk, the same governed truth reaches an agent on your laptop, a cron job in the cloud, and your public website, which a local vault cannot do without becoming a sync problem.

What each one costs you

Obsidian is free for personal use, with Sync at $4 to $5 per user per month and a commercial license at $50 per user per year. As personal software it is one of the great bargains in tools.

NOAN starts at $99 a month per workspace with unlimited API keys. The comparison is not really price, it is job: nobody should pay for governance they do not need, and a personal vault does not need it. The moment the knowledge stops being personal, when a teammate, an agent, or a website has to rely on it being true, the cost of not having governance shows up as incidents instead of invoices.

Keep the vault, promote the truth

The workable pattern is the same one we recommend beside any writing tool: think in Obsidian, assert in NOAN. Your vault stays the place ideas link and compound, private and local. The subset of claims that harden into company truth, what you charge, what you promise, how you operate, gets promoted into verified facts, which is usually a few dozen items rather than the thousands of notes around them.

Mechanically the promotion is trivial: facts are plain text behind a REST API, so a markdown-native workflow fits naturally. Some builders keep a vault note per fact as the drafting surface and treat the POST as publication. The vault remains yours; the facts become the company's.

Common questions

Can I use my Obsidian vault as a knowledge base for AI agents?

You can, and for personal use it works: point the agent at the files. The failure mode arrives with stakes and with teams: files carry no approval, no versioning an agent can check, and no way to know a note is stale. Grounding a company agent on a vault means acting on whatever was last saved, by anyone, for any reason.

Is NOAN an Obsidian alternative?

Not for personal knowledge management; Obsidian is exceptional there and free. NOAN is the alternative for the company layer: the facts that must be true, verified and served over an API. Different altitude, honestly different tools.

What is the difference between markdown files and facts?

A markdown file is content; a fact is a governed claim. The fact carries an owner, an approver, a version history, and a list of everything reading it, and it is served over an API. The file is perfect for thinking; the fact is safe for acting.

What is the best Obsidian alternative for teams?

For shared personal-style notes, tools like Notion fill that gap. For the layer Obsidian was never meant to be, machine-readable company truth, the alternative is a fact layer: NOAN gives claims owners, approvals, versions, and an API, which files cannot enforce.

Can Claude Code read my Obsidian vault as context?

Yes, trivially: a vault is markdown on disk, and that is exactly why builders start there. It works until the stakes rise. The vault tells the agent what a file says; it cannot tell the agent whether the company still stands behind it. That second property is what NOAN adds.

Should I migrate my Obsidian vault into NOAN?

No, and we would advise against trying. Migrate claims, not notes: the few dozen truths your business asserts belong in NOAN as verified facts, and the thousands of notes that produced them belong exactly where they are, in your vault, linking and compounding.

Sources: obsidian.md/pricing · All comparisons

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