Eidos or Notion: where should your specs live?
Notion is the all-in-one workspace where many product teams keep their PRDs, specs, and wikis. Eidos keeps each part of the product in one markdown file beside the code, checked against a framework you choose. They do different jobs, and many teams will keep both.
The short answer
Pick Notion if design, sales, and leadership all need to write and comment on the spec in a browser, next to roadmaps, meeting notes, and tasks. Pick Eidos if the spec should be a file in your repository, reviewed with the code, checked against your team’s framework, and read by your coding agent like any other file.
At a glance
Eidos and Notion, side by side
| Question | Eidos | Notion |
|---|---|---|
| Where a spec lives | A markdown file in your repository | A page in Notion’s cloud |
| Checked against a declared shape | Yes, on your machine and in CI | No: a template is a starting point |
| Versioned and reviewed with the code | Yes: git history and pull requests | Page history, 7 to 90 days by plan |
| Real-time co-editing in a browser | Live in the desktop app; no browser view yet | Yes, with guests |
| Views over every spec | Tables and filters over the files | Databases with relations, rollups, and timelines |
| AI | Your own agent, which asks while you write | Notion agents that draft and edit; full AI on Business and up |
| Leaving | Nothing to export: plain markdown | Markdown and CSV export; relations and views are lost |
| Price | Free locally; online, $4.99 a month per editor past three | Free plan, then per member |
Where Notion is the better choice
- Everyone takes part with nothing to install: a shared link, real-time co-editing, inline comments, and guests. Eidos online edits live too, but only in the desktop app. There’s no browser view of an Eidos project yet.
- Databases turn a pile of PRDs into a portfolio: every spec by status and owner, with relations, rollups, and timeline views.
- A new PRD starts full, from a database template or the public gallery, with nothing to set up first.
- AI where the writing happens: agents draft, fill in properties, pull context from Slack, Drive, GitHub, and Jira, and suggest edits a person approves line by line.
- Coding agents can reach it too, through Notion’s MCP server and its markdown API.
- Most product people already know it, and the company may already pay for it.
Where Eidos wins
- More than a template: every spec is checked against the sections and fields your framework declares, on your machine and in every pull request. The check stays lenient until you turn strictness on.
- The spec lives beside the code: plain files in your repository, with git history, reviewed in the same pull request as the change.
- Nothing to export, ever: plain markdown written to EIDOS.md, an open Apache-2.0 standard that every editor and agent reads.
- A person writes it. Your own agent reads the files, asks where you were vague, and pushes on scope. Eidos never writes a spec for you.
- Built for defining a product: frames for the audience, the market, and the architecture, and permanent ids that tasks, canvases, and comments point at.
- Free and local with no account, and free online for viewers, commenters, agents, and the owner plus two editors. AI runs on the agent you already pay for, with no credits to buy.
Can you switch?
Bring your specs over, or keep both
Export the specs from Notion as Markdown, and install the software framework in your repository. Make each spec with New blueprint in the app or eidos new, which gives it an id and its fields, then paste the exported page under the template’s headings. The check lists what each one still lacks. Many teams keep Notion for notes and planning, with links to the spec in the repository.
- Plain markdown in, plain markdown out
- The check names what each spec still lacks
- No Notion importer yet: specs come over by export and paste
$ eidos install @BuildableWorks/software Blueprints --group payments --yes
✓ installed @BuildableWorks/software → Blueprints
collections: frames, specs; groups under specs: payments
$ eidos new specs "Refunds" --group payments
✓ specs/payments/refunds.md (specs, spec.full, id B-QQJ7)
$ eidos ci --write github
✓ created .github/workflows/eidos-check.yml: eidos check on every pull requestWhat this page says of Notion was checked against its own pages and docs in October 2026. Products change; if something here is out of date, tell us with Send Feedback, under Help in the app.
Compare
Other comparisons
- Team wikivs ConfluencePick Confluence when the whole company reads the spec beside Jira. Pick Eidos when the spec should be checked and reviewed with the code.
- Spec-driven developmentvs GitHub Spec KitPick Spec Kit to drive an agent from spec to code, change by change. Pick Eidos to keep a checked definition of the product as it stands.
Put one spec beside the code this week.
Download Eidos MD, open your repository, and write the next spec as a blueprint. Notion can keep everything else.
Free for macOS, Windows, and Linux. Your files stay plain text in a folder you own.