Reference
Formatting (RetMD)
RetMD is the Markdown subset your cells are stored in. You normally never type it — the cell editor writes it for you — but because it's plain Markdown under the hood, your notes stay portable and future-proof.
Why Markdown at rest?
- Portability — your notes are readable text, not a proprietary format. They'll outlive any app, including ours; Export as Markdown writes them out verbatim.
- Safety — RetMD is rendered through a strict parser that builds content directly, so a captured cell can never inject markup or scripts into the app.
- Simplicity — a deliberate subset: enough structure for real notes, nothing exotic enough to break.
Block syntax
| Element | Syntax |
|---|---|
| Heading 1–3 | # Title, ## Section, ### Subsection |
| Bullet list | - item — nest with a 2-space indent |
| Numbered list | 1. item — nestable the same way |
| Checklist | - [ ] open task / - [x] done task |
| Quote | > quoted line |
| Code block | Three backticks on the lines before and after — an optional language tag (```js) labels the block |
| Table | GFM pipe rows: | a | b | with a | --- | --- | separator; :---, :---:, ---: set column alignment |
| Callout | :::note … ::: — also tip, important, warning, caution |
| Toggle | :::toggle Summary text … ::: — renders as a collapsible section |
| Divider | --- |
| Paragraph | Any other line |
Inline syntax
| Element | Syntax |
|---|---|
| Bold | **bold** |
| Italic | *italic* |
~~struck~~ | |
| Highlight | ==highlighted== |
Inline code | `code` |
| Underline | <u>underlined</u> |
| Link | [label](https://example.com) |
Links only render for http:// and https:// URLs — anything else stays inert text, by design.
One format, everywhere
Since v0.10.0, RetMD is the canonical storage format for every text cell — plain text is simply RetMD with no markup, so nothing was converted or rewritten. The same format is what the AI reads when indexing your notes, what the editor round-trips, and what exports produce. Cards render a read-only preview of it; open the editor to change it.
What RetMD intentionally leaves out
Footnotes, embedded HTML, and inline images are not part of the subset. Images in ReticulOS are first-class cells of their own rather than fragments inside notes — see Capturing Content.