Markset
Markdown, with layout
Documents your agents write, and people want to read
Agents draft most documents now, and they already write Markdown. Markset adds cards, grids, tabs, metrics, charts and callouts, so what they write reads like a designed page, and is still a Markdown file that reads anywhere Markset is not supported.
v0 0.4.2 CommonMark superset
Markdown source → rendered layout
:::metrics
| Metric | Value | Δ |
|---------|-------|-------|
| Revenue | $4.2M | +12% |
| Churn | 2.1% | -0.4% |
:::
The example above is the whole idea: a Markdown table in a fence that names what it is. Rendered, it becomes metric tiles. Anywhere else, it is the same table. The construct adds meaning without taking the content hostage.
With agents
Why agents should write Markset
Cheap to teach
Agents already write Markdown. Markset adds eight constructs and one way to attach a class, so the whole guide fits in a few pages of an agent's context.
Checked before you read it
The vocabulary is closed and every mistake has a code, so an agent checks its own document and fixes it before handing it over.
Consistent across documents
The agent says what each thing is and the theme decides how it looks, so fifty documents from fifty prompts read as one organization's.
Reviewable
The source is plain text, so a diff shows what changed in the content rather than in hundreds of lines of markup.
Safe to render
Nothing runs and no raw HTML passes through, so a document an agent wrote can be rendered without reading it first.
Readable everywhere
Every construct degrades to plain Markdown. Paste the document into a pull request, an email or a chat, and it still reads.
See the same document written twice, as plain Markdown and as Markset, by an agent that had only the guide.
Tools
Where you can use it
In VS Code
Review what an agent wrote in the Markdown preview you already use. Every construct is offered after :::, and a mistake is underlined as you type.
In your own app
A TipTap editor for people who should never see the syntax. Saving writes Markset back and changes only the lines they edited.
In your browser
The playground runs the parser and both renderers on your machine: the page, its HTML, the plain-Markdown fallback and the diagnostics.
From the command line
Check a document, which is how an agent checks its own, render it to HTML, or lower it to plain CommonMark. It also carries the guide agents write from.
In a remark pipeline
Add Markset to the Astro, Next or Eleventy build you already run, as one remark plugin, without replacing anything around it.
On GitHub Pages
Publish a folder of Markset documents as a site with one workflow file. This site is built that way.
Principles
Three rules it does not bend
Semantic, never presentational
Authors name what a thing is, not how it looks. The theme decides whether a card has a border.
Every construct degrades
Each one wraps an ordinary Markdown block and has a defined fallback. Paste a file into a GitHub comment and it still reads.
Closed vocabulary
Eight constructs, and an unknown one is a reported error rather than silent passthrough, so a document can be checked before it ships.
Why Markset exists, and how it compares with Pandoc, Quarto, MyST, Markdoc and MDX.
Next
Read further
The reference
A page per construct, with live examples taken from the test suite.
The specification
Short, and the source of truth: when the code and the spec disagree, the spec wins.
The examples
Complete documents, each with a theme of its own, showing how far appearance moves while the source stays plain.