markdown

docbin renders GitHub-Flavored Markdown and adds callouts, structural and interactive directives, an embed allowlist, tabs, and a frontmatter block. This page documents every element the renderer understands. The same reference is available as raw text at /markdown?format=raw or from the CLI with docbin markdown.

base markdown

Tables, strikethrough, and task lists work as in GitHub. Math renders through KaTeX with $...$ and $$...$$; diagrams render through Mermaid in a fenced mermaid block. Fenced code is highlighted, including the custom log, westmyth, and accesslog grammars.

callouts

A callout is a fenced container opened and closed with three colons. The word after the colons is the type.

:::note
Body content here.
:::

Ten types: note, info, tip, warning, caution, important, success, danger, question, quote. GitHub alerts (> [!NOTE]) render as callouts too.

structural directives

Six containers shape content: details, steps, compare, cards, card, and figure. To nest one container in another, give the outer one four colons.

::::cards
:::card{title="First"}
Body of the first card.
:::
::::

interactive

A badge is inline: :badge[label]{variant=note}, with the same ten variants as the callout types. An embed renders a sandboxed iframe for an allowlisted host (YouTube, Vimeo, CodePen, CodeSandbox, StackBlitz); any other URL becomes a plain link. tabs groups sections behind a tab strip, one per @tab line.

frontmatter

An optional YAML block at the very top, fenced by ---, sets document options.

---
title: My Document
toc: true
toc_depth: 3
toc_side: right
tags:
  - reference
---

Twelve keys are recognized: title, description, theme, toc, toc_depth, toc_title, toc_side, author, date, tags, reading_time, hide_title.

full reference

Read the whole spec as raw markdown for piping or agents:

docbin markdown            # print the reference to stdout
docbin markdown --web      # print this page's url