Markdown and diagrams

Agents write Markdown, so most of what you read in Happier is Markdown that has been rendered rather than shown raw. Two parts of that are worth knowing about: diagrams, and what happens when you edit a Markdown file yourself.

Mermaid diagrams

Mermaid diagrams in a transcript render as diagrams, on every client including iOS and Android.

The Mermaid runtime is bundled with the app rather than fetched from a CDN. That matters in two situations people actually hit: a machine on a restricted network still renders diagrams, and rendering a diagram never tells a third party what you are looking at. Diagram source is sanitized before rendering, and the native renderers keep their web view away from the app's network, message and navigation surfaces.

The rich Markdown editor

When you open a Markdown file in Happier's editor, you can edit it as formatted text instead of raw syntax — headings, emphasis, inline code, task lists, blockquotes, code blocks, rules and links, with Notion-style slash commands for inserting them. A formatted preview updates as you type.

It falls back to raw Markdown rather than risking your file when:

• round-tripping the document would lose content,
• the file is too large,
• or the editor bundle is unavailable on that client.

Switching between raw and rich preserves what you have written; the editor flushes pending changes synchronously at the boundary rather than letting the two views drift.

Tables, math, Mermaid diagrams and images are not yet editable in the rich view. Files containing them still open — you edit them as raw Markdown.

Related

• Git and files — browsing and editing the rest of a workspace.
• Attachments and image previews
• Navigating a transcript