Editor

OpenWriter uses Tiptap 3, a ProseMirror-based rich text editor that stores documents as plain .md files on disk.

Formatting

Full markdown formatting support:

  • Headings (H1-H6) with markdown shortcuts (# , ## , etc.)
  • Bold, italic, strikethrough, inline code
  • Blockquotes, ordered/unordered lists
  • Code blocks with syntax highlighting
  • Tables with row/column operations
  • Horizontal rules, links, images, task lists
  • Bookmarks and a heading navigator for long documents

Appearance

  • Light and dark modes
  • 9 typefaces: Charter, Source Serif, Crimson, Baskerville, Literata, Inter, Grotesk, DM Sans, Plex Mono (bundled, no font CDN)
  • 4 canvas styles: Seamless, Outline, Page, Paper
  • 4 spacing presets: Default, Web, Blog, Butterick
  • 3 sidebar views: Files, Timeline, Board

Keyboard shortcuts

Standard formatting shortcuts work as expected (Ctrl+B, Ctrl+I, etc.). Markdown shortcuts are supported inline — type # to create a heading, - for a list item, > for a blockquote.

Pending change review

When an AI agent makes changes, they appear as colored decorations:

  • Green — inserts (new text)
  • Blue — rewrites (modified text)
  • Red — deletions (removed text)

Navigate with j/k, accept with a, reject with r. Accept all with A, reject all with R. Pending changes survive a restart, and Focus mode lets you review without the side panels.

Author attribution

Toggle Voice in the right rail to tint each block by who wrote it: you, an agent, or both. Hover for the split (for example “68% you · 29% agent”). Accepting an agent’s change keeps it marked as the agent’s. The Versions panel shows history as attributed commits with one-click restore.

Agent marks

Select text, right-click, and leave feedback notes for your agent. The agent sees these marks via MCP tools and can respond to your direction.

Auto-save

Documents auto-save with server-side mutation validation. Corruption guards prevent accidental data loss (30% node count threshold).

Export

Export any document to Markdown, HTML, DOCX, or PDF. Manuscripts also export to EPUB.