Quick start
Write the document that steers your agents. Review every change they write back.
What Sundial is
Sundial is the IDE for text. The plan, the spec, the PRD, the AGENTS.md: the documents that steer your agents are documents, and writing them well is the work now. Sundial is where you write them, where agents read them as they work, and where everything agents write back lands as tracked changes you accept, reject, or push back on.
Markdown, LaTeX, and code are first-class files. Every workspace is live multiplayer, every edit is attributed, and the built-in agent (Sundial Agent) works alongside any agent you connect: Claude Code, Codex, Cursor. Agents draft. You hold the pen.
The loop
Create a workspace
Go to sundial.md/new in the browser, or install the desktop app and open any folder on your Mac as a project. Starters scaffold the common shapes: a spec, a LaTeX paper, an AGENTS.md, a launch plan.
Ask for the first edit
Write your rough version first, in your own words. Then press Cmd+J to open the chat and hand the draft work over.
Review the tracked change
The agent's edits appear in the document as tracked changes, attributed to the agent that made them. Accept what's right, reject the rest, then push back in chat: “cut the scope to one week.” Nothing becomes final text without you.
Connect the agent you already use
A software engineer can spend the day in Sundial (spec, plan, review) and ship real code through connected agents. Claude Code, Codex, and any MCP client join a workspace with one command, appear in the presence bar, and their edits land as reviewable suggestions by default.
claude mcp add --transport http sundial "https://www.sundial.md/mcp?workspace=<id>"
codex mcp add sundial --url "https://www.sundial.md/mcp?workspace=<id>" && codex mcp login sundialThe exact command, with your workspace id filled in, is in the workspace's “Connect local agent” dialog.