---
title: Writing issues
description: Draft with your agent, watch the live preview, and use the Markdown the email layout supports.
sidebar:
  icon: pen-line
---

An issue is a subject, an optional preheader and a Markdown body. Sendoff pours the body into a fixed layout with your masthead, footer, unsubscribe link and postal address (if you've set one), so the agent only ever writes the middle.

## The loop

1. **Ask for a draft**

    Give the agent your notes, links or an outline: "Draft the next issue. Lead
    with the launch, then three links I've been reading." It calls
    `create_draft` and shares a preview link.

2. **Open the preview**

    Keep it open beside the conversation. It updates about a second and a half
    after each change.

3. **Ask for changes**

    "Shorter intro." "Swap the second and third links." "Add a button to the
    launch post." The agent edits with exact find-and-replace, so the parts you
    didn't mention stay exactly as they were.

Drafts are saved on every change, so you can stop and pick up later, from the same agent or another one. Ask "what drafts do I have?" to find them.

## The preview

The preview page shows the email as it'll arrive, with toggles for:

- **Email or plain text.** Every email includes a plain-text version, generated from the Markdown rather than scraped from the HTML.
- **Desktop or mobile** width.
- **Light or dark** mode. Apple Mail and others that support dark mode get the dark version; other clients show the light one.

If the Markdown has a problem, the preview lists it with a line number and keeps showing the last version that worked, dimmed. The agent gets the same list, so it can fix the draft itself.

:::note

The preview link is the only access check: anyone with it can read the draft. Share it the way you'd share an unlisted doc.

:::

## Subject and preheader

The subject is required. The preheader is the preview text most inboxes show after the subject; without one, inboxes show the start of the body. Both are separate from the body, so don't put them in the Markdown. Ask for changes the same way: "Give me five subject options", then "Use the third."

## Markdown

Sendoff supports a deliberately small subset of Markdown, chosen to render consistently in Gmail, Apple Mail and Outlook:

````md
## A section heading

A paragraph with **bold**, _italic_, `inline code` and a [link](https://example.com).

- A bulleted list
- With a second item

1. A numbered list
2. With a second item

> A quote.

![A screenshot of the new dashboard](https://example.com/dashboard.png)

::button[Read the launch post]{href="https://example.com/launch"}

:::callout[Heads up]

Callouts stand out from the text, tinted with your accent color.

:::

```js
console.log("Code blocks keep their formatting.");
```

---
````

| Supported                                       | Not supported         |
| ----------------------------------------------- | --------------------- |
| `#`, `##` and `###` headings                    | `####` and deeper     |
| Paragraphs, bold, italic, inline code           | Raw HTML              |
| Bulleted and numbered lists, blockquotes, `---` | Tables, footnotes     |
| Links to `https`, `http` and `mailto`           | Reference-style links |
| Images from `https` URLs, with alt text         | Frontmatter           |
| Code blocks, buttons, callouts                  |                       |

A few details:

- **Images** need alt text, and an image on a line of its own spans the full width. Host images anywhere public over HTTPS; Sendoff doesn't host them yet.
- **Buttons** go on a line of their own: `::button[Label]{href="https://…"}`.
- **Callouts** start with `:::callout` (with an optional title in brackets) and end with a line containing just `:::`.

## Look and feel

The layout is fixed, but your settings fill it in. Ask the agent to change any of them:

- **Name** in the masthead, or a **logo** in its place: "Use my logo at https://example.com/logo.png, 120 by 32", with an optional dark-mode version.
- **Accent color** for links, buttons and callouts: "Make the accent #ff0066". Sendoff adjusts it where needed so text stays readable, in light and dark mode.
- **Footer links**: "Add my GitHub and X links."
- **Description** for the signup page.

Changes show in the preview straight away. See [Settings](/docs/reference/settings) for every field.