rapier

Rapier is a fast Markdown editor made for your phone. It has no ads, accounts or tracking. Write, draw, paint and keep notes, offline. It also works on a computer.

Get Rapier

• The Rapier app for Android. It has no internet permission, so nothing leaves your phone.
• rapier.website in your phone's browser. Add it to your home screen and it opens like an app, offline too.
• In ChatGPT or Claude: add the Rapier plugin and ask your agent to open Rapier.

Tip. Tap any paragraph to edit it. Drag the circle at the right edge to move through a long document, or tap it to see the headings.

Contents

• Start here
• Writing
• Lists
• Pictures
• Drawing
• Paint
• Tables
• Code
• Notes
• Open, save and export
• Compare
• Agents
• Where it runs
• Keyboard
• For developers and agents
• Will

Start here

1. Tap this line to edit it.
   1. The formatting bar appears with the everyday tools. + has every other command.
   2. You can type Markdown. Rapier shows it formatted as you type.
   3. Tap outside the text when you're done.
2. Tap a line in the contents to jump there. + → Table of contents adds one to any document.
3. Tick a box.
   • ☑ Open Rapier
   • ☐ Change these words
   • ☐ Tick this box
4. This document is yours to change. Undo is on the formatting bar.

Writing

Write the way you would on paper, and Rapier keeps it as plain Markdown. This W comes from one of Draw's four letter sets, traced from old books in the British Library. It is a drawing: tap it, then the brush, to change it.

Bold, italic, struck through, underlined, code, highlighted, 🟢green, 🔴red, 🔵blue, H₂O and 1^st. It is all plain Markdown, so any other Markdown app can open the file.^[1]

A quote starts with >. Use it for words from someone else, or to set a passage apart.

Note. A callout is a quote that starts with [!NOTE], [!TIP] or [!WARNING]. Apps that don't know callouts show it as a quote.

Find and replace is behind the magnifier. + → Line adds a page break for PDF and Word. Footnote, Divider and Table of contents are there too.

Lists

1. A numbered list keeps its numbers when you add, move or delete lines.
2. Put the cursor in an item and tap Nest to indent it. Resume moves it back.
   1. Numbers start again inside.
   2. Bullets and numbers can mix.
      • A bullet inside a number
      • Another one
   3. Then back out.
3. Tab and Shift Tab do the same on a keyboard.
4. A checklist is a list with boxes:
   • ☑ one you tick from the page
   • ☐ one still to do
5. A list pasted from Word or a web page stays a list.

Pictures

Add a picture (PNG, JPEG, WebP or JPEG XL), then drag it to move or resize it. Text wraps around the picture's outline, not its box. Tap a picture for its controls: the brush opens it in Draw, T changes its description, and you can rotate or fade it. Pictures are stored inside this Markdown file. Nothing is uploaded. New pictures are saved as JPEG XL, which keeps them small.

Drawing

The brush on the formatting bar starts a new drawing. SVG Brush follows your pressure and speed. A stroke that looks like a circle, box, line or arrow becomes that shape with one tap. SVG Pen (Testing) draws an even line. Choose Select, then tap a shape to move, resize, label or restyle it, or to attach an arrow that stays attached when the shape moves. The drawing is saved in the file as SVG, so it stays sharp and you can edit it later.

This rapier is a drawing too, and the words follow its outline, not its box. Tap it, then the brush, and every part is yours to move. Its grip is a line made into a tube and a rope: choose Select, tap a line, then Style → Look for a spring, rope or tube.

Paint

Raster Brush has real painting brushes: oil, bristle, marker, pencil, pen and watercolour. Paint with your finger. Rapier runs its own paint engine, so a MyPaint brush behaves as its author set it. Watercolour keeps spreading after you lift your finger, then dries. Smudge, smear, blend and erase work on paint that is already down. A painting is one picture inside the drawing, saved losslessly. You can paint into it again.

Tables

Tap a cell to edit it. Tab moves to the next cell. Add or remove rows and columns from the cell's controls. Paste cells from a spreadsheet and the table grows to fit.

Code

export function twice(x) {
  return x + x;
}

Code is highlighted offline. Text and code files open in a source editor, where the circle jumps to a line or a declaration. The eye/code switch in Settings shows the Markdown source of this page.

Notes

Open Notes from the three dots. Each note is a Markdown file shown as a card. Pin cards, colour them and sort them into sections. A note can hold a checklist you tick from its card, a reminder, a voice recording, drawings and attached files. Import brings in notes from Google Keep, Apple Notes, Evernote, Notion, Obsidian and more. Backup saves them all as one zip. Sync keeps them in your own Cloudflare account, encrypted with a key that never leaves your devices.

Tip. Back up notes you care about. A browser can clear its stored data. The Android app keeps notes in its own files, outside Android's automatic backup.

Open, save and export

Open Markdown, text, code, Word, TextPack or PDF files. A Word document becomes an editable page with its pictures. A PDF comes in as text or as pictures of its pages.

Rapier keeps a draft as you work, so a closed tab comes back. Save writes the file and, where it can, reads it back to check it. Your Markdown stays readable in every other app.

Under the three dots, Copy, Share and Export send your work as text, a web page, PDF or Word. A shared web page opens offline in any browser, and Rapier can open it again for editing.

Compare

Compare, under the three dots, shows what changed between this document and another file, with the unchanged parts folded away. Neither file changes.

- The meeting is on Monday.
+ The meeting is on Tuesday.

Agents

Use Rapier with Claude, ChatGPT or any AI agent that speaks MCP, on the document you have open. Ask it to explain, rewrite, plan or draw. It reads only the parts it needs, so it stays fast on a long document. It changes only the passage it read and can't overwrite what you are typing. Each change shows where it lands, and you keep or drop it. Undoing a change never undoes your own work. While an agent is connected, the circle says so. Tap it for status, messages and changes. Select a passage and use Ask to talk about that part.

To connect, add https://mcp.rapier.website/mcp as a connector in Claude, ChatGPT or any app that takes MCP. It needs no account and no key. In Claude Code, the Rapier plugin sets it up.

Try asking: “Draw my Saturday.” The agent lays out a diagram with numbered steps and arrows, in light and dark.

Tap a diagram once to select it. Then move or resize it like a picture, tap a label to type new words, or drag a box and watch its arrows follow.

Where it runs

Rapier is made for your phone and works the same in any browser. Use it at rapier.website, install it as an app, or keep rapier.html on a USB stick. The Android app has no internet permission. The whole editor is one file, under 2 MB.

Keyboard

Hold Ctrl (Cmd on a Mac), then:

With words selected, K adds a link. Tab and Shift Tab nest a list item, indent code or move through a table. Esc closes what's open.

For developers and agents

npx rapier-html notes.md
npx rapier-html notes.md --view draw
npm install rapier-markdown-kit
npm install rapier-embed

rapier-html opens a document in the whole editor. rapier-markdown-kit reads and writes Markdown. rapier-embed puts Rapier inside your own app. The agent tools are described in llms.txt and agents.md; the hosted connection is https://mcp.rapier.website/mcp.

Rapier is open source under AGPL-3.0-only. The Markdown kit is MIT licensed.

Will

If you work with an agent, you can say what it may do with each part of a document. Select a section, tap W on the formatting bar, then type an intent or lock the section. Rapier writes this into the document as HTML comments. Agents read them and people never see them. They travel with the file: Markdown, Word, PDF and Rapier's own web pages.