Design UI with your coding agent.
Experiment with live UI without cluttering your repo with throwaway prototypes.
Private by design.
Your agent makes as many variants as you like, and your project doesn't change. They stay on your Mac, in Sneak Peek's own folder. Sneak Peek never uploads them, or your code.
Your project
~/code/your-app
0files changed
As you left it
git status: clean
Sneak Peek
pricing-card
0variants made
Works with the agent you already use.
Claude Code and Codex work with Sneak Peek as they are: signed in as you, on the plan you already pay for. Sneak Peek is free.
Every pixel is your code.
Click anything to see which file it comes from. Drag a slider to try a corner radius or a spacing, and watch it change. Keep what you like, and your agent writes it into the code.
Pro
For people who ship.
$12 / month
Choose ProClick an element
pricing-card/index.tsx
<Card
radius={12} padding={20}
>
Others draw your UI. Sneak Peek runs it.
Design tools redraw or copy your interface, and someone translates it into code later. Here there is nothing to translate. Compared in October 2026.
PaperOn the canvas
Your project's code, running
Its own design layers, drawn as HTML and CSS
Into your code
Nothing to do. It already imports from your repo
Copy as React or Tailwind, or your agent reads it over MCP
AI cost
Free. Uses the agent you have
Free for 100 MCP calls a week, Pro from $16 a month
| Sneak Peek | Paper |  Magic Patterns | Claude Design |  Pen.dev | |
|---|---|---|---|---|---|
| On the canvas | Your project's code, running | Its own design layers, drawn as HTML and CSS | A React prototype its AI writes, run in its cloud | A prototype Claude makes, styled from a design system it reads from your code | Design layers in a .pen file |
| Into your code | Nothing to do. It already imports from your repo | Copy as React or Tailwind, or your agent reads it over MCP | Your agent rebuilds it over MCP, or sync it to a new GitHub repo | Hand it off to Claude Code, which builds it in your repo | Export HTML and CSS, or your agent writes it |
| AI cost | Free. Uses the agent you have | Free for 100 MCP calls a week, Pro from $16 a month | Free monthly credits, then from $17 a seat a month | Counts toward your Claude plan's limits | Uses your agent. Free 5 days a month, Pro from $16 a month |
Questions.
Is it free?
Yes. Sneak Peek is free to download and use. Claude Code or Codex runs on your own plan, as it always does.
Does my code leave my Mac?
No. Prototypes live on your Mac and import components straight from your repo. Sneak Peek never uploads your code.
Will it change my repo?
No. Prototypes live outside your project, in the app's own folder. Nothing in your repo changes unless you ask your agent to build the winner into it.
Which projects work?
React web projects on Next.js or Vite, with or without Tailwind. React Native is not supported yet.
What do I need?
A Mac with Apple silicon on macOS 14 or later, and Claude Code or Codex. Google Chrome helps your agent take screenshots of your prototypes when the app is closed.
Do I have to sign in?
No, you can continue as a guest. Signing in with GitHub or Google tells me who is using it, so I can reach you about it. Sharing usage is optional either way, and you can turn it off in Settings. Read the privacy page