Claude Desktop MCP website builder: build in the chat, check the page before it ships
Anticode's remote MCP server works in the Claude desktop app the same way it does on claude.ai: connect it once as a custom connector and every chat can reach your projects. What the desktop app adds to the routine is room. The page preview renders inside the conversation at a readable size, so you can review a change next to the discussion that produced it.
One connector, every Claude app
You don't install anything on your computer for this, and there's no local configuration file to edit. Anthropic's custom connector guide explains that remote connections are brokered through your Claude account and made from Anthropic's servers, and that Claude Desktop supports them. So the connector you add in Claude's settings, on the web or in the app, is the one the desktop app uses.
- In Claude's settings, find Connectors and choose Add custom connector.
- Name it
Anticode, enterhttps://anticode.dev/mcpand add it. - Choose Connect. Your browser opens Anticode's consent page; approve read and write, or narrow it to read-only.
- In a desktop chat, switch the connector on from the + menu.
What the preview actually is
Ask Claude to preview a project and it calls preview_project. Anticode renders the page with its design engine exactly as it would publish and returns it in a form that Claude's interface, as an MCP Apps host, draws inside the chat. MCP Apps is the protocol extension, developed with maintainers from Anthropic and OpenAI, that lets a server provide a small sandboxed interface to the host, as described in the MCP Apps announcement.
- A header with the page's name, its design system, and whether it's published. If it is, an Open site button asks Claude to open the live address.
- The page itself, in a frame about 640 pixels tall that you scroll inside.
- Nothing runs. The page sits in a nested frame with an empty sandbox: no scripts, no forms, no navigation, matching the published page's own policy. Only a tiny bridge script talks to Claude's window, and it ignores messages that don't come from it.
- The model doesn't read the HTML. The page travels in the tool result's metadata to the interface, and Claude itself receives a short summary: name, design, size, published or not. Your page doesn't eat into the conversation's context.
Previews are free and private: nothing is published and nothing comes off your allowance.
A good desktop routine
- Describe the change in plain words: "Make the hero quieter and move prices above the reviews."
- Let Claude decide whether it's a free change (theme, order, colour) or one needing the model, in which case it quotes the cost first and waits for your yes.
- Ask for a preview. Read it at the size a visitor would.
- Ask for corrections in the same thread until it's right.
- Say "publish it". The page goes through Anticode's security gate as it would from the builder, and Claude reports the live address.
If you also keep the builder open in a browser, it redraws when Claude changes the project and offers an undo, so you can watch both at once.
What stays out of reach
The connector can't upload or delete files, delete projects or your account, or touch your password, email or billing. Form submissions it reads are labelled as untrusted content, because a stranger wrote them. To cut access, disconnect Claude on anticode.dev/mcp; that ends it at once.
Limits
- The preview is one page. On a site with separate pages, it shows the page as rendered; open the builder for the rest.
- CMS data sections aren't filled in the in-chat preview. Publishing through MCP does render them from your entries, so check those sections in the builder before you publish.
- Hosts differ. The in-chat preview needs an MCP Apps host. Where it isn't supported, Claude still gets the text summary.
- Photos and videos are added in the Anticode app, not through the chat.
Troubleshooting
- The preview says "No page to show yet"
- The project hasn't been built. Ask Claude to quote and run a build first.
- No Open site button
- The project isn't published yet; the button only appears for a live site.
- The connector doesn't appear in a new chat
- Switch it on from the + menu; connectors are enabled per conversation.
- Write tools fail
- You approved read-only. Disconnect and connect again with write access.
Setting up on the web is covered on the Claude connector page, and the full tool list is on the MCP server page. If you'd rather run builds from a terminal, see Claude Code.
Questions people ask
Do I need to edit claude_desktop_config.json?
No. That file configures servers that run on your own machine. Anticode is a remote server, added as a connector in Claude's settings.
Is the preview the real page?
It's the page rendered by the same design engine that publishes it, before publishing. Forms and links are inert in the preview.
What if I'm editing the same project in the builder?
The open builder notices the change Claude made, redraws the page and offers an undo, so neither of you silently overwrites the other.