MCP
home3dplan MCP Server: Design Homes from Claude and ChatGPT
Connect Claude, Claude Code or ChatGPT to home3dplan over the Model Context Protocol. The assistant draws walls, places doors, windows and furniture, adds roofs, sites and services, checks and exports your project, and hands you a link to open it in the editor.
The home3dplan MCP server lets an assistant work in your projects the way you do in the editor: it draws on the plan, and the rooms, the 3D model and the drawings follow. You describe the house in a conversation; the assistant calls the tools; every change is a saved revision you see at once in the editor, where you render, adjust and continue.
The server is at `https://mcp.home3dplan.com/mcp`. It speaks the Model Context Protocol over Streamable HTTP and signs you in with OAuth, so the assistant acts as you and only in projects you are a member of.
What an assistant can do
**Projects**: list, create and open your projects, read a storey’s plan, and give you the link that opens a project on a storey and a view.
**The building**: draw and change walls, place doors and windows, name rooms, add and set storeys, add a roof, set materials, and run any editor command.
**Furniture, site and services**: search the catalogue and place furniture, add fences, trees and landscape blocks, lay out a site from a brief, and generate the services of a storey.
**Files and checks**: export IFC, DXF, DWG, the PDF plan sheet and the schedules into the project’s files, import a DXF, DWG or SVG drawing, turn drawn lines into walls, and run the editor’s checks.
**Deep research**: search and fetch over your projects and the documentation, for assistants that research before they answer.
Every tool is described on its own page: [all tools](/mcp/tools).
How access works
1. You add the server to your assistant ([Claude](/mcp/claude), [Claude Code](/mcp/claude-code), [ChatGPT](/mcp/chatgpt)).
2. The assistant sends you to a home3dplan page where you sign in and see what it asks for: reading your projects, changing them, and saving exports into them. You allow or cancel.
3. From then on the assistant acts as you. It sees the projects you are a member of and can change the ones you can edit. Viewers’ projects stay read only.
4. Your profile page lists every connected assistant. Revoke one there and its access ends within a minute. Removing the connector in the assistant ends it too.
Tip: the assistant keeps nothing of yours on our side. The server logs which tool was called, by which account and how long it took, and counts your calls per month. Your conversation stays with the assistant.
How the tools behave
**One call, one revision**: a tool that changes the project saves once, at the next revision number. If the project changed in your editor meanwhile, the call is refused as a conflict rather than overwriting anything, and the assistant opens the project again.
**Coordinates**: the plan is in millimetres, x to the right and y up the page; the site, the furniture and the 3D model are in metres. The assistant is told this, so you can speak in metres or feet and it converts.
**No rendering by the assistant**: it gives you the editor link instead. The editor renders on your device, in the quality you choose, and you can adjust before you do.
**Limits**: results are kept under the assistants’ size limits, and a call finishes within the assistants’ time limits. A person can make sixty calls a minute.
What it costs
During the preview the server is open to every home3dplan account at no charge; the free plan allows three thousand changes a month through assistants. Usage is counted so that pricing can be decided on what people do. Exports through the server will need a paid plan when plans are enforced; the [changelog](/mcp/changelog) will say when.
Connect an assistant
- Claude: Add home3dplan as a connector in Claude on the web or in the desktop app.
- Claude Code: One command adds the server to Claude Code; sign in from the session.
- ChatGPT: Create the connector in ChatGPT and sign in with your home3dplan account.
Reference
Read next
Frequently asked questions
Which assistants work with it?
Claude on the web and in the desktop app, Claude Code, and ChatGPT. Any client that speaks the Model Context Protocol over Streamable HTTP and signs in with OAuth can connect; the server supports dynamic client registration and client ID metadata documents.
Does the assistant see my conversation, or do you?
The assistant sees your conversation, as it always does. home3dplan sees only the tool calls it makes and answers them; it keeps the tool name, your account and the timing, not what you said.
Can the assistant render a photo of the house?
No. It gives you the link to the project in the editor, where you render on your own device in the quality you choose. This keeps the server light and lets you adjust before rendering.
What if it draws something wrong?
Every change is one revision in the project’s history. Open the editor and undo it, or ask the assistant to change it. Nothing is overwritten without a saved revision behind it.
How do I stop an assistant?
On your profile page, under Connected assistants, press Revoke. Its tokens stop working within a minute. Removing the connector in the assistant has the same effect for new calls.