MCP website builder for Claude, ChatGPT & Codex

Connect Claude, ChatGPT, Codex or another MCP client to build websites and edit them through your own iter0 account. Start a build, then use its run ID to check progress. When it finishes, use the status tool to get a link to the design in My designs, or request the page's HTML if it could not be saved.

Install the iter0 MCP/mcp ->

Agent workspace

Claude/ChatGPT/Codex

Agent prompt

Create a launch page for a compliance automation startup. Use our existing site for language, upgrade the design, and save the final HTML locally.

iter0_create_site01

Create, clone, or upgrade a site through the iter0 builder API.

iter0_edit_site02

Apply bounded edits to generated HTML without asking the agent to redesign the whole page.

iter0_get_site_status03

Check a running build and open its saved design when ready.

MCP invocation

streaming

iter0_create_site

{
  "cloneUrl": "https://customer-site.example",
  "prompt": "Use their content. Improve the structure."
}

research

Industry context and reference fit

build

Generated HTML and preview artifact

proof

Saved output path for agent review

Site saved to ~/.iter0/sites. Credits charged to the owning iter0 account.

Connect Claude, ChatGPT or Codex.

The server is at the address below. Claude Code and Codex sign in with an iter0 API key: create one, then set it as ITER0_API_TOKEN in your shell. ChatGPT signs in to your iter0 account instead.

Server URL

https://iter0.com/api/mcp

Claude Code

Run this once in your terminal. The key is saved in Claude Code's settings.

claude mcp add --transport http iter0 https://iter0.com/api/mcp --header "Authorization: Bearer $ITER0_API_TOKEN"

Codex

Add this to ~/.codex/config.toml. Codex reads the key from your shell each time it starts.

[mcp_servers.iter0]
url = "https://iter0.com/api/mcp"
bearer_token_env_var = "ITER0_API_TOKEN"

ChatGPT

Open chatgpt.com/plugins, select the plus button, then Add custom MCP server.
Name it iter0 and enter the server URL as a public endpoint.
Choose OAuth for authentication and sign in to your iter0 account.
Select Create as a plugin and check that the iter0 tools are listed.

23 tools, and what each one costs

Every tool works on your own iter0 account. Paid tools return a price quote first and start only after you confirm it.

23 tools, and what each one costs
Tool	What it does	Cost
`iter0_health`	Checks that the iter0 API is reachable. Builds nothing.	Free
`iter0_create_site`	Builds a website in your account from a brief, a reference URL you are allowed to use, or one of your Show 3 directions.	1 credit
`iter0_edit_site`	Makes one focused change to a saved design and keeps the previous page so you can undo it.	Half a credit
`iter0_get_site_status`	Checks a running build and returns the saved design when it finishes.	Free
`iter0_get_developer_docs`	Returns the links to the API docs, the OpenAPI spec, MCP setup and support.	Free
`iter0_show_three`	Prepares three draft design directions for your business to choose from.	1 credit, or your free allowance
`iter0_get_design_set_status`	Reads a Show 3 batch: its status, then the three directions with previews.	Free
`iter0_confirm_paid_action`	Starts a quoted build, edit or Show 3 after you confirm the price. Failed work is refunded.	The quoted price
`iter0_open_builder`	Opens your recent designs, search and a box to start a new site.	Free
`iter0_list_my_designs`	Lists your saved designs, newest first, with links.	Free
`iter0_get_design`	Reads one design's name, link, sections, headline and saved versions.	Free
`iter0_design_layout`	Gives the iter0 card a light copy of a page so it can outline the section you point at.	Free
`iter0_restore_version`	Puts back an earlier saved version of a site, after you confirm.	Free
`iter0_undo_edit`	Undoes the last saved edit.	Free
`iter0_check_site`	Lists problems before you share a site: missing titles, alt text, broken links, sample text and forms that send nowhere.	Free
`iter0_publish_site`	Puts a saved site live at its own name.iter0.app address, after you confirm.	Free
`iter0_unpublish_site`	Takes a live site offline and keeps the design and the address.	Free
`iter0_publish_status`	Says whether a site is live and whether the live copy is the saved version.	Free
`iter0_push_site`	Puts finished HTML pages you built elsewhere on your iter0 canvas, one frame per page.	Free
`iter0_get_canvas_feedback`	Reads comments, notes and pins, with each page's version and available positions on the canvas and page.	Free
`iter0_reply_to_feedback`	Adds a reply to a comment thread or pin. It never resolves or deletes anything.	Free
`iter0_read_canvas_page`	Reads one canvas page's HTML and version, so you can merge edits before the next push.	Free
`iter0_get_canvas_snapshot`	Returns a page screenshot with numbered feedback markers, outlines around commented elements and a legend, or a canvas overview with notes in place. Free and read-only.	Free

Credit pricing

A build costs 1 credit, an edit costs half a credit and Show 3 costs 1 credit. Publishing, checks, undo and the canvas tools are free. Free gives 3 credits a month, Hobby is $5 a month for 15 and Pro is $25 a month for 100.

Install once. Let the agent call the builder.

The MCP is a client of the production API. It uses account-owned API keys, spends existing credits, and writes generated HTML artifacts locally for verification.

Create MCP token Direct download API docs

Terminal install

Any terminal with Node

node -e "fetch('https://iter0.com/api/mcp/install/node').then(r=>r.text()).then(eval)"

Mac / Linux shell

curl -fsSL https://iter0.com/api/mcp/install | sh

Windows PowerShell

irm https://iter0.com/api/mcp/install/windows | iex

Use the Node command in PowerShell, cmd, bash, or zsh. The shell and PowerShell commands are direct alternatives. The installer saves the server locally, then prints the MCP client config. Create a iter0 token, paste it in as ITER0_API_TOKEN, and your agent can call the builder.

Put a site on the canvas.

The canvas is where people comment on your pages in iter0. Push a built site, read the feedback, see it in a snapshot, reply, then push the revision. The canvas tools are free and use no credits.

Push the pages, open the canvasUrl and read the feedback. Before editing, call iter0_get_canvas_snapshot with the designId and pageKey to see notes on that page. Reply, then push again with the expectedVersion of each page you replace.

iter0_push_site

Puts finished HTML pages on the canvas, one frame per page, up to 20. Returns a canvasUrl to open.

iter0_get_canvas_feedback

Reads comments, notes and pins, with each page's version and available positions on the canvas and page.

iter0_get_canvas_snapshot

Returns a page screenshot with numbered feedback markers, outlines around commented elements and a legend, or a canvas overview with notes in place. Free and read-only.

iter0_reply_to_feedback

Adds an agent's reply to a comment thread or pin. It never resolves or deletes anything.

iter0_read_canvas_page

Reads one canvas page's HTML and version, so you can merge their edits before a push.

The local server has its own iter0_push_site. Point it at your build folder with rootDir and it sends the pages for you.

Account-owned keys

No browser cookies, no free bypass. Agent calls authenticate through scoped iter0 API keys.

Production API boundary

The MCP calls /api/v1/sites and /api/v1/sites/edit through your iter0 account.

Local proof artifacts

Generated HTML and local output paths are written where agents can inspect them.

Founders launch in the builder. Agents launch through MCP.

Same iter0 system, two entry points: a visual builder for humans and a callable tool surface for agents.

Open builder