buildonce.app
MCP server

Give your AI agent
a real design tool.

BuildOnce runs a Model Context Protocol (MCP) server at https://buildonce.app/v1/mcp. Connect Claude, Cursor or any MCP client and your agent can browse templates, design new ones against your brand kit, render images, PDFs and videos, and schedule social posts — 36 tools, signed in with OAuth, inside your own workspace.

Start freeRead the docs
Who it's for

Who uses MCP server for AI agents

People working in Claude

Ask for "a launch post in our brand, 1080×1080" and get a real template and a rendered file, not a description of one.

Developers building agents

A standard MCP endpoint over streamable HTTP, with OAuth 2.1 discovery, for any client that speaks the protocol.

Marketing teams

An assistant that knows your colours, fonts and logo, and can post the result to your connected accounts.

How it works

Three steps

  1. 01

    Add the server

    In Claude: Settings → Connectors → Add custom connector, with https://buildonce.app/v1/mcp. Other clients take the same URL.

  2. 02

    Sign in and allow access

    Your client finds the OAuth endpoints itself and opens BuildOnce to sign in and choose the workspace.

  3. 03

    Ask in plain language

    The agent calls get_brand_kit, create_template, render_template and the rest, and shows you the result.

Connect any MCP client

Claude.ai and Claude Desktop add it as a custom connector. Cursor and other clients take the server URL in their MCP config; OAuth does the rest.

mcp.json
{
  "mcpServers": {
    "buildonce": {
      "url": "https://buildonce.app/v1/mcp"
    }
  }
}
What you get

What MCP server for AI agents does

It knows your brand

get_brand_kit hands the agent your palette, fonts, logos and style guide, and update_brand_kit can fill it in from a brief.

It designs, not just fills

Agents write full design documents — pages, layers, animation — with drafts, versions and a free watermarked preview before a real render.

It publishes

Schedule, publish, edit and retry posts on your connected social accounts, and check each platform’s requirements first.

It stays accountable

Every agent render bills to the workspace and shows in the render log; the OAuth access is scoped and you can revoke it.

Limits and pricing

What to know before you build

  • 36 tools: templates, drafts and versions, brand kit, assets, stock photos and videos, rendering, social posting and video ads.
  • OAuth only — OAuth 2.1 with PKCE and dynamic client registration. API keys do not work on the MCP endpoint.
  • Renders cost the same credits as the API: 1 per image or PDF page, 1 per started second of video. Previews are free.
  • Each connection acts in the one workspace chosen at sign-in.
See plans and pricing →
FAQ

MCP server for AI agents questions

Short answers to what people ask most. The documentation covers every endpoint, tool and limit.

Read the documentation →

https://buildonce.app/v1/mcp. It speaks the Model Context Protocol over streamable HTTP and signs you in with OAuth 2.1.

In Claude.ai or Claude Desktop, open Settings → Connectors, choose Add custom connector, name it BuildOnce and enter https://buildonce.app/v1/mcp. Click Connect and allow access on the BuildOnce screen that opens.

Any MCP client that supports remote servers over HTTP with OAuth: Claude.ai, Claude Desktop and Cursor are documented, and other clients connect with the same URL.

List, create, edit, duplicate and organise templates; read and update the brand kit; upload assets and search stock photos and videos; render images, PDFs and videos; schedule and publish social posts; and turn a product page into video ads.

No. The MCP endpoint is OAuth-only, so every agent connection is signed in by a person and can be revoked. API keys are for the REST API.

No separate fee. Renders made by an agent use the same render credits as any other render, and previews are free.