Brasspage Get a free plan

Your custom GPT action, rebuilt as an MCP server.

Custom GPTs are set to retire on December 11, 2026. The "Migrate to plugin" button moves your instructions and files, but custom actions do not move. Each one has to be rebuilt, usually as your own MCP server.

Send us the action's schema. We reply with a free plan: the tools it becomes and how sign-in will work. Then $49 for the working server, up to 10 operations, as code you own.

Get my free plan What changes

Built by Tack, our AI personality. Our own MCP server runs at brasspage.com/mcp and is listed in the official MCP Registry.

What changes on December 11

The dates are the planned ones in the help center notice, and they can change. Enterprise workspaces can ask for more time.

  • Moves over: the name, the instructions, the knowledge files and connected apps.
  • Does not move: custom actions. A GPT that calls your own API, or anyone's API, stops doing it until the action is rebuilt.
  • Sign-in is different: the new setup expects no sign-in for public data, or OAuth sign-in for each user. An action that sent an API key needs a new plan for that key.

A sample plan

Sample This action and its API are made up. Your plan lists your own operations.

Action operation MCP tool Sign-in
GET /forecast get_forecast key kept on your server
GET /cities list_cities key kept on your server
POST /alerts create_alert OAuth, each user signs in

A working example

We rebuilt a small exchange rate action this way: three operations became three MCP tools on Cloudflare Workers. Connect an MCP client to the live demo, or read the code on GitHub, free to copy under the MIT license.

Price

You see the plan before you pay anything.

  1. Step 1

    Free

    Send the schema

    Email the action's schema from the GPT editor, what it does, and how it signs in today.

  2. Step 2

    Free

    Check your plan

    We reply with the tool list, the sign-in plan, and anything we cannot do, usually within one business day.

  3. Step 3

    $49 once

    The working server

    Pay below with the email you used. We send the MCP server code and a step by step deploy guide for a free Cloudflare account, usually within 2 business days.

    Pay $49 for the server

Questions

What do I get for $49?

One action, up to 10 operations, as a small MCP server with one tool per operation. It is your code, to run on your own free Cloudflare account. You add your API key there yourself, so we never hold it.

What do you turn down?

Actions that break the terms of the API they call, scraping behind a login, and anything that collects private people's data. If yours is one of those, we say so before you pay.

What if it does not work?

If the server does not work with your API, we refund the $49 in full. Terms.

More than 10 operations, or several GPTs?

Email us what you have and we quote it first. You pay nothing until you say yes.

Who builds it?

Tack, our AI personality. It reads API schemas for fun, which tells you most of what you need to know about Tack.

Are you part of the company that makes custom GPTs?

No. Brasspage is an independent studio. We only rebuild the part that does not move over.