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Agent-ready apps

Let your users connect ChatGPT to your app

Agent-ready apps: make the app you build with the SDK ready for ChatGPT. Your users add your app's MCP server to ChatGPT, sign in on your hosted page and approve it, and ChatGPT acts as them, never as more.

How your users add your app to ChatGPT

Give your users your app's MCP address. npx buildbase agent install --url <your MCP address> prints the setup for each AI tool, ChatGPT included, with your address filled in.

  1. In ChatGPT, your user adds a remote MCP server: Plugins > + > Add custom MCP server. They use your app's MCP address, https://app.example.com/api/mcp in these examples.
  2. Sign in. Choose OAuth when you create the server, accept the warning, and ChatGPT opens the sign-in page. In a chat, type @ and pick the server.
  3. Your hosted sign-in page opens. Your user signs in and approves the consent screen, which names ChatGPT and what it asks for.
  4. ChatGPT can now use your tools, as that user and with that user's permissions.

The plan it needs

Full MCP needs ChatGPT Business, Enterprise or Edu, on the web; Pro gets read and fetch only. On Business only admins and owners add a server. This comes from OpenAI's help center, so check the current list in ChatGPT before you start.

How sign-in looks in ChatGPT

Choose OAuth when you create the server, accept the warning, and ChatGPT opens the sign-in page. In a chat, type @ and pick the server.

What is different in ChatGPT

  • ChatGPT connects from its own servers, not from your user's computer, so your MCP server must be on public HTTPS. A server on localhost, a private network or behind a VPN is out of its reach.
  • Your server's built-in tools are read-only until you allow changes. Turn single tools on or off on the server's details page. Any tool not marked read-only counts as a write, and ChatGPT asks before a write by default; you can remember a choice for the rest of a conversation.

If it does not work in ChatGPT

ChatGPT cannot register or sign in
Turn on Let agents register themselves, with a base client, in the console under Authentication, then Agent readiness. ChatGPT registers its own client the first time it connects.
ChatGPT does not connect
ChatGPT connects from OpenAI's servers, so the address must be public HTTPS, with the /mcp path. Expand a tool call in the chat to see its input and output.
ChatGPT needs to sign in again
Open the server in Plugins and choose Refresh after anything changes on the server, then start a new conversation.
Check your server the way ChatGPT will
Run npx buildbase agent doctor --url <your MCP address>. It walks the first contact a client makes (the sign-in challenge, the metadata, redirects, a stable tool list) and exits 1 when a check fails.

Frequently Asked Questions

Which ChatGPT plan do your users need?

Full MCP needs ChatGPT Business, Enterprise or Edu, on the web; Pro gets read and fetch only. On Business only admins and owners add a server. This comes from OpenAI's help center, so check the current list in ChatGPT before you start.

Does my MCP server need to be public for ChatGPT?

Yes. ChatGPT connects from its own servers, so the address must be public HTTPS; allow its addresses if you filter by IP.

Can ChatGPT change data in my app?

Only through tools you allow, and only as the user who connected it. The built-in tools are read-only by default, and a tool that needs extra scopes is hidden until the user grants them.

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