Connect Nickbox to ChatGPT

ChatGPT can use Nickbox through a custom connector in developer mode, so it reads every inbox you connect, by nickname.

Before you start

• A Nickbox account with at least one inbox connected.
• Your MCP URL: https://nickbox.io/mcp here; the real one is in the dashboard under Connect.
• ChatGPT Plus or Pro. Custom MCP servers on these plans work in read-only mode, which matches Nickbox. On Business, a workspace admin must enable developer mode and custom connectors first.

A note on ChatGPT's own Gmail connector

Press coverage reports that since August 2026 ChatGPT can connect several Gmail accounts natively, with permission to send mail. If ChatGPT is the only assistant you use and you are comfortable with that permission, the built-in option may be all you need. Nickbox is read-only, and gives Claude, Gemini, Cursor and ChatGPT the same inboxes under the same nicknames.

Steps

1. In ChatGPT, open Settings and look for Apps or Connectors, then the advanced options.

2. Turn on Developer mode. On Business, ask your admin if you cannot see it.

3. Create a new custom connector. Name it Nickbox and paste:

   https://nickbox.io/mcp
   

4. Choose OAuth as the authentication method. Nickbox registers the client automatically.

5. Click Create, then Connect, and approve read-only access with your Google account on the Nickbox screen.

6. In a new chat, enable the Nickbox connector from the tools or developer mode menu.

Menu names in ChatGPT change often, so yours may differ a little from these.

Check it works

list my inboxes

ChatGPT should call list_accounts and show your nicknames. Then try Search personal for flight confirmations.

Troubleshooting

• No developer mode option. It depends on your plan. On Business or Enterprise an admin has to turn it on in workspace settings.
• The connector fails to create. Check the URL ends in /mcp and uses https://.
• ChatGPT does not call Nickbox. Enable the connector in the chat, or name it in your message: "Use Nickbox to list my inboxes."
• Google says the app is blocked. A Workspace admin policy is in the way. See the Workspace admin guide.
• Write tools are missing. That is intended. Nickbox only reads mail.