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Quickstart

Connect an MCP server and test the resulting plugin in ChatGPT Work.

Plugins extend and customize ChatGPT and Codex. They can add capabilities, connect to external services, or both. A plugin can include skills that provide instructions and resources, an MCP server that exposes tools, or both.

ChatGPT and Codex share one universal plugin directory. Public plugins are published once and become discoverable from supported surfaces in both products.

This tutorial creates a personal plugin by connecting an MCP server. By the end, you will find the plugin in your personal Plugins directory and invoke its tool from ChatGPT Work on the web. Custom UI is optional and is not part of this quickstart.

This quickstart uses a public example MCP server at https://tinymcp.dev/api/moldy-aloof-zettabyte/mcp. It exposes a read-only roll_dice tool and does not require authentication.

Connect your MCP server

First, connect your MCP server with Add custom MCP server:

  1. Go to ChatGPT Plugins.
  2. Select the plus button, then Add custom MCP server.
  3. Enter a name and use https://tinymcp.dev/api/moldy-aloof-zettabyte/mcp as the Server URL. Select No authentication for Authentication.
  4. Review the risk warning and select I understand and want to continue.
  5. Select Create as a plugin.

Test the plugin

  1. Go to your personal plugins. The plugin you created from the MCP server should appear there.
  2. Open the plugin and select the plus button to install it.
  3. Return to the ChatGPT homepage.
  4. At the top of the homepage, switch the tab from Chat to Work.
  5. Start a new Work chat. In the prompt box, type @ and select your plugin to invoke it directly.
  6. Ask the plugin to roll one 20-sided die. Confirm that it calls roll_dice once with sides set to 20 and returns one value from 1 through 20.

Test several realistic inputs, including different die sizes, invalid values, and requests that should not call the tool. Refine the tool metadata when the wrong tool is selected or its arguments are inconsistent.

Add more capabilities

Add more focused tools when the use-case inventory calls for them. To package reusable instructions with the MCP server, continue with Build skills and Package your plugin. If a workflow benefits from visual interaction, continue with Add UI to your MCP server. UI remains optional.

Publish the plugin

When the plugin is ready for other people, review the complete plugin build guide. To publish it publicly, use the plugin submission portal.