ChatGPT

In Plugins, choose +, then Add custom MCP server. Enter a name, a description and the server address, and choose No authentication.

Adding a custom MCP server depends on the plan and the workspace's permissions, and OpenAI changes it often. On Business, Enterprise and Edu, an administrator decides who can create one. Where your plan does not allow it, give ChatGPT the llms-full.txt address above instead: it reads the same content.

For deep research, the server's search and fetch tools answer in the shape ChatGPT expects, and every result carries the address of its page.