# Adding a custom MCP server to Claude and ChatGPT

> Source: <https://simonwillison.net/2026/Jul/29/mcp-in-claude-and-chatgpt/#atom-everything>
> Published: 2026-07-29 00:13:18+00:00

29th July 2026

[TIL](/elsewhere/til/)

[Adding a custom MCP server to Claude and ChatGPT](https://til.simonwillison.net/llms/mcp-in-claude-and-chatgpt)— I've started exploring [MCP](https://modelcontextprotocol.io/) in more detail. The web chat UIs for both Claude and ChatGPT can access MCP servers but it's not obvious how to set them up. Here's what I figured out.

Connecting a custom MCP server to Claude and ChatGPT's standard chat interfaces is possible, but can take quite a few steps.

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