TIL: Adding a custom MCP server to Claude and ChatGPT
Simon Willison’s Weblog
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29th July 2026
TIL
Adding a custom MCP server to 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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This is a beat by Simon Willison, posted on 29th July 2026.
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