SIMON WILLISON · 29 Jul 2026
Adding a custom MCP server to Claude and ChatGPT
Connecting a custom Model Context Protocol server to the standard web chat interfaces for both Claude and ChatGPT is entirely possible, though the process is not immediately obvious.
Setting up these custom servers within the web chat user interfaces takes quite a few steps to complete. This functionality allows users to expand the capabilities of mainstream AI chat applications by integrating their own external tools and data sources.
Understanding how to bridge custom servers with major AI platforms matters because it enables users to move beyond default features and tailor AI interactions to specific workflows.