Editing Blog/2025-10-17/Custom GPTs (section)

=== Notion MCP ===

This is a pretty reasonable use-case for an LLM, and at first I thought it must surely already have been built. In fact, [https://developers.notion.com/docs/get-started-with-mcp Notion does have a remote MCP] that you can use OAuth to authenticate into. This is a pretty good start, and you can then create a Custom GPT that reads from Notion pages and provides information and so on.

Two things that went wrong with this are:

# On read, it scans far too many pages to get to the relevant one
# It doesn't seem to want to write anything

The former is annoying because it makes everything rather slow, but the latter renders things useless. The Notion MCP page says that it should be able to read and write but when I follow the Notion MCP instructions to install it on ChatGPT in either Sync or Deep Research / Agent mode the LLM insists that it cannot write data.