Last weekend, I wrote a bit about using Zapier to load Notion pages as prompts to comment on other Notion pages.That worked well enough, but not that well.This weekend I spent some time getting the next level of this working,creating an agent that runs as an AWS Lambda.This, among other things, allowed me to rely on agent tool usageto support both page and block-level comments, and altogether I thinkthe idea works extremely well.

This was mostly implemented by Claude Code,and I think the code is actually fairly bad as a result,but you can see the full working implementation at lethain:basic_notion-agenton Github. Installation and configuration options are there as well.

Watch a quick walkthrough of the project I recorded on YouTube.

Screenshots

To give a sense of what the end experience is, here are some screenshots.You start by creating a prompt in a Notion document.

Then it will provide inline comments on blocks within your documenhttps://lethain.com/static/blog/2025/notion-inline-comment.png-inline-comment.png" alt>

It will also provide a summary comment on the document overall(although this is configurable if you only wahttps://lethain.com/static/blog/2025/notion-page-comment.pngatic/blog/2025/notion-page-comment.png" alt>

A feature I particularly like is that the agent isaware of existing comments on the document, and who madehttps://lethain.comhttps://lethain.com/static/blog/2025/notion-comment-replies.png

Altogether, it’s a fun little project and works surprisingly well,as almost all agents do with enough prompt tuning.