Hubble.md: An Open-Source Notetaking App for You and Your Agents
Hubbele: Open-source notetaking app for you and your agents
I built Hubble.md as a free, open-source notepad that works seamlessly for both humans and AI agents. Backed by Markdown and HTML, it offers the familiar writing experience of Notion or Apple Notes while keeping your data in simple, accessible files. Whether you are logging travel notes in Kyoto or cooking recipes at home, this tool ensures your ideas are organized and ready for your digital assistants.
The same writing experience you're used to from Notion or Apple Notes, backed by Markdown files.
- dewey
I'm trying to understand why this can't just be a folder on your disk. Agents know how to use "ls" and "cat" so I guess I'm missing something.
- flippyhead
I feel like there's not enough content on the landing page to help me understand why I need yet another notetaking app. The burden of proof is high given how many of these there are.
- shreddude
I’ve been waiting for an app like this to be developed! .md files can be opened from Finder! The tree file view is just like I’m used to with Obsidian! Frontmatter support! There’s even an editor toolbar. Almost everything on my wishlist for a Markdown editor, except for Mermaid rendering.
Since this project uses such good agentic engineering practices, I was able to use Claude Code to add support for Mermaid diagram rendering and produce my very own local build on Mac, all in about 30 minutes.
Thank you! Hubble+cmux gets me close to the agentic IDE I’m working towards.
- FailMore
I think that is a really nice implementation. A few questions:
Can you easily share lists or pages or is it all local? (Is there a cloud element to it)
What are the most useful examples you’ve personally found when it comes to using the HYML component?
I built https://smalldocs.org for my agent’s Markdown needs. I extended it so it can render complex formats: Mermaid diagrams, charts, in-document slides and even in-document spreadsheets. It gives your agent a good selection of formats to express itself as it helps you understand whatever topic you’re looking into.
Here is a sample document: https://smalldocs.org/blogs/what-is-a-smalldoc
I publish anonymous analytics here: https://smalldocs.org/analytics
- xn--yt9h
Genuinely curious, maybe I'm missing something. What makes this more "agent-ready" than Obsidian .md files on disk or even something like .org files?
I can let my agent edit those files all the same + there's better integrations and knowledge readily available on these.
I can tell my agent to edit the Obsidian Markdown just like that, but I can also tell it to create a full-on notebook with backlinks and DataView queries. I can tell my agent to create logically complex .org notes with code blocks and references.
To me, Hubble just seems like a Markdown editor, based on the premise that agents are able to edit local files.