Hubble: Open-source notetaking app for you and your agents | Hacker News

Hubble, an open-source note-taking app for both humans and AI agents, drew skepticism on Hacker News over how it stands out in a crowded market.

Commenters compared it with Obsidian, tldraw, Excalidraw, Draw.io, and other note systems, questioning whether Hubble offers enough differentiation.

A major theme was agent usability: people debated how well Markdown, MCP, REST APIs, and CLI tools can make notes accessible to AI workflows.

The discussion reflects two trends at once: a saturated note-taking landscape and rising demand for notes that can be read and acted on by AI agents.