Show HN: OpenKnowledge – open source AI-first alternative to Obsidian/Notion

What we know

We’re launching OpenKnowledge (https://openknowledge. ai/), a “what you see is what you get” markdown editor that has direct integrations with Claude, Codex, and Cursor.

The consequence

We built this because we wanted a “Google docs” like experience for writing and sharing markdown files across our team. Obsidian is the best alternative we tried, but found it doesn’t have a true “what you see is what you get” UI and it didn’t integrate well with Claude/Codex outside of community plugins.

The landscape

A MacOS app with a file navigator, the WYSIWYG editor, and link explorer

Where this fits in Signal Ledger

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The framing

Obsidian is the best alternative we tried, but found it doesn’t have a true “what you see is what you get” UI and it didn’t integrate well with Claude/Codex outside of community plugins. The agents can open an OpenKnowledge editor within their embedded web browsers for a side-by-side experience.