visualOS

Short answer: Not officially documented in our wiki yet, but yes, other tools can read it.
Long answer: The format is deliberately boring: every board is a real folder, documents are plain Markdown, images/PDFs are ordinary files, and each folder contains a human-readable board.json (positions, texts, connections... So basically plain JSON). Each board folder is self-contained, so any tool, your self-written scripts, Obsidian, or an AI agent can read a single project folder without knowing anything else. There's also a canvas-data.json at the root, which is the app's source of truth; the per-folder files are a readable mirror.