Your AI Thinking Partner

The web app for OneBrain — your whole vault, agent chat, and rich previews in the browser.
_{No Obsidian required · Preact + Vite · talks to the onebrain serve daemon · one build, every platform.}

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OneBrain WebUI

The web app for OneBrain, built for everyday ease of use: open a browser and your whole vault is there — notes, live agent chat, search, tasks, and rich previews — on any platform, one build everywhere.

It replaces and enhances Obsidian: you don't need Obsidian installed to use OneBrain at full function. Everything the vault workflow needs lives here — reading and editing notes, wikilinks, an in-app webview for external links, PDF/Office/diagram previews, and the agent itself.

Built with Preact + @preact/signals + Vite + TypeScript. Talks to the onebrain daemon (onebrain serve) over a small JSON API — transport-agnostic, so the same build runs against a local or a remote daemon.

Status

🟢 Shipped — embedded in the onebrain CLI (v3.3.10+). A release onebrain bundles this build and onebrain serve mounts it at /. Working today:

• CmsShell — rail · Explorer · reading view · chat dock with live agent chat (streamed over POST /api/chat)
• Reading view — markdown (callouts, mermaid, KaTeX, footnotes) · syntax-highlighted code with a line-number gutter · rich previews for PDF, Office docs (docx/pptx/xlsx), images, audio/video, Jupyter notebooks, CSV, SVG, draw.io
• Editor — CodeMirror 6 live-preview editor + the PUT write path
• qmd search panel — two-tier: keyword (BM25) live, then keyword + semantic (vector) once the qmd index is available; falls back to filename/path search otherwise
• HttpDaemonClient over the vault JSON API (/api/config, /api/vault/tree|file|raw|search, /api/chat, …)
• One Panel contract (PanelDef.build(container, ctx)) — panels authored once against a single surface-agnostic contract
• Per-session token auth (daemon-injected window.__ONEBRAIN_TOKEN__, or ?token= in dev)

Develop

Requires a running daemon (onebrain-cli v3.3+ — brew install onebrain-ai/onebrain/onebrain):

# 1. start the daemon's HTTP surface against your real vault
cd /path/to/your/vault
onebrain serve            # prints http://127.0.0.1:6789/?token=<TOKEN>

# 2. start the WebUI dev server (proxies /api → 127.0.0.1:6789)
npm install
npm run dev               # http://localhost:5173

# 3. open the dev server WITH the token from step 1:
#    http://localhost:5173/?token=<TOKEN>

Point at a non-default daemon: ONEBRAIN_DAEMON=http://host:port npm run dev.

Build

npm run build             # tsc --noEmit + vite build → dist/

End users don't build anything: a release onebrain embeds this UI and onebrain serve (no --dir) mounts it — the CLI release pipeline rebuilds + embeds the latest main on every tag, so the shipped UI always matches the release.

For local development against a live daemon, serve a fresh build directly with onebrain serve --dir dist (it injects the token into index.html, so no ?token= is needed).

License

MIT OR Apache-2.0 (permissive, dual) — part of OneBrain's open core. See LICENSE-MIT and LICENSE-APACHE in the repo root; package.json declares the same dual license. Use this project under either license, at your option.