OneBrain: the open-source, self-hosted AI thinking partner for your notes. UNIFIED INTELLIGENCE
OneBrain is the open-source, self-hosted AI thinking partner for your notes and knowledge — local-first and yours forever.
Run it from your terminal with a built-in web UI — or right inside Obsidian. You teach the agent, the agent extends you, and both get sharper every session.
brew install onebrain-ai/onebrain/onebrain // NO CLOUD · NO ACCOUNT · OBSIDIAN OPTIONAL · MIT / APACHE-2.0
Built for
Synergetic Thinking.
OneBrain works your markdown as a shared workspace. Every feature exists to make you and the agent better at each other's job.
Persistent Memory
Four tiers: working, episodic, semantic, knowledge. Across every session.
Frictionless Capture
Braindump, capture, or bookmark, whichever matches your thought.
Semantic Search
Native hybrid keyword + vector search. Recall any idea in seconds.
Auto-Linking
Every new note gets wikilinks pulled from your existing knowledge graph.
Skills System
30 slash commands wrap deep workflows like /research, /distill, /search, and /schedule-add.
PARA Native
Ready-made structure for Projects, Areas, Resources, and Knowledge folders.
Beyond a
Second Brain.
OneBrain co-evolves with you. Every preference you teach sharpens the agent, and every link it surfaces sharpens you.
HUMAN → AGENT
Every correction saves to memory/. The agent remembers it next session, not next week.
AGENT → HUMAN
Captures and links your raw thoughts, articles, and meeting notes automatically. You stay on what only you can do.
Multi-Harness
Orchestration.
OneBrain orchestrates the harness you already use. Bring Claude Code, Gemini CLI, Codex, Qwen, or a raw API key, and switch any time. Your vault stays the constant; the harness is the variable.
One Vault,
All Projects.
OneBrain turns your notes into your command center: research, planning, agent memory, and project state in one place, so you stop juggling tabs and tools.
- » Read once, understand all: agent context lives in one place, never re-explained.
- » Code in repos, orchestration in vault: the agent dispatches from here to wherever the work actually lives.
- » Markdown replaces Slack, Linear, and Notion: version-controlled, AI-readable, yours forever.
Every Session
Sharpens Both.
OneBrain runs as a tight 4-step loop: it opens by loading what it knows and closes by folding new lessons back into memory — sharper every round.
- 01
INITIALIZE
Each session opens by loading your memory, active projects, preferences, and what’s due.
/daily · /resume - 02
CAPTURE
Talk to the agent in natural language. It writes, classifies, and links your thoughts in real time.
/braindump · /capture · /bookmark - 03
EVOLVE
/research and /distill grow what you know. /learn teaches the agent how you work.
/research · /distill · /learn - 04
WRAPUP
/wrapup consolidates the session; /recap promotes lessons to memory — so the next loop starts smarter.
/wrapup · /recap
30 Commands
That Think.
OneBrain ships 30 slash commands and 5 background agents: vault-aware verbs that wrap real workflows. /research builds reports, /distill synthesizes weeks of notes, /schedule-add automates them on a cron.
Self-Hosted.
Open & Yours.
OneBrain runs entirely on your machine. No cloud, no account, no lock-in. Drive it from your terminal with a built-in web UI, or inside Obsidian — your data is plain Markdown you own forever. Free and open under MIT / Apache-2.0.
SELF-HOSTED
// Terminal + built-in web UIObsidian optional · brew / npm
[ AVAILABLE_NOW ]ONEBRAIN SYNC
Vault · memory · context synced across machines · agent stays local
[ PLANNED ]Be first to know when OneBrain Sync ships.
// no spam · one email when Sync ships