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Smart Second Brain

S2B DevsS2B DevsLeo310Leo31069k downloads

Chat with an agent that knows your notes, search by meaning, and see your vault grouped into topics. Runs on Ollama, OpenAI, Anthropic, and more.

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Smart Second Brain

Your Smart Second Brain is a free and open-source Obsidian plugin that makes your vault smarter: better search, an interactive knowledge graph, and an AI assistant that actually knows your notes.

Search surfaces your notes, the graph groups them into the topics your vault is actually about, and the assistant can draw on both when answering. Search and the graph work right away with no AI provider. Connecting one unlocks the full agent. Runs on desktop and mobile.

smartsecondbrain.dev has a demo video, the features, setup guides, and documentation.

Smart Second Brain: the smart graph with the vault grouped into topics, beside a chat that reads your notes and proposes an edit

Features

  • Search that combines keyword matching with meaning, so you find the note you were thinking of rather than the one you typed (how it works)
  • Smart Graph that works out what your vault is about: notes grouped into topics from your links, your tags, and what you wrote, with nothing to maintain (how it works)
  • Agents that read and write your notes, draw charts and dashboards live from them as widgets, with skills, memory, MCP, and integrations with your other plugins

Install

Install Smart Second Brain from Obsidian's community plugins and enable it. Search and the Smart Graph work immediately, with no configuration.

Add an embedding model and pick it for search and for the graph to unlock semantic search and topics that read what your notes say, not just how they link; add an AI provider to enable the agent. See the getting started guide.

Out of the box, none of your data leaves your machine. Your notes only go to the providers you configure, and there is no telemetry — see privacy. The one other network request is a daily update check that fetches this plugin's manifest.json from GitHub and sends nothing about you; turn it off under Settings → General → Check for updates.

Contributing

  • Report a bug or request a feature here
  • Ask a question in the Q&A
  • Share a skill, agent, or workflow in Show and tell
  • Pull requests welcome. CONTRIBUTING.md has the development setup and how we handle AI-assisted contributions; AGENTS.md has the architecture, commands, and conventions

We initially built this as a university project. That's long finished, but we keep developing it in our spare time, as an experimental playground for state-of-the-art AI and as a tool for the Obsidian workflow we're passionate about. Much of the code is written with AI coding agents; we review, test, and stand behind every change, and commits and pull requests say when an agent was involved.

License

MIT

HealthExcellent
ReviewSatisfactory
About
Turn your vault into an AI-assisted second brain. Chat with an agent that searches and reads your notes, edits them with every change staged for your review, browses the web, and works with plugins like Dataview, Tasks, and Canvas. Answers are grounded in your own notes through hybrid search that fuses semantic and keyword retrieval. A smart graph groups related notes into topics automatically, revealing structure you never linked by hand — immerse into a topic or pull back for the whole picture. Search and the graph work on their own, with no AI provider configured. Connect one — Ollama or oMLX locally, or OpenAI, Anthropic, and OpenRouter in the cloud — to enable the agent. Pair a local chat model with a local embedding model and nothing leaves your machine. There is no telemetry.
AIGraphSearch
Details
Current version
2.3.0
Last updated
2 days ago
Created
3 years ago
Updates
40 releases
Downloads
69k
Compatible with
Obsidian 1.11.4+
Platforms
Desktop, Mobile
License
MIT
Report bugRequest featureReport plugin
Authors
S2B DevsS2B Devss2b-dev
smartsecondbrain.dev/
GitHubyour-papa
Leo310Leo310leo310
GitHubleo310
Xleodev310
  1. Community
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