How does Second Brain work?

Second Brain works by connecting to your existing tools via the Model Context Protocol. It stores your data in a Cloudflare D1 database and Vectorize index, and uses AI to synthesize answers, detect contradictions, and surface patterns.

Is Second Brain free?

Yes, Second Brain is free and open source. It runs on the free tier of Cloudflare, and there is no usage meter or per-item billing.

Where is my data stored?

Your data is stored in your own Cloudflare account. Second Brain deploys into Cloudflare under your login, and the database, search index, and AI all run in there. The developers cannot read your data.

Which tools does Second Brain integrate with?

Second Brain integrates with Claude Desktop, Claude Code, ChatGPT, Cursor, Windsurf, and anything else that supports the Model Context Protocol. It also has integrations for Obsidian, iOS Shortcuts, and a CLI.

Can I self-host Second Brain?

Yes, Second Brain is designed to be self-hosted. It runs entirely in your own Cloudflare account, and the source code is available on GitHub under the MIT license.

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What is Second Brain?

Second Brain is an open-source, self-hosted AI memory layer that connects to your existing tools like ChatGPT, Claude, and Cursor. It stores your conversations, notes, and decisions in your own Cloudflare account, making them searchable and synthesizable across all your AI tools. With features like AI synthesis, pattern derivation, and contradiction detection, it ensures your knowledge compounds over time.

What can Second Brain do?

AI Synthesis
Answers built from saved notes, not raw entries, with sources listed.
Pattern Derivation
Surfaces themes you never wrote down after searches.
Search by meaning
Finds notes by meaning, not exact wording or tags.
Smart Merge
Merges near-duplicates and corrects contradictions.
Importance Scoring
Ranks memories by AI score and frequency of access.
One brain, every tool
Works across Claude, ChatGPT, Cursor, Windsurf, and more.
Web Dashboard
Browse, filter, edit, and export memories to JSON or Markdown.
Self-Hosted
Runs in your own Cloudflare account, free and open source.

Who is Second Brain for?

People who use multiple AI tools: Keep one shared memory across Claude, ChatGPT, and Cursor so context carries over instead of restarting each time.
Developers: Connect AI coding tools like Claude Code and Cursor through the Model Context Protocol to reuse saved context while building.
Privacy-focused users: Self-host the entire memory layer inside your own Cloudflare account so no data is processed on external servers.
Note-takers and researchers: Use semantic search and AI synthesis to surface patterns across saved notes without manual tagging.