Second Brain
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A thought saved here.
A useful answer there.

Second Brain gives your connected tools a common place to remember. Each tool can add context and retrieve what matters for the conversation you’re having.

Your toolsSave useful context
Second BrainStore, connect, retrieve
Your next conversationStart with context

Save what’s worth keeping

A decision. A project update. A preference you’re tired of explaining. Ask a connected AI tool to remember it, or capture it from the dashboard, your notes, or another configured source.

The client instructions included with Second Brain tell supported AI tools to remember important context and recall it when it’s relevant. You can also ask explicitly: “Remember that the website launches on Friday.”

Connecting a tool gives it access to your brain. It does not import that tool’s entire chat history. Automatic capture depends on the client following its instructions, or on an integration you’ve configured.

Keep a usable memory

Second Brain indexes memories for search by meaning. It checks for duplicates, classifies what was saved, and builds connections between related entries.

You can append an update to an existing memory, replace something that’s no longer true, or link entries yourself. Memories can carry a source and a time history, so recalled context has somewhere to point back to.

AI-assisted organization can make mistakes. Your dashboard lets you inspect and correct what’s stored.

A woman writes in a notebook at a kitchen table, laptop open beside her in morning light.A man rides a tram, phone loosely in hand, smiling at something he just read.

Ask in your own words

You don’t have to remember a note’s title or use the exact words you saved. Ask “When are we launching?” and semantic recall can find the website’s Friday launch decision.

Second Brain returns relevant memories to the connected client, which uses that context in its response. Relationship traversal can bring in linked decisions and updates.

Retrieval is a useful starting point, not a guarantee that every answer is complete or current. Sources and staleness hints help you check.

See an example across tools

Connect once. Keep using your tools.

The desktop app deploys Second Brain into your Cloudflare account and helps connect your clients. Claude Code and Cursor have guided setup. Other clients use your brain’s connection URL and the supplied instructions.

Every connected client talks to the same service. There’s no separate memory to copy from one AI tool to another.

Find your connection guide

For the curious: the actual architecture

A Cloudflare Worker handles requests over MCP and REST. D1 stores entries and relationships. Vectorize supports semantic retrieval, Workers AI supplies model inference, and KV supports authentication-related state.

The implementation is open source. You can inspect the capture path, retrieval pipeline, and memory tools directly.

# With the Second Brain CLI configured:
brain remember "The website launches on Friday"
brain recall "When are we launching?"

Take your context into
your next conversation.

Free, open source, and in your own Cloudflare account.

Get Second Brain