> ### Get Started. Deploying to Cloudflare takes only 2 Minutes - [Deploy to Cloudflare in One Click](https://deploy.workers.cloudflare.com/?url=https://github.com/rahilp/second-brain-cloudflare)
# Second Brain
[](LICENSE)
[](https://workers.cloudflare.com/)
[](https://modelcontextprotocol.io/)
> ## #3 Product of the Day on Product Hunt
>
>
You use Claude for some things, ChatGPT for others, Cursor for code. But your context — your projects, decisions, preferences — doesn’t move with you. You re-explain yourself constantly.
Second Brain fixes that. One shared memory, available in every AI tool you use.
And unlike the built-in memory inside any single app, this one is yours. It lives in your own account. No platform controls it, and no platform can take it away.
[](https://youtu.be/h0JqRM0UxHE)
[](https://deploy.workers.cloudflare.com/?url=https://github.com/rahilp/second-brain-cloudflare)
> [!TIP]
> Have a question, feature idea, or want to show how you’re using it? [Join the conversation in GitHub Discussions](https://github.com/rahilp/second-brain-cloudflare/discussions)! That’s where releases get announced and the roadmap gets shaped.
-----
## How it works
Connect Second Brain to whichever AI tools you use. Then tell it things once. It finds them later by meaning, so asking “what did I decide about the pricing model?” surfaces the right note even if you never used those exact words when you saved it.
|Tool |What it does |
|-------------|------------------------------------------------------------|
|`remember` |Store anything: ideas, decisions, project context |
|`append` |Add updates to an existing entry without creating duplicates|
|`update` |Replace an entry’s content entirely |
|`recall` |Finds memories by meaning, not exact wording |
|`list_recent`|Browse recent memories by date |
|`forget` |Delete an entry |
-----
## Save from anywhere
Memory is only useful if it actually gets filled. Second Brain connects to the tools and moments where context naturally lives.
- **CLI** — `brain remember`, `brain recall`, and more from your terminal — `npm install -g second-brain-cf-cli`
- **Obsidian** — notes sync automatically via the [community plugin](https://github.com/rahilp/second-brain-obsidian-plugin) · available in [Obsidian Community Plugins](https://community.obsidian.md/plugins/second-brain-sync)
- **iOS** — Brain Dump, Text Brain Dump, and Save to Brain shortcuts in [`integrations/ios-shortcuts/`](integrations/ios-shortcuts/)
- **Browser extension** — capture any page or highlighted text in one click via the [Chrome extension](https://github.com/rahilp/second-brain-browser-extension)
- **Bookmarklet** — lightweight option in [`integrations/bookmarklet.js`](integrations/bookmarklet.js)
- **Any AI client** — use `remember` mid-conversation, right when something matters
-----
## Quick Start
> **Before you deploy:** You’ll be asked to set an `AUTH_TOKEN` — the password your AI clients use to connect. Use a memorable phrase (`coffee-lover-2026`) or run `openssl rand -base64 32` for a stronger one. **Save it** — you'll need it in step 3.
1. **[Deploy to Cloudflare](https://deploy.workers.cloudflare.com/?url=https://github.com/rahilp/second-brain-cloudflare)** — one click, everything provisions automatically. Set your `AUTH_TOKEN` when prompted.
1. **Using Claude Code or Codex CLI?** Run one command and paste in your worker URL — it wires up global instructions *and* the MCP connection via OAuth, so your token never touches the script:
```bash
# macOS / Linux / WSL / Git Bash
curl -fsSL https://raw.githubusercontent.com/rahilp/second-brain-cloudflare/main/scripts/connect-ai-clients.sh | bash -s -- https://YOUR-WORKER-URL
```
```powershell
# Windows (PowerShell)
iex "& { $(irm https://raw.githubusercontent.com/rahilp/second-brain-cloudflare/main/scripts/connect-ai-clients.ps1) } -WorkerUrl https://YOUR-WORKER-URL"
```
1. **Using ChatGPT or Claude (desktop app or web)?** These need two quick manual steps in their UI — paste your custom instructions into their personalization settings, and add `https://YOUR-WORKER-URL/mcp` as a custom MCP connector. Each app's exact menus differ, so follow the **[per-app steps in the wiki](../../wiki/Connect-to-AI-Clients)**.
That’s it. Your memory is live and ready across every tool you connect.
```bash
# Verify it's working (replace YOUR-WORKER-URL and YOUR-TOKEN with your values)
curl -X POST https://YOUR-WORKER-URL/capture \
-H "Authorization: Bearer YOUR-TOKEN" \
-H "Content-Type: application/json" \
-d '{"content": "second brain is working", "source": "test"}'
# → {"ok":true,"id":"..."}
```
### OAuth for browser-based clients
The `/mcp` endpoint supports **OAuth 2.0** (discovery + dynamic client registration),
so any MCP client that can open a browser to authenticate connects without ever
putting a token in a config file or URL. When you add `https:///mcp`
as a connector, the client detects the `WWW-Authenticate` challenge, registers itself,
and opens the worker's hosted login
page; **enter your `AUTH_TOKEN`** there to authorize. claude.ai, ChatGPT, Claude Code
(`claude mcp add --transport http second-brain /mcp`, no `--header` needed), and
Codex CLI (`codex mcp add second-brain --url /mcp`, which detects OAuth support
and starts the login flow itself) all use this flow.
Clients that can't open a browser — e.g. `mcp-remote` in headless contexts — can still
fall back to the static token via `Authorization: Bearer `.
OAuth needs a KV namespace (`OAUTH_KV`) to store tokens and client registrations.
The **Deploy to Cloudflare** button provisions it automatically.
**Deploying manually**, follow these steps. Wrangler validates the entire config before running any command, so the order matters:
1. Remove the placeholder `[[kv_namespaces]]` block from `wrangler.toml` (the one with
the empty `id`).
1. Create the namespace:
```bash
wrangler kv namespace create OAUTH_KV
```
1. Copy the `id` from the output and add it back to `wrangler.toml`:
```toml
[[kv_namespaces]]
binding = "OAUTH_KV"
id = ""
```
> The key change is the warning to add the real `id` before running any other wrangler commands, since wrangler validates the entire config upfront and rejects an empty string.
-----
## Documentation
- [Setup Guide](../../wiki/Setup-Guide) — deploy, token setup, connecting AI clients
- [How It Works](../../wiki/How-It-Works) — semantic search, chunking, duplicate detection
- [Connect to AI Clients](../../wiki/Connect-to-AI-Clients) — Claude Desktop, Claude Code, claude.ai, iOS
- [Capture from Anywhere](../../wiki/Capture-from-Anywhere) — browser extension, bookmarklet, iOS Shortcuts, share sheet
- [Web UI](../../wiki/Web-UI) — dashboard and mobile interface
- [Obsidian Plugin](../../wiki/Obsidian-Plugin) — install, configure, sync modes
- [API Reference](../../wiki/API-Reference) — /capture, /append, /update, /list, /recall, /forget, /count, /tags, /stats, /chat, /digest, /mcp endpoints
-----
## Stack
Cloudflare Workers · D1 SQLite · Vectorize · Workers AI · KV · MCP TypeScript SDK · MIT License
All free tier at personal scale. Your data stays in your own Cloudflare account.
-----
## Star History
-----
[MIT License](LICENSE) · [Discussions](https://github.com/rahilp/second-brain-cloudflare/discussions)
