One Brain MCP server

One Brain: the memory Claude Code is missing

Every session starts from zero and forgets it all on close. One Brain gives Claude Code permanent memory, shared by the whole team. What one person records, everyone has, with the name and the date still attached.

Create your brain · Free during the open beta · Leer en español

What it looks like

Someone asks their Claude about a service they didn't build:

why does the payments worker stop retrying after 2 attempts?

That cap is deliberate, not a leftover. It was set after the duplicate-charge incident

in March.

*"Two retries on payments, hard stop. At five we double-charged 40 customers in one

night. If a queue genuinely needs more, it comes through me."*

Priya Raman · Platform · Mar 12

The answer came out of a teammate's session six months earlier. Nobody wrote a document for it.

Why it's different

Nobody writes documents. Memory gets recorded when you close a topic, so there is no form to fill in and no wiki to keep alive.

Every answer has a name and a date on it, which means you stop reconstructing intent from commit messages a year later.

Every service, client or person is a tag. Ask about one and you get everything the team wrote about it, whichever teammate wrote it.

The server itself doesn't run any model. It stores and retrieves, and the judgment stays in your Claude, on your machine.

Getting in

exists immediately, with no form to fill in and nothing to approve.

1. Sign in with Google at onebrain.prophet.lat. Your brain

1. Install the plugin in Claude Code:

/plugin marketplace add Prophet-git/one-brain-plugin
   /plugin install one-brain@prophet

Then close Claude Code and open it again, so the skills load.

1. Connect the token the signup gives you:

/one-brain:connect <your-token>

Close and reopen once more, then run /one-brain:status to confirm.

Do the restarts. While the process is alive it keeps using the old copy, and /clear won't help, because that resets the conversation and not the process.

Daily use

Most of the time you do nothing. The team's context arrives when the session starts, and your Claude records what you close.

When you want to be explicit:

• brain_save, or just tell Claude "save this in One Brain"
• brain_search for "what did we decide about X?" or "where is client Y at?"
• /one-brain:handoff to hand off state to your future self or a teammate
• /one-brain:resume to pick up where the last session left off
• /one-brain:doctor when something isn't working

Requirements

You need Claude Code already running, either the terminal or the desktop app. One Brain doesn't replace it. It gives it memory.

It also needs a POSIX environment. macOS and Linux already are one; on Windows, use Git Bash or WSL. jq is optional, since the plugin falls back to python3 and then perl.

Working in Codex instead? There's a Codex build of the same brain.

Your data

One Brain stores what your team decides and learns, not your repository. It doesn't read your source code. Every brain is isolated from every other one, you can see and edit every entry, and you can export the whole thing whenever you want without asking anyone.

More on the security and privacy pages.

Support

bautista@prophet.lat · Built by Prophet

License

Source-available, not open source: see LICENSE. You can read and audit every line before installing it, and run it against the One Brain service. You can't redistribute it or point it at a different service.