A portable second brain

Own the context.
Rent the models.

Halo is a private brain that lives with you, not inside a chatbot. It remembers your projects, people, and decisions - and every AI you use can read it and grow it.

One brain · every AI

  • Claude
  • ChatGPT
  • Gemini
  • Claude Code
  • Cursor
  • Any MCP client

What it holds

A brain, not a chat log.

Halo stores distilled facts and entities - not transcripts. Every entry has a reference, a category, and a history. This is what a slice of one looks like:

fact:2841decisionShip the beta free - win trust first, charge for hosting later
fact:2842preferencePrefers TDD for anything with business logic
entity:project/haloprojectHalo - own-your-data second brain, hosted beta
fact:2903milestoneDashboard API deployed - 133 tests green
fact:2910provisionalShortlisted for the London Rising Star award - review by Aug 1
fact:2911capturing…

° Provisional facts carry a review date - Halo re-checks what might have changed instead of letting it go stale.

How it works

Three steps. Then it’s automatic.

01

Create your brain

Sign up and a private brain spins up - a store of facts and entities that is yours from byte one. Empty at first. That's the point.

brain created · facts 0 · entities 0 · yours
02

Connect your AI

Paste one URL into Claude or ChatGPT and log in. Two minutes, no code, works on your phone too. The same URL serves every AI you use.

Settings → Connectors → Add custom connector

https://halo-brain.fly.dev/mcp

03

Think as usual

Your AI recalls before it answers and captures decisions, milestones, and preferences as you work. The brain grows itself - you just keep thinking.

“What did we decide about the beta?”

↳ recall → fact:2841 · decision · Ship the beta free - win trust first

Ownership

Yours, verifiably.

Portable

Halo speaks MCP, the open connector standard. The same brain serves Claude today and whatever you use next - switching models no longer costs you your context.

mcp · open standard

Exportable

One click gives you everything as Markdown or JSON. No ransom, no request form, no 30-day wait. Leaving is a feature, not a support ticket.

markdown · json · one click

Private

Your brain is stored encrypted and never read or monetized. When you ask an AI a question, it sees what that question needs - never your whole life by default.

encrypted at rest

Start with an empty brain.
It fills itself.

Free during the beta. Export everything, anytime. Take it to whatever AI comes next.