Alexandria

Agent Library Systems

A private second brain that lives on your Mac as plain files you own. You feed it — notes, email, a two-minute debrief — and the AI you already run, Claude or ChatGPT, files it into structure and answers from it. No cloud, no accounts.

  • Yours — plain files you own, every change a git commit. Not our servers.
  • Approved — the agent proposes; nothing files, and nothing leaves, without your say-so.
  • Private — it reads your mail, messages and notes on your machine, read-only.
Download Alexandria

v4.7.0 · 1.1 MB · changelog

Works withClaudeandChatGPT

Requirements

  • Apple M2+ with 16GB+ Unified Memory
  • Claude or Codex Pro subscription (to access Claude Code / Codex chat)
  • Access to ~1M+ tokens per day
  • Homebrew and git: Claude Code runs on them (step 1 installs both)

Installation on MacOS 26+

  1. 1Install Homebrew, then git: brew install git
  2. 2Install Claude Desktop (or ChatGPT) and sign in with your Pro subscription
  3. 3Unzip Alexandria-4.7.0.zip into your home folder — not Documents or Desktop (those sync to iCloud, which corrupts a brain)
  4. 4In Claude Desktop, open Claude Code </> and point it at the ~/Alexandria/ folder
  5. 5In the model picker, choose Fable (or Opus 4.8/5) and set thinking to Max
  6. 6Say Install
  7. 7Feed the Library

Or install via Terminal

curl -fsSL https://keystone.computer/install.sh | sh

© Keystone Context Systems, Inc.