Project Brain

project-brain
Different session. Same brain.
A folder structure + collaboration protocol that lets your AI assistant pick up a project after a context wipe — across new sessions, new windows, new collaborators.

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Part of Sprout Labs, Ethan's own product line. Product, design and engineering by one person.
ethanflow.com · LinkedIn · @ethanflow_lab · GitHub

The problem

Long-running projects with AI coding assistants (Claude Code, Cursor, Copilot, etc.) hit a counter-intuitive wall:
Larger context windows don't solve the problem. Better information structure does.

A wider window doesn't mean it gets read. Read doesn't mean located. Located doesn't mean prioritized. Without structure, every new session starts with "wait, what's going on here?" — and the AI either reads too much (wasting tokens) or misses the critical pieces.

Symptoms you'll recognize:

- One README mixing project pitch + current status + decision history + how-to-run
- Sprawling docs where boundaries blur (one architecture file containing design + ops + history + bugs)
- Decisions buried in commit messages, chat logs, and footnotes — never traceable when you need them
- Cross-window handoff loses the "fresh stuff in your head" — the next session starts blind
- Projects running multiple parallel workstreams (e.g., dev + ops + outreach as three parallel streams) lose track of which session is on which line — switching between them re-orients from scratch every time

project-brain is a structural answer: a brain/ folder layout + a small set of protocols, designed so a fresh AI session can read 2-3 files and be productive.

Quick start

Option A — install as a Claude Code plugin (recommended for Claude Code users)

In Claude Code, run these two slash commands:

If /plugin isn't exposed in your Claude…