Definition
Plain language
A scratch file an AI writes notes in so a future session can pick up where it left off.
As stated in the literature
Agent-authored persistent memory that is the only state carried across context resets; churn rate (similarity between consecutive versions) distinguishes append-only bloat from full rewrites that discard plans.
Also called: notebooks
Why it matters: When conversation history is wiped between sessions, this file is the only thing standing between an agent and starting from scratch every time.
For example, an agent writes "contract expires in June, start talks in March" into a file, and three sessions later reads that line back and acts on it.
Heard on the show
“The analogy that makes this click for me is a research group that operates by passing around lab notebooks instead of Slack histories.”Episode 002 — An AI Ran a Real Optics Lab for 21 Hours and Found a Transformer-Shaped Pattern in Light