I asked my coding agents a simple question: how much did you actually read while we built this project?

The answer: about 1.2 billion tokens , across 32 work sessions in Claude Code and Codex.

A token is roughly ¾ of a word, so that's around 900 million words. About 10,000 novels. For one side project.

The part that bothered me wasn't the size. It was that most of it wasn't new . It was the same conversation being re-read turn after turn. The same test output. The same files. The same "so, how do you run the tests here?" that I had already answered on Friday.

So I built simem . It's free, MIT-licensed, and runs entirely on your machine. This post walks through the three problems it solves, with screenshots and numbers instead of vibes.

TL;DR

Every new session starts from scratch. simem gives the agent a short summary of your project before you type anything.

Memory is stuck in one app, one account, one folder.…