Your AI Coding Agent Is Brilliant and Amnesiac. One File Fixes That.

I opened a new Claude Code session and asked it to add a feature to a tool I'd been building for three weeks. It asked me what language the project was in. Three weeks. Dozens of sessions. Hundreds of decisions. And the AI started from zero — as if we'd never met. That's not a bug. That's how every AI coding agent works. Claude Code, Cursor, Windsurf, Copilot — every session is a blank slate. The agent can write complex systems in minutes, but it can't remember what you named the database table yesterday. Most people solve this by re-explaining. They paste context into the first message. They describe the project. They remind the AI about conventions. Every single session. Then they wonder why they're burning through their Max plan 5x allowance in two hours. Every re-explanation is tokens. Every clarifying question the AI asks because it doesn't know your stack — tokens. Every time it suggests a migration you already rejected — tokens, plus the tokens you spend correcting it. You're no