CLAUDE.md & AGENTS.md Files: Give Your AI Agent Permanent Memory

This video by Hannah Stulberg (Part 5 of her 'Claude Code for Everything' series) provides a deep dive into CLAUDE.md and AGENTS.md files as persistent memory systems for AI coding agents. The core framework identifies four types of essential context every memory file should contain: document index, people involved, project identity, and workflows/preferences. The video explains a hierarchical folder structure with four levels—personal preferences, company context, area-specific knowledge, and project details—where higher levels should be shorter to optimize the finite 'thinking room' budget.

A critical constraint is highlighted: around 100–150 instructions spread across all CLAUDE.md files combined is the practical limit before instruction-following quality degrades. The video covers three methods for generating files (Plan Mode interview, loading existing docs, and session generation), maintenance strategies, and the @ import syntax for modular context management across projects.