Descriptions:
This short official video from Anthropic’s Claude channel explains the CLAUDE.md file — the mechanism Claude Code uses to maintain persistent context about a project across sessions. Without a CLAUDE.md in the project root, Claude Code starts fresh each time: re-exploring the codebase, re-inferring dependencies, and making assumptions about conventions. The CLAUDE.md file is appended to every session prompt automatically, functioning as a standing system prompt for the codebase.
The video walks through a concrete example for a Next.js 15 app using App Router, Tailwind CSS, and Drizzle ORM, showing how the file captures the dev server command, test and lint commands, code style preferences (two-space indentation, named exports), and routing conventions (server actions over API routes where possible). It also introduces the memory hierarchy: a project-level CLAUDE.md committed to version control for the whole team, and a user-level CLAUDE.md stored in the config folder for personal preferences that apply across all projects.
Practical guidance includes using the /init command to generate a first draft from the existing codebase, starting new projects without a CLAUDE.md to identify only the corrections that actually matter, and keeping the file lean by adding entries only when Claude needs repeated correction. The video is a concise official reference for developers setting up Claude Code on a new project or trying to reduce prompt drift across sessions.
📺 Source: Claude · Published May 10, 2026
🏷️ Format: Tutorial Demo
