That confused me as well. The whole point of CLAUDE.md is that it is automatically injected into the rolling context of any Claude interaction/thread.

That CLAUDE.md file that they've posted is also HUGE - Anthropic themselves recommend keeping it on the more concise side. If you need more, consider just creating dedicated subagents for "UI/UX reviewer", "search", etc.

My CLAUDE.md has references to other documentation

Like "for guidance on Go library selection refer to docs/go.md"

That way the main file stays compact.

subagents were not yet released at the time of my blog post