Claude Fast has very good alternate documentation for this. [0] I don't understand the hate for defining .claude/ . It is quite easy to have the main agent write the files. Then rather doing one shot coding, instead iterate quickly updating .claude/ I'm at the point where .claude/ makes copies of itself, performs the task, evaluates, and updates itself. I'm not coding code, I'm coding .claude/ which does everything else. This is also a mechanism for testing .claude, agents, and instructions which would be useful for sharing and reuse in an organization.

[0] https://claudefa.st/blog/guide/mechanics/claude-md-mastery