docs-principles

Checklists for accurate, dense repository documentation - Diátaxis, a density checklist and a compression workflow with before/after metrics. Use when writing, tightening, reviewing or updating a README, docs, ADRs, docstrings or a CLAUDE.md/AGENTS.md, including requests like "make this shorter", "tighten this section" or "this feels bloated" (not for general prose such as emails; how wording steers an LLM - prompts, skills, agents - belongs to prompt-engineering); load it before editing so cuts follow the density checklist and keep rationale and gotchas.