Provides expert guidance for writing compact, effective technical documentation. Use this skill when: (1) user mentions "documentation", "docs", "document", "readme", "architecture", or "API docs", (2) user requests to write, create, update, improve, or review any documentation, (3) user is documenting code, systems, features, or APIs, (4) user is creating README.md, ARCHITECTURE.md, CONTRIBUTING.md, or tutorial files, (5) user requests examples or how-to guides.