Use when an agent's output would be a long markdown file that gets skimmed — a spec, implementation plan, design exploration, code or PR review, research report, status update, or slide deck — or a one-off editing/triage/tuning interface, i.e. when tables, diffs, diagrams, color, or interactive controls communicate better than plain text. Not for short answers, trivial edits, or docs that live in version control and are reviewed via diff.
