F8 toggles edit mode. Tools: brush/line/rect/ellipse/flood/gradient/picker; ink meanings write LOOK/FLOOR/WALL/WATER/DEPTH across the four screens; V overlays priority/control/hotspot; hotspot rects, prop placement, spawn, and a :colon command line (save/name/enter/music/weather/exit/room/hotmsg). Every editor action is a bus Command (paint_op, undo_op, clear_ops, set_spawn/exit/music/weather/room_name/enter_text, upsert/delete hotspot+prop) so MCP clients wield identical powers. PicOp::Brush added; docs/EDITOR.md. Verified: 5 suites green, playthrough events byte-identical to pre-editor build, GUI boots.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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