A design reference for the multiplexer's own chrome: a vertical split with a focused agent pane on the left and a stacked-pane fleet on the right, every pane badged with its status. Chrome is ink · paper · one red; program output keeps its own colors.
Tokens · bg #15120f · fg #eae5df · muted #8f8983 · dim #57524b · rule #332f2a · accent #ff563c (focus border, badges, live keys) · dim-accent #a83a28 (needs-input / exited) · borders 1px, single-line · focused pane border = accent, others = rule · corner label = pane name + adapter + status glyph, top-right, dim.