IO diagnostics — round 2 brief (Zach's feedback, 2026-10-22 14:46, Daily Note "Feedback on thing")

What he said (paraphrased; his screenshots: a private note, …144719.png, …145139.png)

Grouping on the computer is cool, but the physical layers (host, USB bus, port, tty, CAN bus, driver/motor parts) obscure the actual entities. His mental model: fdcanusb → Moteus c1 · CAN 15, Moteus c1 · CAN 12.
Single computer = an unnecessary fold (VS Code: the workspace root only appears once there are several top-level folders; with one you are "within" it). Elide rack-pc when there is one host.
Tree style: between Quiet IDE (v1) and Notion (v2). Quiet IDE's benefit: you see at a glance which rows are folders (can expand). The table view must match the tree (same structure, same row grammar).
"How do we reconcile the USB data and the simpler data? Maybe a toggle to show USB/PCIe ports?" → 5 proposals for entities at a glance + detail when you want it.
The table (aligned columns) is the shape he likes — without the extra structural rows.
11 skins, each with light and dark: 1 Claude, 2 Obsidian, 3 Notion, 4 Terminal, 5 Foxglove/medkit, 6 stock shadcn/ui, 7 Unstyled (bring your own tokens), 8–11 orchestrator's picks, orthogonal. Users may pick a skin, but there must be a great default.
His goal today: "I plug it in and now I need it to run — such a basic thing."

Decisions (orchestrator)

Rows are entities, labelled model · id (e.g. Moteus c1 · CAN 15, RealSense D405 · 4411, fdcanusb · XXXXXXXX). Composition parts (driver, motor) are not rows by default: their status surfaces on the owner row ("driver: fault 33"), the parts are listed in the detail panel. The black-box rule is unchanged (own report shown, worst-below as a hint).
Single-host elision in every proposal: one host → its children are the top level; several hosts → host rows appear.
Tree styles: keep v1 (Quiet IDE) and v2 (Notion); add v6 "IDE × Notion": chevrons always visible but quiet on expandable rows (you see the folders), Notion's restraint (no guides, hover-revealed affordances). v3–v5 stay available but are no longer the focus.
Default skin = 1 Claude (variant 1 applied as default); light/dark follows the OS (prefers-color-scheme) with a manual toggle; all choices persist (localStorage, try/catch) and switch live from the bottom-right control.

The 5 structure proposals (entities at a glance, transport on demand)

P1 Devices, transport as columns — only entities in the tree; the physical path becomes quiet columns/badges (USB 1-3 · 12 Mb/s · ttyACM0, PCIe 0000:01:00.0 x1/x4). Table-native.
P2 Two views, one toggle — "Devices" (by function: Actuators · Cameras · Buses · Computer) ↔ "Connections" (the physical USB/PCIe/net tree). Precedents: Windows Device Manager "Devices by type / by connection", ros2_medkit Logical / Functional.
P3 Path on demand — entity tree; the connection path appears as a muted breadcrumb under the hovered/selected row and in full in the detail panel (USB bus 1 › Port 1-3 › ttyACM0).
P4 Compact folders — the physical tree, but pass-through nodes auto-fold: single-child chains join into one row (VS Code explorer.compactFolders), empty buses/ports hide behind "show empty", tty nodes become attributes.
P5 Bus lens — top level = the communication buses the robot cares about (CAN XXXXXXXX, CAN XXXXXXXX, the USB cameras, PCIe capture), each listing its nodes; the computer's internal topology collapses into one "Computer" row that expands to the physical tree.

The 11 skins (CSS tokens only — every skin works with every structure and tree style)

1 Claude (warm neutrals, serif display, generous spacing) · 2 Obsidian (dark-first purple accent, compact) · 3 Notion (black-on-white restraint, emoji-free iconography) · 4 Terminal (monospace, ANSI palette, box-drawing) · 5 Foxglove / ros2_medkit (dense robotics tooling, cool greys) · 6 stock shadcn/ui (zinc, default radius) · 7 Unstyled (structure + semantic tokens only; a documented token sheet to bring your own) · 8 ISA-101 high-performance HMI (industrial: grey everywhere, colour only for abnormal — the standard behind "quiet when OK") · 9 macOS System Settings (native Apple HIG) · 10 Linear (precise, dense, keyboard-first) · 11 High contrast / WCAG AAA (accessibility, also prints well). Gates for every skin in both modes: quiet-when-OK holds (no colour on OK rows), WCAG AA contrast for text and status shapes (measured), problem shapes stay distinguishable without colour.

Shared seams (frozen once the foundation lands)

web/view/core.js: API state → display rows; IOStructures[id] = {name, rows(state, options)}; options include showTransport, showEmpty, query.
web/tokens.css: the semantic token list (--io-bg, --io-surface, --io-text, --io-muted, --io-border, --io-accent, --io-warn, --io-error, --io-stale, --io-unknown, --io-font-ui, --io-font-mono, --io-radius, --io-row-h, --io-focus, …); skins live in web/skins/<id>.css as [data-skin=id][data-mode=light|dark] { … }.
Tree renderers and the table consume rows from the active structure, never the raw API tree.