Inspector: size to the terminal, page it, and a full-screen view

[navbytes]

Reported from real use: the inspector's right pane truncates, and there was no way to see the rest.

The caps were hardcoded and ignored the terminal —

block("Payload", JSON.stringify(st?.input ?? {}, null, 1), 8)
block("Result",  String(st?.output ?? ""),                10)
block("Text",    part?.text ?? row.preview,               14)

— so a tall window sat half empty under a dead … 61 more lines (y to copy), and the pane was a flat <For each={inspectorLines()}> with no scroll state at all.

Three changes, in the order they matter

1. The window is sized from the terminal. Every line is materialised (bounded by INSPECTOR_MAX_LINES only so a pathological payload cannot build an unbounded array per render) and the window comes from height(). A taller terminal simply shows more, with no new keys — this alone fixes the common case of a 30-line payload cut at 10 while the pane has room.

2. PgUp / PgDn page it, with no focus mode. j/k must keep driving the row selection, because that is what chooses the inspector's content; a "focus the pane" concept would add modality to a route that has none, and Tab is already fold/unfold. PgUp/PgDn were unbound, need no focus, and already mean "scroll a pane". The dead notice becomes a live position:

┃            "status": "completed"
┃ 12–40 of 118 · PgUp/PgDn · y copy · I full

The offset resets when the selected row changes — new content, new top.

3. shift+i opens it full screen (and from a closed inspector, opens it there directly), esc returns it to the side pane. A ~40-column pane is not a JSON viewer, so this is the "show me all of it" answer.

Bug fixed

showInspector() required cols() >= 110 with no fallback and no message, so on an 80-column terminal i flipped a flag that rendered nothing and said nothing — the inspector was simply dead. It now opens full screen there, which is both the fix and the pi-context-tree inspect view DESIGN.md §7.1 has promised since 0.1 and never shipped.

Where the logic lives

The scroll arithmetic went into core/navigation.ts#paneWindow / scrollPane rather than the route, because this is exactly where off-by-ones hide silently. Clamping is in the getter, not the setter, so a resize or a shorter row cannot strand the view past the end of the new content.

9 new tests: the last page sitting flush with the end rather than scrolling into blank space, symmetric up/down with both clamping, the two-line page overlap, paging down repeatedly landing on the last page and stopping, empty content reading 0 instead of 1–0 of 0, a one-line pane still advancing, and a deep offset surviving a switch to much shorter content.

What I deliberately did not do

Make this feel like a JSON viewer. y remains the answer for actually reading a large payload — somewhere with search and folding — and the pane footer keeps saying so. The scroller is for "there were twelve more lines and I want to glance at them"; full screen is for "show me the shape of this".

Tests

252 pass, 0 fail. Typecheck and build clean.

Not verified here: the e2e suite — opencode serve does not bind in this container (reproduced with no plugin installed at all). This is TUI-render and keybinding work covered by unit tests for the arithmetic, but the /tree e2e drives the real TUI and should cover it before release.

🤖 Generated with Claude Code

https://claude.ai/code/session_01BrwAnTfTmJSmFwVn3DDFxr

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Generated by Claude Code