- drop unused TUI helpers, test-only layout scaffolding, and stale public debug exports
- remove an unused profiler import and trim test-only coverage for deleted helpers
- gateway handler: turnController always archives in recordMessageComplete,
so the post-complete archiveTodosAtTurnEnd().forEach is dead code. Drop
it and the now-unused import.
- turnController: collapse archive prepend into a single spread expression.
- gateway server: one-line comment for the tool.start todo skip.
Two bugs surfaced together while the model fired the todo tool:
1. Count flickered (e.g. 3 → 1 → 3) because tool.start echoed
args.todos as the live state. With merge=true (or any partial
replacement) args.todos is just the items being updated, not the
full list. Drop the early echo — tool.complete already carries the
canonical full list from the tool result.
2. After turn end the panel jumped from under the user prompt to below
thinking/tools because archiveDoneTodos() was pushed AFTER segments
in finalMessages. Prepend the archive trail msg so it sits right
after the user prompt — same visual slot the live panel occupied
during streaming.
- stringWidth: true LRU on cache hit (touch-on-read via delete+set) so
hot strings stay resident under long sessions; was insertion-order
FIFO before
- virtualHeights: include todos, panel sections, and intro version in
messageHeightKey so height-cache reuse correctly invalidates when
todo content / panel sections change
- virtualHeights: estimate trail+todos rows at todos.length+2 (or 2
collapsed) instead of the generic ~1-line fallback, so initial
virtualization offsets are closer to reality
- useInputHandlers: clearTimeout on unmount for scrollIdleTimer so
pending relaxStreaming() never fires after teardown
- render-node-to-output: drop unused declined.noHint counter from
scrollFastPathStats; it was always 0 (the "hint missing" branch is
outside the diagnostics block)
- perfPane / hermes-ink.d.ts: follow the noHint removal
- wheelAccel: replace ~/claude-code path comment with generic
attribution that doesn't reference a developer-local checkout
Adds an `evictInkCaches(level)` API that prunes the four hot module-level
caches (`widthCache`, `wrapCache`, `sliceCache`, `lineWidthCache`) with
either a half-keep LRU pass or a full clear. Wired into:
- memoryMonitor: half-prune on 'high', full drop on 'critical', before
the heap dump / auto-restart path. Gives long sessions a shot at
recovering RSS instead of hard-exiting.
- useSessionLifecycle.resetSession: half-prune so a /new session starts
with a half-warm pool and the prior session can resume cheaply.
Also: lineWidthCache now uses LRU half-eviction on overflow instead of a
full `cache.clear()`, matching the other three caches.
Comparison vs claude-code: both forks now share the same `prevScreen`
blit + dirty-cascade machinery in render-node-to-output. Their smoothness
came from sibling-memo discipline (every chrome pane memo'd so dirty
cascade doesn't disable transcript blit) — already in place in our
appLayout.tsx (TranscriptPane / ComposerPane / StatusRulePane all memo'd).
Alt-screen is not the cause; both use it. The remaining gap was per-row
CPU on width/wrap/slice, which the previous commit closed.
CPU profile (Apr 2026, real-user scroll on 11k-line session) showed three
hot loops in the per-frame render path:
Output.get() per-frame walk: 24% total
└─ sliceAnsi(line, from, to) per write: 18% total
stringWidth(line) chain (cached + JS): 14% total
All three were re-doing identical work every frame: same string → same
clipped slice → same width.
Fixes:
1. Memoize stringWidth (8k-entry LRU) for non-ASCII strings; ASCII fast-path
skips the cache (inline scan beats Map.get for short ASCII, the >90%
case). String.charCodeAt scan up to 64 chars is cheaper than the regex
fallback.
2. Memoize wrapText (4k-entry LRU keyed by maxWidth|wrapType|text) — wrapAnsi
is pure and the same content reflows identically every frame.
3. Memoize sliceAnsi (4k-entry LRU keyed by start|end|str) for the
end-defined hot path used by Output.get().
4. Skip the slice entirely in Output.get() when the line already fits the
clip box (startsBefore=false && endsAfter=false). Most transcript lines
never exceed their container width, and tokenizing them just to slice
(line, 0, width) was pure overhead. This single fast-path drops
sliceAnsi from 18% → ~0% in the profile.
Also tighten virtualization constants (MAX_MOUNTED 260→120, OVERSCAN 40→20,
SLIDE_STEP 25→12) and cap historical-message render at 800 chars / 16
lines via HISTORY_RENDER_MAX_*; messages inside the FULL_RENDER_TAIL_ITEMS
window still render in full so reading-zone behavior is unchanged.
Validation, real-user CPU profile, page-up scroll on 11k-line session:
Output.get() self-time: 24% → 0.3%
sliceAnsi total: 18% → not in top 25
stringWidth family: 14% → ~3%
idle: 60.7% → 77.3%
Frame timings (synthetic page-up profile harness):
dur p95: ~10ms → 4.87ms
dur p99: 25ms+ → 12.80ms
yoga p99: ~20ms → 1.87ms
The remaining CPU in the profile is Yoga layoutNode + React commit,
which is the irreducible work for this UI tree size.
Replaces the static WHEEL_SCROLL_STEP=1 multiplier on wheel events
with an adaptive accel state machine that infers user intent from
inter-event timing.
Algorithm ported straight from claude-code's
src/components/ScrollKeybindingHandler.tsx. All tuning constants,
the native/xterm.js path split, the encoder-bounce detection, the
trackpad-burst signature → all theirs. This file is a mechanical
port into our module structure.
What it does:
precision click (>500ms gap) 1 row/event (deliberate scan)
sustained mouse (40-200ms) 2-6 rows (decay curve)
detected wheel bounce ramps to 15 (sticky wheel-mode)
trackpad flick (5+ <5ms) 1 row/event (burst detect)
direction reversal reset to base
Two implementation paths:
* native terminals (ghostty, iTerm2, Kitty, WezTerm) — linear
window-ramp + optional wheel-mode curve triggered by detected
encoder bounce. SGR proportional reporting handled via the
burst-count guard.
* xterm.js (VS Code / Cursor / browser terminals) — pure
exponential-decay curve with fractional carry. Events arrive
1-per-notch with no pre-amplification, so the curve is more
aggressive.
Selected at construction via isXtermJs() from @hermes/ink (now
exported). Per-user tune via HERMES_TUI_SCROLL_SPEED (alias
CLAUDE_CODE_SCROLL_SPEED for portability).
13 unit tests covering direction flip/bounce/reversal, idle
disengage, trackpad-burst disengage, frac invariants, and the
native vs xterm.js branches.
Profiled under --rate 30 (stress test) and --rate 10 (realistic
sustained scroll): accel ramps to cap=6 at 30Hz burst, decays to
1-3 rows at sparse 10Hz clicks. Perf is comparable to baseline
because accel IS multiplying step — the win is perceptual (fast
flicks cover distance, slow clicks keep precision), not raw fps.
Companion to the earlier WHEEL_SCROLL_STEP=1 change: that set the
base; this modulates around it.
User observation: "it doesn't scroll line by line/row by row."
Was right. Two places hardcoded big deltas:
1. WHEEL_SCROLL_STEP = 6 (config/limits.ts)
Each wheel event scrolled 6 rows. A mechanical wheel notch emits
3-5 events → 18-30 rows per click, which visually teleports past
content instead of smooth-scrolling it. Drop to 1. Trackpads
emit 50-100 events per flick — at step=1 that's still a fast flick
(a whole viewport in one flick) but each intermediate frame is
visible. Porting claude-code's wheel accel state machine is the
right next step if this feels sluggish on precision scrolls.
2. pageUp/pageDown = viewport - 2 (useInputHandlers.ts)
Full-viewport jumps replace the entire screen — no visual
continuity, can't scan content — AND land right at Ink's fast-path
threshold (`delta < innerHeight`), which disqualifies the DECSTBM
blit on every press. Half-viewport keeps 50% continuity AND
drops well under the threshold. Two presses still cover the same
total distance.
Profiled against the 1106-msg session, holding the key at 30Hz for
6s:
wheel_up (step 6 → 1):
frames 142 → 163 (+15%)
throughput 10.7 → 15.8 fps (+48%)
patches tot 53018→ 36562 (-31%)
gap p50 5ms → 16ms (actual rendering ~60fps now)
<16ms frames 93 → 76
16-33ms 82 → 76
hitches 3 → 1
pageUp (viewport-2 → viewport/2):
throughput 10.7 → 9.5 fps (same ballpark — smaller delta × same
event rate = less total scroll)
Ink's proportional drain caps at `innerHeight - 1` per frame to keep
the DECSTBM fast path firing. With these smaller deltas every event
comfortably fits under that cap, so fast-path hit rate goes up and
patch volume per frame drops — the measured 31% reduction in total
patches-sent correlates with users perceiving smoother scrolling
because the outer terminal (VS Code / xterm.js / tmux) isn't drowning
in ANSI between paints.
Tests/type-check/build clean; 352 tests pass.
The ephemeral no-tools side-question variant of /btw confused users who
expected 'by-the-way' to mean 'run this off to the side with tools' —
they'd type /btw and get a toolless agent that couldn't do the work.
/bg worked because it was /background with full tools.
Collapse the two: /btw and /bg both alias to /background. One command,
one behavior, no more gotchas about which variant has tools.
Removed:
- _handle_btw_command in cli.py and gateway/run.py
- _run_btw_task + _active_btw_tasks state in gateway/run.py
- prompt.btw JSON-RPC method + btw.complete event in tui_gateway
- BtwStartResponse type + btw.complete case in ui-tui
- Standalone /btw slash tree registration in Discord
- Standalone btw CommandDef in hermes_cli/commands.py
Updated:
- background CommandDef aliases: (bg,) -> (bg, btw)
- TUI session.ts: local btw handler merged into background
- Docs and tips updated to describe /btw as a /background alias
PR #16046 added /busy and /verbose hints to the classic CLI and the
gateway runner but skipped the Ink TUI (and therefore the dashboard
/chat page, which embeds the TUI via PTY). This extends the same
latch to the TUI with TUI-native wording.
The TUI's busy-input model is not the /busy knob from the CLI —
single Enter while busy auto-queues, double Enter on an empty line
interrupts. The new busy-input hint teaches THAT gesture instead of
telling the user to flip a config that does not apply.
Changes:
- agent/onboarding.py — add busy_input_hint_tui() + tool_progress_hint_tui()
- tui_gateway/server.py — onboarding.claim JSON-RPC (Ink triggers busy
hint on enqueue) + _maybe_emit_onboarding_hint helper hooked into
_on_tool_complete for the 30s/tool_progress=all path. Same
config.yaml latch so each hint fires at most once per install across
CLI, gateway, and TUI combined.
- ui-tui/src/gatewayTypes.ts — OnboardingClaimResponse + onboarding.hint event
- ui-tui/src/app/createGatewayEventHandler.ts — render the hint event as sys()
- ui-tui/src/app/useSubmission.ts — claim busy_input_prompt on first
busy enqueue
- tests/agent/test_onboarding.py — +3 cases for TUI hint shape
- tests/tui_gateway/test_protocol.py — +4 cases for onboarding.claim
- website/docs/user-guide/tui.md — new 'Interrupting and queueing'
section explaining the TUI's double-Enter model and the hints
Validation:
scripts/run_tests.sh tests/agent/test_onboarding.py \
tests/tui_gateway/test_protocol.py \
tests/gateway/test_busy_session_ack.py
-> 66 passed
npm --prefix ui-tui run type-check -> clean
npm --prefix ui-tui run lint -> clean
npm --prefix ui-tui run build -> clean
Follow-up on #16020 salvage. Three corrections:
1. Truth signal for /copy
Before: success was 'OSC 52 sequence was emitted to stdout'. That's
false on local Linux inside tmux (emitSequence=false), so /copy kept
printing 'clipboard copy failed' to users whose xclip/wl-copy had
already succeeded fire-and-forget.
Fix: setClipboard() now returns { sequence, success } where success =
native-fired OR tmux-buffer-loaded OR osc52-emitted. copyNative()
returns a boolean telling setClipboard whether a native attempt was
made. /copy only shows 'failed' when literally no path was taken.
2. Dashboard keybinding
Before: Ctrl+C for copy on non-Mac (Ctrl+Shift+C for paste).
That swallows SIGINT when a stale selection is present and breaks
the xterm/gnome-terminal/konsole/Windows-Terminal convention where
Ctrl+C in a terminal emulator is always SIGINT. The real bug was
that clipboard writes lost user-gesture through OSC-52 round-trips,
which the direct writeText already fixes.
Fix: revert copyModifier to Ctrl+Shift+C on non-Mac. Direct
writeText in the keydown handler preserves user gesture. term.write
Escape replaced with term.clearSelection() (works without relying
on TUI input mode).
3. Error toast text
Before: 'see HERMES_TUI_DEBUG_CLIPBOARD' — tells users how to
debug but not how to fix.
Fix: point users at HERMES_TUI_FORCE_OSC52=1 first (the actual
escape hatch), mention the debug var second.
- Dashboard copy: direct Clipboard API on Ctrl+C/Cmd+C (user gesture);
send Escape to TUI to clear selection; Ctrl+Shift+C kept as fallback.
- TUI /copy: copySelection() async; only reports success if OSC52 emitted.
- Add HERMES_TUI_FORCE_OSC52 env var to override native-tool detection.
- Fixes "copied N chars" false-positive when clipboard backend absent.
Changes:
web/src/pages/ChatPage.tsx — direct navigator.clipboard.writeText
ui-tui/packages/hermes-ink/src/ink/ink.tsx — async copySelection
ui-tui/packages/hermes-ink/src/ink/termio/osc.ts — HERMES_TUI_FORCE_OSC52
ui-tui/src/app/slash/commands/core.ts — async /copy with honest feedback