Two-layer prod-safe gate for the acpToolSummaries experiment, default OFF:
UI gate: buildCompactToolSummary now takes summaryTitleEnabled (default
off) and only consults the agent-provided friendly phrase when the
experiment is on. ToolItem and BotActivityBar/getActivityHeadline read
useFeatureEnabled('acpToolSummaries') and thread the flag through.
Failure-precedence behavior is unchanged: failed rows always paint the
failure label regardless of the gate.
Runtime/cost gate: the frontend mirrors preview-experiment overrides to
experiments.json via the new set_desktop_experiments command (AppShell
mirrors on boot and on every toggle); spawn_agent_child sets
BUZZ_AGENT_NO_TOOL_SUMMARY=1 when the experiment is off so disabled
agents never spend the async LLM summary call. All spawn paths (start,
create, app-startup restore) funnel through spawn_agent_child, and
missing/unknown mirror state resolves to off — restore-time respawns
before the webview loads stay on the safe side. Experiment-on leaves
the env untouched, so a user-provided kill switch still wins.
Co-authored-by: Taylor Ho <taylorkmho@gmail.com>
Signed-off-by: Taylor Ho <taylorkmho@gmail.com>
