Cross-plugin accessor for "does agent have on_call slot covering this
window?" — first consumer is Dialectic.OpenclawPlugin signup pre-check
(its hf-precheck.ts has been degrading to "skipped" since Phase 3
ship pending this).
v1 honest scope: same-day windows only (scheduleCache is today-only
from /calendar/sync). Cross-day or empty-cache windows return undefined
which the caller treats as "skipped" (Dialectic backend stores
pre_validated:false as audit signal — same as before, just now we
actually validate when we can).
Logic: for each cached slot where slot_type=on_call AND status not in
{aborted,cancelled}, parse scheduled_at (HH:MM:SS or full ISO) and
estimated_duration to compute end; return true iff start<=from AND
end>=to. Returns false (not undefined) when cache has slots for the
agent on this date but none covers — that means "actually no coverage"
vs "I dont know".
Pairs with Dialectic.OpenclawPlugin/src/hf-precheck.ts which already
calls hf.hasOnCallCovering and handles all 3 return shapes.
No backend change required.
hzhang
c2d00c18a7