`Stop` fires for `claude -p`, so the wrap hook re-entered inside the fool's own
generator child. Measured over the fortnight to 2026-09-09: 3 of 10 wrap runs
landed in a generation subprocess, and 18 s of the 80 s of blocking `Stop` —
30% of occasions, 23% of the time — went on occasions that were the end of a
generation nobody was waiting on.
The gate is one predicate against TARBUCKLE_CHILD, which the four seams already
set on the spawn and which `tarbuckle-body.py:203` already reads as a fork-bomb
guard. ⚠ The variable now carries two meanings that do not imply each other —
DO NOT TICK in the body, DO NOT SPEAK OR WORK here — and both sites now say so,
because the next reader would otherwise remove the coupling as arbitrary.
The heartbeat write stays ABOVE the gate, deliberately: it answers "did the hook
fire", and gating it would narrow the one artifact that separates a hook that
never fires from a hook that fires and does nothing.
W6/W6n are BEHAVIOURAL, not source strings — the source-string form of this kind
of check is what passed vacuously for its whole life in the seam (PENDING-180).
Verified by mutation, not by the green run: deleting the gate fails W6 and W6n;
hoisting it above the heartbeat fails the heartbeat arm; nothing else moves.
28/28 controls.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01T1i5VRfHjD79hfaXjWsBXA