diff --git a/docs/re/mission-freeze-resume-spin.md b/docs/re/mission-freeze-resume-spin.md
index c3ed128..8e1399e 100644
--- a/docs/re/mission-freeze-resume-spin.md
+++ b/docs/re/mission-freeze-resume-spin.md
@@ -583,3 +583,52 @@ in here attributes a SIGKILL to its sender (no `dmesg`, no audit, and
 `ptrace_scope=1` limits `strace` to my own descendants). The practical response
 is to stop designing experiments that need a *long* run: the counter transitions
 the OB work needs all happen in the first minutes of flight.
+
+
+---
+
+# ✅ 2026-08-24 — THE KILL IS SOLVED, and it was never the game: a Stop hook
+
+**Everything above about the `EMULATOR GONE` / SIGKILL failure mode has a
+one-line cause**, and it is not in the emulator, the container runtime or the
+kernel. It is in this project's own Claude Code configuration —
+`/work/.claude/settings.json`:
+
+```json
+"Stop": [{ "hooks": [{ "type": "command", "command":
+  "for name in xenia_canary xenia-rs; do pids=$(pgrep -x \"$name\"); ...
+   kill $pids; sleep 0.2; kill -9 $pids; ... 'Stop hook killed %d stale xenia process(es)'"
+}]}]
+```
+
+A `Stop` hook fires at the **end of every agent turn** and `kill -9`s any running
+`xenia_canary`. So every run that "died mysteriously" died at a turn boundary,
+which is exactly why the timings looked random from inside the run (810 s, 54 s,
+486 s) and why nothing in the guest, the cgroup or the host explained them.
+
+**What survives from the investigation** is only the measurement, not the story:
+the memory readings were real and did refute memory pressure as a cause — the
+cgroup was at 6.5 GB of 7.0 and the host had 12 GB free at the moment of a kill.
+That refutation was correct; it just was not pointing at anything.
+
+## 🔑 The method lesson, which is the part worth keeping
+
+**When a process dies at a session boundary, check the harness before
+instrumenting the guest.** Three iterations went into this: a failure mode
+documented, a memory hypothesis raised, a per-poll memory sampler written and
+committed, host and cgroup counters read — all of it downstream of an assumption
+that the kill came from *outside the agent*. The one place not looked at was the
+agent's own configuration, and that is where it was. The `systemMessage` the hook
+prints ("Stop hook killed 1 stale xenia process(es)") is surfaced to the user
+after each turn, so the answer had been on screen the whole time.
+
+## The rule that follows
+
+**An emulator experiment must complete inside a single turn.** Nothing survives
+the turn boundary, so:
+
+* do not "leave a run going for the next tick" — it will be killed;
+* prefer experiments whose evidence arrives in the first minutes of flight (the
+  `REMAINING OB` transitions all do — that is why the two-pass bit-level test
+  succeeded where the long freeze-watches did not);
+* a watcher armed for 1 500 s can only ever watch for the rest of *this* turn.