Signal only what you started

The coordinator’s rule after the 2026-10-08 incident (BRIEF.md, “Never signal a process you didn’t start”): an engine writer sent SIGTERM to a process group it took for its own, and it was the memory lab’s qualification run.

• Agents never kill, signal or pkill by pattern. They terminate only processes they spawned in this run, identified by pid AND start time.
• One terminator, by full identity. terminate (engine/src/process/process-facts.ts) signals only an OWNED identity: a child this process spawned, read while it is unreaped (ownedChild), a spawn record whose identity carries its start time (readSpawnRecord), or the supervisor’s announcement, bound with the command’s start time read by the supervisor while the child is unreaped (ownedAnnouncement). A null start time NEVER grants ownership (a bare pid can be recycled; round 12, security MF-6). The brand is a WeakSet, so a forged object is refused; the identity is re-checked before each signal, and a recycled group leader is never signalled.
• The lock’s holders follow the same identity rule (INSTRUMENT-LOCK): a holder is live only as this user’s process with its recorded start time.
• The guard. engine/test/prevention/process-liveness-owner.test.ts holds the product and its tooling (engine/src, engine/scripts, server, scripts, bench, shared, src) to the one terminator: a pid-addressed signal there, the default-signal process.kill(pid) included (round 13, K3), is refused outside it. It does NOT read the test roots (engine/test, tests: a test may crash itself or signal a fixture it spawned; K2), and its other known gaps (a systemctl --user stop outside the terminator, process["kill"], a destructured kill, /bin/kill, a spawn record’s trust resting on the privacy of its path) are owned rows (KILL-GUARD-BREADTH, SPAWN-RECORD-TRUST).