A service running as the operator — the tool runner, a unit of the account's user manager — shares the operator's user id, and was as much the terminal on the control-node as a person typing. The engine now reads the asking process's cgroup and sends its login session's scope (session-<id>.scope under the account's own user-<uid>.slice), or nothing; the controller makes nothing else the terminal. The SDK is pinned at its tag now that go/v0.1.9 exists.