Struct RegistryEntry 

struct RegistryEntry {
    tracker: Arc<dyn TrackerHandle>,
    last_pids: HashSet<u32>,
    roots: HashSet<u32>,
}

Fields

tracker: Arc<dyn TrackerHandle>

last_pids: HashSet<u32>

Last-known PID set from the most recent poll. Used to diff against the current set so we only emit events for additions/removals — not on every poll tick.

roots: HashSet<u32>

Every PID handed to assign — the agent CLI itself, one per (re)spawn. agent_started excludes them and their non-shell children (MCP servers) from what we report.