docs(agents): default cron jobs to automation agent

AGENTS.md

@@ -228,6 +228,10 @@ You are free to edit `HEARTBEAT.md` with a short checklist or reminders. Keep it
 
 ### Heartbeat vs Cron: When to Use Each
 
+**Cron agent default:**
+- In direct sessions with Will, use the `automation` agent for cron jobs by default.
+- Only use a different agent if Will explicitly instructs otherwise in that session.
+
 **Use heartbeat when:**
 
 - Multiple checks can batch together (inbox + calendar + notifications in one turn)

MEMORY.md

@@ -32,6 +32,7 @@
 - Treat Telegram DMs and TUI/webchat as separate main-session contexts when `session.dmScope = "per-channel-peer"` is active.
 - Use local-first search by default: SearXNG first, then Brave-backed fallback when needed.
 - Brave free-plan search is rate-limited heavily; avoid parallel bursts.
+- In direct sessions with Will, cron jobs should use the `automation` agent by default unless Will explicitly says otherwise in that session.
 
 ## Infrastructure notes worth remembering
 - Full `~/.openclaw` backups upload to MinIO bucket `zap` and are scheduled via OS cron every 6 hours.