Gateway看门狗-知微 was erroring (exit -15): its check_session_health did a
live LLM ping with 25s timeout. Cold-start LLM latency is 20-100s so the
ping always timed out -> false '不健康' verdict -> false gateway restart
-> and each 10-min run burned 22k tokens.
Now uses xmpp_logger._scan_agent_log (zero cost, reads real call results):
- ok if last real call succeeded
- unhealthy only if last call explicitly failed
- idle (no recent calls) counts as healthy
Verified: watchdog job now status=ok.
Also: triggered all 6 weekend 'Blocked' jobs via hermes cron run — all
now status=ok, proving the hardlink fix holds.