+************
+ Daemon log
+************
+
+The daemon writes short events with the part prefix and ordered
+``key=value`` attributes. An error cause comes last. Normal events use
+info, failures that can be retried or lose nothing use warning, and
+failures that lose data or stop work use error.
+
+With ``JOURNAL_STREAM`` set, each line carries a syslog priority without
+a time stamp or level word. The user journal can show only warnings and
+errors:
+
+.. code:: console
+
+ journalctl --user -u onechat -p warning
+
+The summary warning names its node. A schedule run has ``late`` only
+when it ran late:
+
+.. code:: text
+
+ <4>onechat: summary failed level=0 index=0: fake failure
+ <6>onechat: schedule ran id=1
+ <6>onechat: schedule ran id=2 late=1m0s
+
+Outside the journal, each line starts with the time stamp and level.
+