Exit codes

Code	Name	Meaning	Raised by	What to do
0	success	Success. Also: the host stopped on Ctrl+C or SIGTERM; a second host found one already running	all	Nothing.
1	failure	The command failed, for example a SQL error, a full disk, or a labelling run that could not reach its API	all	Read the line the command printed. Run it again with LOGBOOK_DEBUG=1 for a stack trace, and run logbook doctor to report it.
2	usage error	Unknown command or option, bad value	all	Check the command and its options against logbook <command> --help.
3	already running	Another command holds a warehouse lock this one needs	sync, forget, compact, labels update, labels run, labels drop	Wait for the other command to finish, or stop it, then run this one again.
4	port in use	The port is in use by another program or another Log Book	start	Pick another port with --port, or stop the program that holds it. If it is another Log Book, open its page instead.
5	unsupported environment	Node older than the floor, or a platform other than macOS and Linux	the shim	Install a supported Node, or run Log Book on macOS or Linux.
6	newer warehouse	The warehouse's schema is newer than this build reads	every command that opens the warehouse	Update Log Book: a newer version wrote this warehouse.
7	missing prerequisite	Claude Code is missing, too old, or not signed in	labels update, labels run, labels plan	Install Claude Code, update it, or sign in to it, as the line says, then run the command again.
8	usage limit	Labelling stopped at your Claude usage limit; every finished batch is kept	labels update, labels run	Run the command again once your Claude usage resets; it carries on from the last stored batch.
9	updated while running	This child's version differs from its host's: Log Book was updated while running	children of a host	Stop Log Book and start it again, so the host and its children run the same version.
10	partial failure	The sync imported what it could, but some step failed or some files were skipped	sync	Read the lines about the failed step or the skipped unit, fix what they name, and sync again.
130	interrupted	Stopped by Ctrl+C or SIGTERM; work already stored stays	one-shot commands	Nothing, unless the command should have finished: run it again.