Exit codes

Every code is 0 or 1. There is no third code to branch on.

Command	Exits 0	Exits 1
suss --help, suss --version, suss with no command	Always. Any command given --help prints the usage and exits 0 too.	Never, though an unknown command name prints the usage and exits 1.
suss init	Always. Declining every question, cancelling, and a failed install all end the same way. A failed install prints what npm said and leaves you the command to retry.	Never.
suss extract	It produced at least one summary, or ran with --allow-empty, and neither --gaps strict nor --fail-on-pack-error found something to fail on.	It produced nothing and --allow-empty was not passed; --gaps strict recorded a gap; a pack threw while --fail-on-pack-error was on; an unknown pack, a -p path with no tsconfig, a --dir that does not exist, a bad --lang or --gaps value, a pack config the pack cannot read; or extraction threw.
suss contract	The source loaded, even when it declares no boundary suss could read.	No --from, a source that is not one of the ten, no path, a fetch that failed, or a file suss could not parse.
suss check	Nothing at or above --fail-on (error by default), after suppressions.	Something at or above the threshold; --at matched nothing; a --dir run paired nothing without --allow-empty; --fail-on-unpaired or --fail-on-unreadable fired; or the arguments do not make a form (one positional file, --at with two files, --allow-empty without --dir, --at together with --intent).
suss inspect	It rendered.	The file is missing or is not valid summary JSON; a flag inspect does not take; --changed-files, --budget or --chain without --diff; --diff with fewer than two files; or, given nothing, a project where nothing matched a pack.
inspect --flow	It worked out an answer, including when nothing serves the request.	The request would not parse, there were no summaries to read, or the entry node is ambiguous.
suss ask	The question is one of the ten and its subject is in the summaries it read, even when the answer is empty. Running suss ask with no question prints the list and exits 0.	The question is not one of the ten, nothing in the summaries is at the boundary it asked about, or a why question's chain is not one the run contains.
suss corroborate (experimental)	Every claim that could be tried held up, or nothing was in scope.	A claim was refuted by execution; --experimental was left off; --runs or --attempts was not a positive whole number; or the project has no packs to read with.
infer stub	A draft was written, or printed with -o -.	Nothing in the project refers to the package through a call, an import, a require or a superclass. Also when the target file already exists, or -o points at one path for a Python package that drafts several.
infer intent	At least one doc was written.	No boundary in the summaries could be drafted as intent, or --into points at a folder that already has intent docs.
infer prd	At least one PRD was written.	Every boundary intent already has a scenario pointing at it, a document in the folder is still an uncurated draft, or --into points at a folder that already has PRDs.

When --json is among the arguments, the reason for a usage failure arrives on stdout as {"error": "..."} as well as on stderr, so a caller parsing stdout still gets the reason.

--fail-on-empty is gone from both extract and check. A run that finds or pairs nothing now fails by default; passing the old flag exits 1 and says to use --allow-empty instead.

Suppressions and the check threshold

A .sussignore rule changes what counts toward --fail-on. A finding suppressed with mark or hide does not count; one suppressed with downgrade counts at the downgraded severity. See Accept a finding.