Exit codes

CLI commands use deterministic exit codes so they compose cleanly in scripts, CI, and agent tool calls.

General contract

Code	Meaning
0	Success
1	Runtime / engine failure (external tool failed, bridge error)
2	User / config error (bad arguments, missing required files, unknown parameters)
3	Quality gate failure (e.g. --min-improvement-nse not met)

swat health

swat health uses its own three-state contract reflecting runtime readiness:

Code	Meaning
0	healthy — engine and reference data resolved
1	degraded — runnable but missing something (e.g. no engine mounted)
2	unhealthy — cannot run

swat health --json && echo "ready" || echo "not ready (see exit code)"

Why deterministic codes matter

An agent or CI job branches on the exit code without parsing prose. A 3 specifically signals a quality gate failure rather than a crash — the run executed, but the result did not clear a threshold. That distinction is the same one the claim governance layer makes in the evidence bundle: it ran and it may be claimed are different facts.