Exit codes

Code	Meaning
0	Done. With --exit-code, also: the deployment matches the lane file
1	An error, or with plan --exit-code, problems that block apply
2	The command line was refused (an unknown flag, a missing argument)
3	plan --exit-code or status --exit-code: the deployment differs from the lane file
4	caravel wait: the time ran out

caravel plan --exit-code --env testnet        # in CI: 0 means nothing to apply

Every command takes --json: JSON on stdout, progress and notes on stderr.