Exit codes
Branch on exit codes, not output text.
| Code | Meaning | Commands |
|---|---|---|
| 0 | success / synced | all |
| 2 | URL parse error | storage, copy |
| 3 | no credentials matched | storage, copy |
| 4 | auth failed | storage, copy |
| 5 | store lacks conditional-put (OCC) | storage, copy |
| 6 | destination missing source rows | copy |
copy exit 6 is recoverable: re-run, the union merge converges.