Reading command errors

When a command fails, its last stderr line is a JSON error and it exits 1, with nothing on stdout. Logs can come before that line, so capture stderr and read the error with jq:

if ship pane send --pane "$PANE" "Continue" --key enter --wait 2>ship-error.log; then
  echo "Turn finished"
else
  tail -n 1 ship-error.log | jq -r '.message, .caused_by.message'
fi

For a pane blocked on permission, that prints:

nothing was sent
pane pane:0371d3719292450397e5cd5c40295d25 is blocked on permission

For send --wait, the outer message tells you whether the input went out:

• nothing was sent means the command refused before writing.
• the input was sent means you shouldn't send it again, so read the pane or use pane wait.
• the input may have been sent means you should check the pane before you decide whether to retry.

The specific failure is under caused_by. Other command errors also have a category, such as .type.kind being not_found for a missing pane.

A mistyped flag or invalid argument keeps the argument parser's text and exits 2, with no JSON. ship config check is another exception. It prints its findings as text and exits 1 with no extra error line, and a valid config prints nothing and exits 0. --help and --version still exit 0.