About exit codes

GitHub uses the exit code to set the action's check run status, which can be success or failure.

Exit status	Check run status	Description
0	success	The action completed successfully and other tasks that depend on it can begin.
Nonzero value (any integer but 0)	failure	Any other exit code indicates the action failed. When an action fails, all concurrent actions are canceled and future actions are skipped. The check run and check suite both get a failure status.

Setting a failure exit code in a JavaScript action

If you are creating a JavaScript action, you can use the actions toolkit @actions/core package to log a message and set a failure exit code. For example:

try {
  // something
} catch (error) {
  core.setFailed(error.message);
}

For more information, see Creating a JavaScript action.

Setting a failure exit code in a Docker container action

If you are creating a Docker container action, you can set a failure exit code in your entrypoint.sh script. For example:

if <condition> ; then
  echo "Game over!"
  exit 1
fi

For more information, see Creating a Docker container action.