I assume I should probably document this somewhere, but the launch-related tutorials/guides on docs.ros.org don't really document all the attributes. For example, the args attribute isn't used/mentioned anywhere. Should I just add a section under "New features in this ROS 2 release" for Humble? https://docs.ros.org/en/rolling/Releases/Release-Humble-Hawksbill.html#new-features-in-this-ros-2-release

I assume I should probably document this somewhere

I added it to the launch XML schema (ros2/design#318) and to the list of new features for Humble (ros2/ros2_documentation#1710).

CI --packages-above launch_ros test_launch_ros:

• Linux
• Linux-aarch64
• macOS
• Windows

Is there anywhere ros_args can be added to the documentation? I had to dig to find this issue to understand that ros_args could be used. Is seems there should be documentation added for all launch attributes.

That's a good question. I don't know where this should be documented, especially since in this case the frontends use ros_args while the Node Python class constructor argument is called ros_arguments.

Yes that confused me as well. Ideally they should be named the same across python, xml, and yaml launch files.

I created an issue for this: #404