While HELP is indeed informative it is missing some commands that are used in Pico-8. I'm not going to mark these as errors, @zep, as they may just be overlooked. This includes:

goto count setmetatable getmetatable rawset rawget rawequal rawlen assert . Likely there are others.

While not required for help it would be nice if there was HELP for these single-key shortcuts:

? # @ % $ \

If you ask for help on do it does not give a code example which is odd as all the other commands do.

Further the HELP could also appear if you are one-character to the right of the command.

pset(4,8)

Where the cursor is on the ( Pressing CTRL+U does not give help on it.

Should also work if the cursor is directly on the ) which is linked to that same command.