Edits must be at least 6 characters;
That simply is there to prevent excessive editing sprees. Keep in mind that after the 10th edit of a question (by all users who edited a question), the question automatically turns into a community wiki. And when that happens, you loose all reputation points (and possible privileges that go along with it) from that question.
[...] is there something else to improve in this post?
There always is something that you can add to a question :)
Link to sources or reference material for example. Or explain what an API function really does. Just adding markup doesn't really add value. It's easier to read, but it doesn't necessarily help understanding what you tried to explain.
Last note: In case you were talking about this answer (I know you didn't, but it jumped at me), then please: Take a look at the WYSIWG editor buttons. There's a button for
code formatting. Do not format code as bold, but format it as it is: Code.
There're also buttons for lists, etc. On the upper right side of the editor window, you will find a small yellow
(?) question mark in a circle. It points to the editing help page. Please take a look at this page.
Hope that helped :)