All the documentation is inserted in caml files as comments. You'll need to tag your comments in order cdk_doc to understand them. A comment is tagged if you start it with some predefined char.
Documentation comments must start at the beginning of a new line. Other comments are printed as comments at the end of code lines.
Here are the different beginning of comments understood by cdk_doc:
If a comment contains the string "$id", all following untagged comments are treated as if starting by "(*d", for compatibility with former .mli files.
In all your comments, if you write something inside "[]", it will be displayed as inline code. If you write something inside "{{" ... "}}", it will be printed as preformated code. Normal "[]" should be written with backslashes.
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