To see your description, type desc. To edit it, type desc edit. Use the following as an example:
desc edit
Entering the text editor, type .h for a list of commands.
Current text:
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An elven girl just entering her teens. She's been doing that for
so long that she's forgotten how to get out of them. But she's very
much an expert 13-year-old.
.e
Done.

While you are in the text editor, you can type .h to get the editing commands. Those should be easy enough to follow. They're listed on the