About the artist description in their art

Where should I put the artists description of their work?

Like in the post #6673940 and post #6673945 the artist have a description of their work on the Twitter/X.

You mean the ALT text? I usually see people put that in the commentary field, since it doesn't really fit anywhere else. Two examples: post #6314015 post #6286919

Oh, ok, I'll do what they did in the post you given, thanks.