I've tried to add tag-wikis in the last few days, but I'm running of tag-wikis in areas which I know good enough :-(

I've also been adding tag-wikis at meta, mostly copying them from meta.SO. (I think it my be useful if the tag-wiki and tag-excerpt give some guidance, especially when it is not clear which tags should be used.)

I've suggested tag-excerpt for close-reasons by copying the text from the meta.SO tag-wiki, which contains the text: For instructions and guidance on closing or migrating questions, and the reasons for those closures. I am not sure this is correct - since we have separate tag for migration.

is it unacceptable to copy excerpts from wiki articles to use for tag wikis?

I believe it is perfectly acceptable.

so we could just to that then

See this post at meta.SO: What to do about large amounts of plagiarizing in tag wikis?

The question was: i've recently noticed, by one user in particular, a rash of tag wiki updates where the text is copied verbatim from either Wikipedia, documentation or another website. ....

The answer can be summarized as: If the content is good, then who cares?

Also this post at meta.SO: Would it be OK to paste content from Wikipedia into a popular empty tag-wiki?

@Eugene Yes, but I still feel more comfortable with writing a tag-wiki to a tag which I know something about or which I have followed for some time (or created).

In particular, sometimes there is problem that the name of the tag has several meanings.

And of course there are other problematic tags like proof-strategy and similar tags, where I am not entirely sure what is the intended usage. So in that case I am not able to write a tag-wiki and tag-excerpt.

@MartinSleziak how useful do you think that tag is?

one of its unique coverage i think would be if a poster only wanted a hint and not a full answer

but that's not really all that useful since the poster can just ask for that

It seems that there was some discussion at meta.

Perhaps this question and the linked questions might be interesting in relation to this: Tags (proof-strategy) and (proof-writing).

But I've written this merely as an example of a tag, where I am not sure about it's precise purpose - we have more such tags.

@MartinSleziak the inception is really weird. i would have tagged it real analysis

But in my opinion proof-strategy makes sense. In the same sense I consider tricki.org very useful and interesting. But I would not be able to suggest some clear guideline about what belongs into the tag.

@MartinSleziak i don't know if it does. but i guess that's just my opinion

@MartinSleziak I've pinged Zev Chonoles (one of the mods) about this. He added this sentence to the tag-wiki: When a question is migrated away from one Stack Exchange site to another, the original copy of the question is closed, which is why migration falls under the heading of closure.

This is IMO a very satisfactory explanation why migration was mentioned there.

i agree