This is closely related to  bug 676670 , but more specifically this issue is to add a .md file in //docs, right?

What would be the scope of the doc? Would it be called something like //docs/blink_tools.md and be an overview of third_party/WebKit/Tools/Scripts?

Maybe just a list of each script and what it's used for? Do you think it's worth having this sort of landing page, or if someone is wondering what all the scripts do, would it be better for us to just say "look at the docstrings in each file"?

I'm not sure if it's worth it. More documentation is better, but documentation can also grow out-of-date just like code. Using docstrings with the code is easier.

This reminds me of:
https://chromium.googlesource.com/external/github.com/luci/recipes-py/+/HEAD/doc/user_guide.md#Where_s-the-docs-on

Agreed. Let's shelve this for now.