Better to just have an explicit conversation with the recruiter agreeing to your ethical/personal boundaries. Based on their response you'll probably get a good clue whether or not they respect that.
There are ethical recruiters but as with any group of people you have to sort out the good ones.
(TEKsystems in Southfield, MI, for what it's worth. But this was also 1999-ish.)
I've since found out that it's a pretty common practice and usually the candidates play along just to get the job.
For example, I've had recruiters add in stuff like "2 yrs exp in PHP" when the closest I had gotten to PHP then was editing Wordpress to make it work like it should.
Other time they'd edit my contact info out, change wording, stuff like that. I'm not happy with edits being made without my approval, so I stopped giving them an editable format.
I never saw anything super egregious like lying about skills - but that's not to say it never happened.