Professional Reference

Someone that I've worked with for a few years has applied for a job as an adjunct in the Math/Science Department of Southern Urban Branch Campus Community College.

I know this because I just got an email from the adjunct coordinator in the Math/Science department of SUBCCC asking specific and pointed questions about my colleague. Apparently my colleague listed me as a reference.

So the question is how honest should I be? I want to give the hiring coordinator enough information to make a good decision, but I'm not sure how useful my candid information would be if the coordinator is comparing my colleague to other candidates whose references are hyperbolic in their praise.

And I wouldn't really mind if this colleague got a job elsewhere.