A few years ago I was a project leader. Someone who worked on that project often uses me as a reference, even though neither of us are on that project or with that employer any more. This person was excellent technically. Unfortunately, the person lacked social skills and shunned most social interactions. From the number of reference requests I receive, I know the person has had some difficulty finding and keeping employment and suspect their problems with social interactions are the cause.
Whenever a reference request for this person comes to me, I always try to stress the person's technical skills. With some reference requests, this is all that is asked. However, some potential employers want to know about the person's social skills, having observed related issues in an interview. For these, I usually try to say something about how the person is socially awkward, but a good person. This never feels quite right.
How can I provide a truthful reference that minimizes or even eliminates the issues with the person's social skills?