In my experience, I have not found any platform's provided skills worthy of inclusion. The number one reason is that they are often huge and cover the entire surface, or there are a bajillion of them. That these are presented as such shows they lack understanding about how to context engineer and have no respect for our token bills. Most seem Ai generated and come with the hallucinations and all that.

Have you vetted your skills for accuracy and conciseness?

Regarding harness level skill usage, that should be relatively easy for the user, as their harness should have saved the complete history of all sessions.