I think there are generally 3 kinds of skills:

1. only information and instructions on how to answer 2. some defined actions (run specific cli commands for specific tasks, use this api with those parameters) 3. skills including scripts

1 seems to be of limited use

2 and 3 can save the agent quite some time for finding a solution. And once the agent found a programmatic solution to a specific problem, they can store this information in a skill