A tool helps you do something you couldn’t otherwise do with a physical aid, such as craft or repair an item, produce multiple chords, or open a lock. You must be trained to use a tool for it to be of value in an activity. Your background, or in some cases, character class will provide the training. Otherwise, similar to learning a language, you must spend time learning to use the tool, working with a mentor/teacher who is an expert.
Tools in this context, take into account expertise as a musician or even mastery of a particular game.
It will take a character 12 months to learn to master an activity using a tool minus 1 month for every point of Intelligence above 12 (minimum of 4 months). During this time, the character must be able to have interactions with a tutor at least three time per week. Delays will be week-for-week. The tutor must be an expert in the use of the tool for the proscribed activity (5+ years of constant use). Basic ability can be achieved much sooner per the GM (ex. gaming etc.).
Tool Set Contents. Work with the GM to determine the specific contents of each set. Obviously, supplies that include ink or paints will include containers for such (pots) as well as paper, canvas or quills. Most kits or supplies can be repacked in a backpack for carrying. Likewise, instruments can be attached to a backpack or wrapped and stored inside. Anything longer than 2½-ft. will need to be strapped on the outside (and most instruments will take the entire volume of a backpack if wrapped).