I am talking from a US perspective. At a minimum we must:

1. Guarantee safety for the imprisoned. No more fear of physical / sexual violence. The way people joke about "don't drop the soap" is maddening.

2. No forced labor, no unpaid / barely paid labor. All work must be paid at least prevailing market rates

3. Free of cost essentials - food, clothing, air conditioned shelter, no roommates

4. No price gouging - anything not considered essentials must not cost more than market rate, allow multiple third party vendors in case of disagreement

This is the bare minimum. If we can't meet these, we absolutely must abolish prisons.