Some are and some aren't.
It used to be that ALL Craftsman tools came with a real lifetime warranty. (Not the kind of waranty that defines the lifespan of a hammer as 5 years, and the warranty is good for that 5 year life of the hammer.) Now many are made to meet a retail price point and do NOT carry the lifetime guarantee. Thankfully, you can pretty reliably use this test to figure out if any given Craftsman tool is a good one.