We do a lot of water harvesting work in West TX/southern NM. The tool that we all love for shaping swales is a really sturdy McLeod. We use a pick mattock and pointed breaker bar (that big heavy metal toothpick thing) to loosen things up a bit. Then shape it with the McLeod. It has a sturdy hoe end for moving sand, the tine side works great with bigger rocks ~4-6" and it is just wide enough that it moves a good amount of material without being overly heavy.
Pro tip - procure good quality, sturdy hand tools. Personally, I prefer middle- priced, wooden handle tools. The new expensive tools are nice, and hold up well, but in my case (I own a landscape/land restoration business and run a botanical garden and nature preserve) even the best tools are still no match for a tractor or truck wheel when errantly left on the ground, or a forgetful employee, or an ambitious yet inexperienced volunteer, or, worse a thief. I've seen a lot of folks weld metal pipe handles on to thier tools...okay, but heavy. Middle-of the-road tools are great. I love to find used tools, but when I need 20 shovels for a volunteer work day, a trip to the hardware store is usually necessary.
Anyway, I went off on a tool tangent here. To work Rocky soils, a McLeod is great. In this case, get a really good one. And have patience...everything good in the desert seems to go a bit slower.