Agile Dev (according to me) means you are trying to specify what the customer want as you develop your code and not specify it right in the beginning.
You can make changes to the specs when you are figuring things out. Also, you do verification when you are somewhat confident in your code is doing what the customer wants, so verification should come towards the end of your development phase (or at least end of developing parts of your code base).
Agile Dev (according to me) means you are trying to specify what the customer want as you develop your code and not specify it right in the beginning.
You can make changes to the specs when you are figuring things out. Also, you do verification when you are somewhat confident in your code is doing what the customer wants, so verification should come towards the end of your development phase (or at least end of developing parts of your code base).