Use list_generators to list available generators when available, otherwise mix help. If you have to run generator tasks, pass --yes. Always prefer to use generators as a basis for code generation, and then modify afterwards.
Use code interfaces on domains to define the contract for calling into Ash resources. See the Code interface guide for more.
After creating or modifying Ash code, run mix ash.codegen <short_name_describing_changes> to ensure any required additional changes are made (like migrations are generated).