No need to overthink it. In any semi-modern language you can (de)serialize anything to and from JSON, so it's really not that hard. The only thing you need to do is have a representation for the plan in your program. Which I will argue is probably the least error-prone way to implement --dry-run anyway (as opposed to sprinkling branches everywhere).

> you can (de)serialize anything to and from JSON, so it's really not that hard

First, it is hard, especially in at least somewhat portable manner.

Second, serialization only matters if you cannot (storage, IPC) pass data around in-memory anyway. That's not the problem raised, though. Whatever the backing implementation, the plan, ultimately, consists of some instructions (verbs in parent) over objects (arguments in parent). Serializing instructions any other way than dropping non-portable named references requires one to define execution language, which is not an easy feat.

> The only thing you need to do is have a representation for the plan in your program.

That "only" is doing lifting heavier than you probably realize. Such representation, which is by the way specified to be executable bidirectionally (roll back capabilities), is a full blown program, so you end up implementing language spec, godegen and execution engines. In cases of relatively simple business models that is going to be the majority of the engineering effort.

Right, but you still have to define every ”verb” your plan will have, their ”arguments”, etc. Not need to write a parser (even Java can serialize/deserialize stuff), as you say, but you have to meta-engineer the tool. Not just script a series of commands.