You're right, but actually running the code can be destructive (even when run as intended). You really need to be careful about dev environments. Even the destructive operations will cost you time (and money) in resetting the dev environment.
Agreed and I think this highlights the importance of interactivity/snappiness as well as idempotency. This is needed for a human to play around with also.
If the agent has fast+safe feeback loop to experiment then it can go through more cycles, faster, and improve its output.
