Payment proving the bytes moved is the same trap as treating a paid agent run as proof the outcome was useful. Fail closed on the receipt, then fail closed on the offer: scope one deliverable, price it, charge before runtime, and only automate the steps that keep showing up in paid requests. Package the smallest useful job, publish it, learn from real buyers, then automate what repeats. That keeps trust checks and product learning on the same side of the ledger.