agents are usually benchmarked one task at a time, but professional work pays off only if the whole multi-stage package holds. DeliverBench chains 11 expert-reconstructed projects (financial due diligence, legal drafting, drug safety reporting) through 150 subtasks and 2–15 rounds of new materials and client feedback, with agents inheriting their own earlier errors. Across seven model–harness systems the best scores only 65.0/100 on final delivery and passes 50.0% of subtasks at a 90-point threshold — the failures are mostly failures of carrying work forward coherently.