arXiv:2610.28667v1 Announce Type: new Abstract: Coding agents can now implement a specification, write and run tests, repair failures, and declare the result ready for release. When the same agentic system produces both the software and the evidence of its correctness, a passing test suite is no longer independent evidence: visible tests become an optimization target, code and tests may share one misinterpretation of the specification, and the builder's own tests may simply be incomplete. This paper argues that agent-produced software requires an assurance plane that is structurally independent of the build plane. We characterize four gaps between stakeholder intent and production (requirement, conformance, evaluation, and model gaps) and identify which of them verification can close. We propose a framework that separates building from verifying, introduces a Verification Contract stating what must be demonstrated before release, and organizes verification in a specification-first phase without access to the implementation and an implementation-aware phase based on mutation analysis, property-based testing, and fuzzing, with an assurance report that leaves the release decision to a human. We evaluate the framework in a pre-registered study on three stateful services, two of them written by third-party models, and an EvalPlus pilot. The builder's programs were correct, but its own tests missed subtle interactions: a verifier in a fresh context detected more of the 46 seeded faults than the builder's tests (Holm-corrected p = 0.006) and surfaced the ambiguities of the specification, at the price of rare false oracles. A verifier from another provider did not add detection.