Why does my AI-written smart contract ship with no properties for a verifier to check?

Formal verification of smart contracts requires invariants and pre/post conditions describing what the code is supposed to do. AI agents write Solidity fluently but produce no property specifications alongside the code; auditors still write those specs by hand, when they write them at all. PropertyGPT, which won the Distinguished Paper Award at NDSS 2025, was the most serious attempt to generate specs automatically from code using LLMs. It reached only 80% recall against expert-written properties, leaving critical invariants missing and contracts going to mainnet without a complete specification. No production development toolchain generates property specifications as a standard step, which means formal verifiers like the Certora Prover are rarely applied even when the code itself is AI-generated.