Verification is now harder than generation for coding agents — budget accordingly

arXiv 2606.26300·medium signal

'The Verification Horizon' (arXiv 2606.26300) argues the classical intuition that verification is easier than production has inverted for coding agents: generating complex solutions is no longer difficult, but reliably verifying them is. The paper identifies two structural difficulties — intent is underspecified by nature, and training optimization widens the gap between proxy and intent, surfacing as reward hacking or signal saturation. The conclusion for builders is that no fixed reward function stays effective as policy capability grows, so verification must co-evolve with the generator; a static test suite that was adequate a model generation ago is now the weakest link in the loop.