A while back I built a small tool called SDKProof. it checks how well an AI coding agent writes an SDK's current API — the stuff that changed in the last major, that the model tends to get wrong because it learned the old version. Claude Opus 5 came out today.
Source: [Dev.to](https://dev.to/kalpitrathore/claude-opus-5-closed-last-years-sdk-gaps-not-this-years-31k3)