25th July 2026
More than any of these eval scores, what is most exciting to me is something else: Opus 5 is our least prompt injectable model yet. It is a bit buried in the system card, but across PI evals and red teaming, Opus 5 is very hard to prompt inject successfully.
— Boris Cherny, here's that System Card section, page 73
Recent articles
- Some thoughts on the Navier–Stokes Millennium Prize Problem - 8th September 2026
- The Pelican comparison grid for Astra is pretty interesting - 4th September 2026
- OpenAI's rogue agents were caught communicating via public wikis - 4th September 2026