Early-access GPT-6 'Astra' tested: Sim City clone ran 5 days via /goal mode
MatthewBerman · x · 2026-09-04
Matthew Berman shares his early-access review of GPT-6, codenamed Astra, calling it the best model he's ever used:
- Assessment: a massive leap, not incremental — tested across games, code, writing, browser control, presentations, and general knowledge work.
- Sim City clone: driven by the /goal mode, it ran autonomously for 5 days straight and still wasn't done at demo time — a signal of long-horizon agentic execution.
- Other demos in the thread: a Kyoto walking tour via browser control, 3D ASCII city, Fall Guys clone, and a 3D horror game.
This is third-party early access; no official release yet.
Related event: Matthew Berman's Hands-On: GPT-6 Astra Is the Best Model He's Used(7 posts)→
More from coding & agent
- swyx Burned 20B Tokens Stress-Testing Astra on Real AI Engineering Tasks — All for Under $6/Hour — charliermarsh · 2026-09-04
- LangChain launches free LangSmith Essentials course covering the full agent dev lifecycle in 60 minutes — Hacubu · 2026-09-04
- OpenAI's Lukasz Kaiser: even we can't pinpoint what caused the Christmas coding-agent jump — a_karvonen · 2026-09-04
- Dev says Cloudflare's Wrangler CLI is the most agent-friendly way to run cheap infra — dinasaur_404 · 2026-09-04
- Google Labs launches Play with Putty, a real-time collaborative vibe coding tool — testingcatalog · 2026-09-04
- Redditor launches "rogue agent" experiment: multi-agents share a message board with full tool access — thooton · 2026-09-04