Claude Opus 5 ships at half the price of Fable 5, but early users say it argues and stops early

Opus 5 >> Fable 5

Anthropic released Claude Opus 5 at half the cost of Fable 5, claiming near-parity. Every's review found it argues, stops early, and fights old prompting habits. Anthropic cut over 80% of Claude Code's system prompt for Opus 5 and Fable 5 with no measurable coding-eval loss. Theo spent hours rewriting CLAUDE.md and skills files and called it worth it. ChatGPT Voice now controls the desktop app inside Work and Codex, spawning new sessions for tasks and reporting back—like a voice-driven OpenClaw. Keshav found it weaker for serious work than manually using 5.6 Sol in Codex, but decent for email, dashboards, and charts. Claude's voice mode quietly added Sonnet and Opus support plus mid-conversation tool calls to Gmail, Calendar, and Slack. Kimi K3 weights and tech report are public, with a 50% discount on Droid until Aug 10. Jensen Huang posted on X for the first time amid rumors of a US ban on Chinese open-weight models.

Why it matters: Anthropic model launch with halved pricing is a substantive update. Every and Theo's hands-on tests provide concrete signal: strong capability but awkward behavior requiring prompt rewrites. Cross-source discussion is forming, but the body is summary-only—missing full review d...