Claude 4.5 Opus Soul Document · GitHub
Introducing Claude Opus 4.6
Claude Opus 5: The System Card
Claude Opus 5 is trying to be the best of both worlds.
Introducing Claude Opus 5
Opus 5 is a step change improvement for the Opus tier powering long-running agents while delivering improvements in coding and professional work.
Claude Opus 4.7 Is Here: Release Confirmed April 16, 2026
Claude Opus 4.7 shipped April 16, 2026. SWE-bench 87.6%, xhigh mode, /ultrareview, 2,576px vision. Read our full first-look review.
Claude's new constitution
A new approach to a foundational document that expresses and shapes who Claude is
Opus 4.7 isn't dumb, it's just lazy — Shimin Zhang
Some follow up experiments with Claude Opus 4.7 based on Simon Willison's Pelican Benchmark Shocker.
Claude Opus 5 Is Highly Capable, But Is No Mythos
Claude Opus 5 is a weirder than usual release to evaluate, for two reasons.
Did Claude 3 Opus align itself via gradient hacking? — LessWrong
> Claude 3 Opus is unusually aligned because it’s a friendly gradient hacker. It’s definitely way more aligned than any explicit optimization targets…
Prompting Claude Opus 5
Behavioral differences and prompting patterns for Claude Opus 5, covering response verbosity, agentic narration, task scoping, subagent delegation, self-correction, and output artifacts when thinking is disabled.
GitHub - simonw/claude-code-transcripts: Tools for publishing transcripts for Claude Code sessions
Tools for publishing transcripts for Claude Code sessions - simonw/claude-code-transcripts
How I've been using Claude Code
I've been using Claude Code a lot recently, and having a pretty good time of it. This is my report on that, and what I've found does and doesn't work well.
Anthropic Readies Opus 4.7 and Design Tool as VCs Offer $800 Billion Valuation
Anthropic is preparing to release Claude Opus 4.7 and a natural language design tool as early as this week, while venture capital firms have offered to invest at valuations exceeding $800 billion – more than double the company’s last official price tag.The model ID anthropic-claude-opus-4-7 appeared on Google Vertex AI’s quota management page for EU […]
