This was the week of Claude Opus 4.7.
Introducing Claude Opus 4.6
Claude Opus 5: The System Card
Claude Opus 5 is trying to be the best of both worlds.
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.
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.
Introducing Claude Opus 5.5
Claude Opus 5.5 leads in agentic coding and knowledge work, and costs 40% less to run than Opus 5 on typical workloads.
Introducing Claude 4
Discover Claude 4's breakthrough AI capabilities. Experience more reliable, interpretable assistance for complex tasks across work and learning.
AI #176 Part 1: Doing It Live
Enough things added up that this week is getting split into two parts.
Felix Rieseberg on Twitter / X
I remade my homepage with Opus 5.5 and pushed it hard. We made music & movies, drew textures, modeled things in Blender: https://t.co/WOGPQVm6FqI'm really happy with the result! pic.twitter.com/y6yUXaKb7K— Felix Rieseberg (@felixrieseberg) September 27, 2026
AI #158: The Department of War
This was the worst week I have had in quite a while, maybe ever.
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.
Looks not too impressive in this graphics. This is ~ on par with Opus 4.7, apparently. Opus 4.7 was >20x the cost. Full comparison: artificialanalysis.ai/models/comparisons/mimo-v2-5-… (Stated facts *not* independently verified by me! I'm not even sure I am reading that page right)
mr. TIM
Korean lab, Motif, releases a 341B model that performs on par with DSv4 (1.6T) they have some actual architectural innovations and a detailed tech report huggingface.co/Motif-Technologies/Motif-3-Be…
Claude Opus 5.5 anthropic.com/claude-opus-5-5
