Claude Opus 5.5

Claude Mastery

Brain vs. Hands: How Anthropic Engineers Claude to Act Safely in the Real World
ByTejinder Singh October 27, 2026

Reading Time: 6 minutesAnthropic engineers Katelyn Lesse and Angela Jiang explained on the Latent Space podcast how Claude separates its reasoning layer from its execution layer — a design called the brain-hands architecture — to keep agentic AI safe at scale. The episode also covers Claude Opus 5.5, the Messages API rebuild in Rust, managed agents as an emerging capability, and how safety classifiers sit between training and production.

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Claude Mastery

How Anthropic Builds Claude With Claude: The Brain-and-Hands Architecture Explained
ByTejinder Singh October 27, 2026

Reading Time: 6 minutesLatent Space’s deep-dive with Anthropic’s engineering and product heads reveals the brain-and-hands architecture behind Claude’s Managed Agents, explaining why separating session state from code execution improves both reliability and security. The episode also contextualises Anthropic’s dramatic efficiency gains and is honest about what remains on the roadmap versus what is already shipped.

Read More How Anthropic Builds Claude With Claude: The Brain-and-Hands Architecture Explained
Claude Mastery

Claude Opus 5.5 Built a Full Game in One Prompt — What That Tells You About Modern AI Capability
ByTejinder Singh October 15, 2026

Reading Time: 4 minutesSimon Willison prompted Claude Opus 5.5 Max through the standard iPhone chat app to build a Three.js game in one shot, and the model spent over three hours producing a working spot-the-difference game with music and achievements. This documents a meaningful shift in who can build interactive digital products — and what plain-language prompting can now accomplish without any coding knowledge.

Read More Claude Opus 5.5 Built a Full Game in One Prompt — What That Tells You About Modern AI Capability
Claude Mastery

Claude Opus 5.5 Composed Retro Game Music From a Single Prompt — Here Is What That Means
ByTejinder Singh October 6, 2026

Reading Time: 4 minutesSimon Willison’s Scrimshaw Jukebox experiment shows Claude Opus 5.5 designing its own music notation format, building a browser-based player for it, and composing retro-style game music — all from one prompt. The capability is real but unverified at scale, and key limitations around audio export, format portability, and model-tier access mean non-technical users should approach it as a promising prototype, not a finished workflow.

Read More Claude Opus 5.5 Composed Retro Game Music From a Single Prompt — Here Is What That Means
Claude Mastery

42 Commits, One Prompt: What Claude Opus 5.5 Did to a Forgotten Python Project
ByTejinder Singh October 5, 2026

Reading Time: 4 minutesSimon Willison handed his dormant Python WebAssembly engine to Claude Opus 5.5 with a single high-level prompt, resulting in 42 commits that brought the project close to full WASM specification compliance. The experiment illustrates how current AI models can extend AI-generated codebases from just months ago — with honest caveats about trust, oversight, and alpha-stage reliability.

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