prompting-opus-4-8listed

# Prompting Claude Opus 4.8 > Source: https://platform.claude.com/docs/en/build-with-claude/prompt-engineering/prompting-claude-opus-4-8 > — snapshot 2026-07-03. If this snapshot is >60 days old and you're doing high-stakes prompt work, > re-fetch and reconcile against the live page. Opus 4.8 performs well out of the box on existing Opus 4.7 prompts. The items below are the behaviors that most often need tuning — and the two at the top are the ones that quietly cost time. Source: Anthropic's *Prompting Claude Opus 4.8* guide, tuned to Claude Code / orchestration / PM work. ## ⚠️ Two things that surprise people first 1. **Thinking is OFF unless you ask for it.** Opus 4.8 only thinks when you set `thinking: {type: "adaptive"}`. If you expected visible reasoning / multi-step deliberation and got a flat direct answer, this is why — it's not a capability drop. Triggering is steerable: large/complex system prompts can make it think *more* than you want; if so, add "Thinking adds latency; use it only when it will meaningfully improve answer quality — typically multi-step reasoning. When in doubt, respond directly." Always measure the effect. 2. **The design house-style is cream + serif + terracotta — and it's wrong for half your surfaces.** On open-ended frontend/slide briefs Opus 4.8 defaults to warm cream/off-white (~`#F4F1EA`), serif display type (Georgia/Fraunces/Playfair), italic word-accents, terracotta/amber accent. Reads well for editorial / hospita