AI & Machine Learning
May 29, 2026Claude Opus 4.8: the effort dial, fast mode and token math
Claude Opus 4.8 arrives at unchanged pricing with an effort control on all plans, a fast mode at a third of the previous fast-inference cost, and a Messages API change that lets system entries sit inside the messages array so mid-task instruction updates no longer invalidate the prompt cache. Worked token math shows cache hit rate remains the biggest cost lever, and a four-question framework matches effort, speed and fan-out to each workload.
Claude Opus 4.8
Anthropic
AI Agents
LLM Pricing
Prompt Caching
Token Economics
Claude Code
Fast Mode
By Technspire Team