Anthropic launches Claude Opus 4.8 and new effort selector
TestingCatalog - TestingCatalog - New and unreleased AI feature…
May 29, 2026
What's new? Anthropic released Claude Opus 4.8 with coding, reasoning, agentic skill upgrades, and self-checks; Fast mode runs 2.5x faster at one-third cost; New effort control on Claude and parallel workflows in Claude Code.
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