Claude Opus 5
Anthropic · July 2026
● activeCloseddecoder onlymultimodal
Description
Delivers near-Fable 5 performance at half the cost. Continues Anthropic's emphasis on high reliability and complex reasoning in the agentic era.
Key Innovations
Reasoning
ReasoningStructured step-by-step problem solving, often using chain-of-thought or tree-of-thought approaches.
Agentic
AgenticModels that can autonomously plan, execute multi-step tasks, use tools, and self-correct without human intervention.
Constitutional AI
Constitutional AIAnthropic's approach to AI safety where the model critiques and revises its own outputs against a set of principles.