Anthropic released Claude Opus 4.5, calling it the best model in the world for coding, agents, and computer use, with gains in reasoning, vision, and mathematics. The company said it scored higher than any human candidate ever on its internal engineering exam within a two-hour limit, led frontier models on SWE-bench Verified, and beat competitors in seven of eight programming languages. Pricing dropped sharply to $5 and $25 per million input and output tokens, bringing top-tier capability closer to everyday use. The API gained an effort parameter for trading speed against capability; Claude Code came to the desktop with an improved Plan Mode; Claude for Chrome reached all Max users; and the Claude for Excel beta widened. Anthropic described it as its most robustly aligned model to date, including stronger resistance to prompt injection.