Anthropic Launches Claude Sonnet 5 With Near-Opus Performance and 60% Lower API Pricing

As competition in generative artificial intelligence intensifies, the technology rivalry between unicorn startup Anthropic and OpenAI has become a focal point for the tech industry. Each upgrade to Anthropic’s flagship Claude series directly shapes the global cloud-computing ecosystem and the development of enterprise AI applications. It also serves as a key gauge of the future computing costs of commercializing AI.

Anthropic is reportedly preparing to unveil its new flagship model, Claude Opus 5, as early as mid-July 2026. The model is expected to offer lower costs while delivering performance close to Fable 5. A mysterious model code-named Honeycomb previously appeared briefly in the Cursor editor, where testing showed a context limit of 1 million tokens, positioning it to compete directly with OpenAI’s GPT-5.6.

Generative AI applications often face a trade-off between model capability and inference costs. The high-end Claude Opus is suited to complex judgments, but using it throughout a task is more expensive. Anthropic’s new “Advisor strategy” assigns tasks to Sonnet or Haiku and consults Opus only for critical decisions, concentrating advanced reasoning resources where they are needed.

On April 9, 2026, Anthropic launched the advisor tool in beta on the Claude Platform. Developers can configure Opus 4.6 to guide Sonnet 4.6 within a single Messages API request. Company tests showed a 2.7-percentage-point improvement on SWE-bench Multilingual and an 11.9% reduction in the cost of each agent task, or roughly 12%.