Claude Opus 5.5 for Product Designers

Anthropic just updated its frontier AI model, Opus. The new model, Opus 5.5, demonstrates even better results than its predecessor, Opus 5.

Opus 5.5 performs at the level of Claude Fable 5.1 on most work and costs 40% less to run than Opus 5.

In this article, I want to test Opus 5.5 in a real product design task (building a user journey for a mobile app) and compare the results it generates with Fable 5.1

What’s new about Opus 5.5

Unlike Opus 5, a milestone AI model for Anthropic, Opus 5.5 is less revolutionary, but it shows a massive jump in agentic capabilities and performance on most complex work.

Opus 5.5 is an agentic-first AI model

Opus 5.5 has much stronger agentic capabilities, and the test I run with it (I share later in this article) proves that. Anthropic positions Opus 5.5 as its strongest Opus model for long-running coding, large codebases, research, computer use, and…