Claude Haiku 5.5 (High) by @AnthropicAI has landed in the Agent Arena! Across +20.5K real-world agentic sessions from our global community of users, this release scored +1.48% net improvement and landed at #27 overall.
Its strongest Agent Arena category is Code, where it ranks #15 with +4.83% net improvement.
Haiku 5.5 shows cost efficiency with a median cost per task of $0.09, placing it just outside the Agent Arena Pareto frontier. Nearby on the Pareto frontier, GPT-6 Luna (Max) delivers +3.19% at $0.08/task.
Compared to GPT-5.4 (High) priced at $0.63/task in the #26 spot, Haiku 5.5 costs 86% less. Although Haiku 5.5's net improvement score is lower than other Anthropic models, this model is 97–99% cheaper per task than Claude Sonnet 5.5 (Max), Fable 5.1 (Max), and Opus 5.5 (Max).
Congrats again to the @AnthropicAI team on this release!